Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 15637 deletions

diff --git a/gnu/llvm/tools/clang/lib/Sema/SemaDeclCXX.cpp b/gnu/llvm/tools/clang/lib/Sema/SemaDeclCXX.cpp
deleted file mode 100644
index 950a63aa451..00000000000
--- a/gnu/llvm/tools/clang/lib/Sema/SemaDeclCXX.cpp
+++ /dev/null
@@ -1,15637 +0,0 @@
-//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-//  This file implements semantic analysis for C++ declarations.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/AST/ASTConsumer.h"
-#include "clang/AST/ASTContext.h"
-#include "clang/AST/ASTLambda.h"
-#include "clang/AST/ASTMutationListener.h"
-#include "clang/AST/CXXInheritance.h"
-#include "clang/AST/CharUnits.h"
-#include "clang/AST/ComparisonCategories.h"
-#include "clang/AST/EvaluatedExprVisitor.h"
-#include "clang/AST/ExprCXX.h"
-#include "clang/AST/RecordLayout.h"
-#include "clang/AST/RecursiveASTVisitor.h"
-#include "clang/AST/StmtVisitor.h"
-#include "clang/AST/TypeLoc.h"
-#include "clang/AST/TypeOrdering.h"
-#include "clang/Basic/PartialDiagnostic.h"
-#include "clang/Basic/TargetInfo.h"
-#include "clang/Lex/LiteralSupport.h"
-#include "clang/Lex/Preprocessor.h"
-#include "clang/Sema/CXXFieldCollector.h"
-#include "clang/Sema/DeclSpec.h"
-#include "clang/Sema/Initialization.h"
-#include "clang/Sema/Lookup.h"
-#include "clang/Sema/ParsedTemplate.h"
-#include "clang/Sema/Scope.h"
-#include "clang/Sema/ScopeInfo.h"
-#include "clang/Sema/SemaInternal.h"
-#include "clang/Sema/Template.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/StringExtras.h"
-#include <map>
-#include <set>
-
-using namespace clang;
-
-//===----------------------------------------------------------------------===//
-// CheckDefaultArgumentVisitor
-//===----------------------------------------------------------------------===//
-
-namespace {
-  /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
-  /// the default argument of a parameter to determine whether it
-  /// contains any ill-formed subexpressions. For example, this will
-  /// diagnose the use of local variables or parameters within the
-  /// default argument expression.
-  class CheckDefaultArgumentVisitor
-    : public StmtVisitor<CheckDefaultArgumentVisitor, bool> {
-    Expr *DefaultArg;
-    Sema *S;
-
-  public:
-    CheckDefaultArgumentVisitor(Expr *defarg, Sema *s)
-      : DefaultArg(defarg), S(s) {}
-
-    bool VisitExpr(Expr *Node);
-    bool VisitDeclRefExpr(DeclRefExpr *DRE);
-    bool VisitCXXThisExpr(CXXThisExpr *ThisE);
-    bool VisitLambdaExpr(LambdaExpr *Lambda);
-    bool VisitPseudoObjectExpr(PseudoObjectExpr *POE);
-  };
-
-  /// VisitExpr - Visit all of the children of this expression.
-  bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
-    bool IsInvalid = false;
-    for (Stmt *SubStmt : Node->children())
-      IsInvalid |= Visit(SubStmt);
-    return IsInvalid;
-  }
-
-  /// VisitDeclRefExpr - Visit a reference to a declaration, to
-  /// determine whether this declaration can be used in the default
-  /// argument expression.
-  bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
-    NamedDecl *Decl = DRE->getDecl();
-    if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
-      // C++ [dcl.fct.default]p9
-      //   Default arguments are evaluated each time the function is
-      //   called. The order of evaluation of function arguments is
-      //   unspecified. Consequently, parameters of a function shall not
-      //   be used in default argument expressions, even if they are not
-      //   evaluated. Parameters of a function declared before a default
-      //   argument expression are in scope and can hide namespace and
-      //   class member names.
-      return S->Diag(DRE->getBeginLoc(),
-                     diag::err_param_default_argument_references_param)
-             << Param->getDeclName() << DefaultArg->getSourceRange();
-    } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) {
-      // C++ [dcl.fct.default]p7
-      //   Local variables shall not be used in default argument
-      //   expressions.
-      if (VDecl->isLocalVarDecl())
-        return S->Diag(DRE->getBeginLoc(),
-                       diag::err_param_default_argument_references_local)
-               << VDecl->getDeclName() << DefaultArg->getSourceRange();
-    }
-
-    return false;
-  }
-
-  /// VisitCXXThisExpr - Visit a C++ "this" expression.
-  bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) {
-    // C++ [dcl.fct.default]p8:
-    //   The keyword this shall not be used in a default argument of a
-    //   member function.
-    return S->Diag(ThisE->getBeginLoc(),
-                   diag::err_param_default_argument_references_this)
-           << ThisE->getSourceRange();
-  }
-
-  bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
-    bool Invalid = false;
-    for (PseudoObjectExpr::semantics_iterator
-           i = POE->semantics_begin(), e = POE->semantics_end(); i != e; ++i) {
-      Expr *E = *i;
-
-      // Look through bindings.
-      if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
-        E = OVE->getSourceExpr();
-        assert(E && "pseudo-object binding without source expression?");
-      }
-
-      Invalid |= Visit(E);
-    }
-    return Invalid;
-  }
-
-  bool CheckDefaultArgumentVisitor::VisitLambdaExpr(LambdaExpr *Lambda) {
-    // C++11 [expr.lambda.prim]p13:
-    //   A lambda-expression appearing in a default argument shall not
-    //   implicitly or explicitly capture any entity.
-    if (Lambda->capture_begin() == Lambda->capture_end())
-      return false;
-
-    return S->Diag(Lambda->getBeginLoc(), diag::err_lambda_capture_default_arg);
-  }
-}
-
-void
-Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
-                                                 const CXXMethodDecl *Method) {
-  // If we have an MSAny spec already, don't bother.
-  if (!Method || ComputedEST == EST_MSAny)
-    return;
-
-  const FunctionProtoType *Proto
-    = Method->getType()->getAs<FunctionProtoType>();
-  Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
-  if (!Proto)
-    return;
-
-  ExceptionSpecificationType EST = Proto->getExceptionSpecType();
-
-  // If we have a throw-all spec at this point, ignore the function.
-  if (ComputedEST == EST_None)
-    return;
-
-  if (EST == EST_None && Method->hasAttr<NoThrowAttr>())
-    EST = EST_BasicNoexcept;
-
-  switch (EST) {
-  case EST_Unparsed:
-  case EST_Uninstantiated:
-  case EST_Unevaluated:
-    llvm_unreachable("should not see unresolved exception specs here");
-
-  // If this function can throw any exceptions, make a note of that.
-  case EST_MSAny:
-  case EST_None:
-    // FIXME: Whichever we see last of MSAny and None determines our result.
-    // We should make a consistent, order-independent choice here.
-    ClearExceptions();
-    ComputedEST = EST;
-    return;
-  case EST_NoexceptFalse:
-    ClearExceptions();
-    ComputedEST = EST_None;
-    return;
-  // FIXME: If the call to this decl is using any of its default arguments, we
-  // need to search them for potentially-throwing calls.
-  // If this function has a basic noexcept, it doesn't affect the outcome.
-  case EST_BasicNoexcept:
-  case EST_NoexceptTrue:
-    return;
-  // If we're still at noexcept(true) and there's a throw() callee,
-  // change to that specification.
-  case EST_DynamicNone:
-    if (ComputedEST == EST_BasicNoexcept)
-      ComputedEST = EST_DynamicNone;
-    return;
-  case EST_DependentNoexcept:
-    llvm_unreachable(
-        "should not generate implicit declarations for dependent cases");
-  case EST_Dynamic:
-    break;
-  }
-  assert(EST == EST_Dynamic && "EST case not considered earlier.");
-  assert(ComputedEST != EST_None &&
-         "Shouldn't collect exceptions when throw-all is guaranteed.");
-  ComputedEST = EST_Dynamic;
-  // Record the exceptions in this function's exception specification.
-  for (const auto &E : Proto->exceptions())
-    if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)).second)
-      Exceptions.push_back(E);
-}
-
-void Sema::ImplicitExceptionSpecification::CalledExpr(Expr *E) {
-  if (!E || ComputedEST == EST_MSAny)
-    return;
-
-  // FIXME:
-  //
-  // C++0x [except.spec]p14:
-  //   [An] implicit exception-specification specifies the type-id T if and
-  // only if T is allowed by the exception-specification of a function directly
-  // invoked by f's implicit definition; f shall allow all exceptions if any
-  // function it directly invokes allows all exceptions, and f shall allow no
-  // exceptions if every function it directly invokes allows no exceptions.
-  //
-  // Note in particular that if an implicit exception-specification is generated
-  // for a function containing a throw-expression, that specification can still
-  // be noexcept(true).
-  //
-  // Note also that 'directly invoked' is not defined in the standard, and there
-  // is no indication that we should only consider potentially-evaluated calls.
-  //
-  // Ultimately we should implement the intent of the standard: the exception
-  // specification should be the set of exceptions which can be thrown by the
-  // implicit definition. For now, we assume that any non-nothrow expression can
-  // throw any exception.
-
-  if (Self->canThrow(E))
-    ComputedEST = EST_None;
-}
-
-bool
-Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
-                              SourceLocation EqualLoc) {
-  if (RequireCompleteType(Param->getLocation(), Param->getType(),
-                          diag::err_typecheck_decl_incomplete_type)) {
-    Param->setInvalidDecl();
-    return true;
-  }
-
-  // C++ [dcl.fct.default]p5
-  //   A default argument expression is implicitly converted (clause
-  //   4) to the parameter type. The default argument expression has
-  //   the same semantic constraints as the initializer expression in
-  //   a declaration of a variable of the parameter type, using the
-  //   copy-initialization semantics (8.5).
-  InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
-                                                                    Param);
-  InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
-                                                           EqualLoc);
-  InitializationSequence InitSeq(*this, Entity, Kind, Arg);
-  ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
-  if (Result.isInvalid())
-    return true;
-  Arg = Result.getAs<Expr>();
-
-  CheckCompletedExpr(Arg, EqualLoc);
-  Arg = MaybeCreateExprWithCleanups(Arg);
-
-  // Okay: add the default argument to the parameter
-  Param->setDefaultArg(Arg);
-
-  // We have already instantiated this parameter; provide each of the
-  // instantiations with the uninstantiated default argument.
-  UnparsedDefaultArgInstantiationsMap::iterator InstPos
-    = UnparsedDefaultArgInstantiations.find(Param);
-  if (InstPos != UnparsedDefaultArgInstantiations.end()) {
-    for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
-      InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
-
-    // We're done tracking this parameter's instantiations.
-    UnparsedDefaultArgInstantiations.erase(InstPos);
-  }
-
-  return false;
-}
-
-/// ActOnParamDefaultArgument - Check whether the default argument
-/// provided for a function parameter is well-formed. If so, attach it
-/// to the parameter declaration.
-void
-Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
-                                Expr *DefaultArg) {
-  if (!param || !DefaultArg)
-    return;
-
-  ParmVarDecl *Param = cast<ParmVarDecl>(param);
-  UnparsedDefaultArgLocs.erase(Param);
-
-  // Default arguments are only permitted in C++
-  if (!getLangOpts().CPlusPlus) {
-    Diag(EqualLoc, diag::err_param_default_argument)
-      << DefaultArg->getSourceRange();
-    Param->setInvalidDecl();
-    return;
-  }
-
-  // Check for unexpanded parameter packs.
-  if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
-    Param->setInvalidDecl();
-    return;
-  }
-
-  // C++11 [dcl.fct.default]p3
-  //   A default argument expression [...] shall not be specified for a
-  //   parameter pack.
-  if (Param->isParameterPack()) {
-    Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
-        << DefaultArg->getSourceRange();
-    return;
-  }
-
-  // Check that the default argument is well-formed
-  CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg, this);
-  if (DefaultArgChecker.Visit(DefaultArg)) {
-    Param->setInvalidDecl();
-    return;
-  }
-
-  SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
-}
-
-/// ActOnParamUnparsedDefaultArgument - We've seen a default
-/// argument for a function parameter, but we can't parse it yet
-/// because we're inside a class definition. Note that this default
-/// argument will be parsed later.
-void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
-                                             SourceLocation EqualLoc,
-                                             SourceLocation ArgLoc) {
-  if (!param)
-    return;
-
-  ParmVarDecl *Param = cast<ParmVarDecl>(param);
-  Param->setUnparsedDefaultArg();
-  UnparsedDefaultArgLocs[Param] = ArgLoc;
-}
-
-/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
-/// the default argument for the parameter param failed.
-void Sema::ActOnParamDefaultArgumentError(Decl *param,
-                                          SourceLocation EqualLoc) {
-  if (!param)
-    return;
-
-  ParmVarDecl *Param = cast<ParmVarDecl>(param);
-  Param->setInvalidDecl();
-  UnparsedDefaultArgLocs.erase(Param);
-  Param->setDefaultArg(new(Context)
-                       OpaqueValueExpr(EqualLoc,
-                                       Param->getType().getNonReferenceType(),
-                                       VK_RValue));
-}
-
-/// CheckExtraCXXDefaultArguments - Check for any extra default
-/// arguments in the declarator, which is not a function declaration
-/// or definition and therefore is not permitted to have default
-/// arguments. This routine should be invoked for every declarator
-/// that is not a function declaration or definition.
-void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
-  // C++ [dcl.fct.default]p3
-  //   A default argument expression shall be specified only in the
-  //   parameter-declaration-clause of a function declaration or in a
-  //   template-parameter (14.1). It shall not be specified for a
-  //   parameter pack. If it is specified in a
-  //   parameter-declaration-clause, it shall not occur within a
-  //   declarator or abstract-declarator of a parameter-declaration.
-  bool MightBeFunction = D.isFunctionDeclarationContext();
-  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
-    DeclaratorChunk &chunk = D.getTypeObject(i);
-    if (chunk.Kind == DeclaratorChunk::Function) {
-      if (MightBeFunction) {
-        // This is a function declaration. It can have default arguments, but
-        // keep looking in case its return type is a function type with default
-        // arguments.
-        MightBeFunction = false;
-        continue;
-      }
-      for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
-           ++argIdx) {
-        ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
-        if (Param->hasUnparsedDefaultArg()) {
-          std::unique_ptr<CachedTokens> Toks =
-              std::move(chunk.Fun.Params[argIdx].DefaultArgTokens);
-          SourceRange SR;
-          if (Toks->size() > 1)
-            SR = SourceRange((*Toks)[1].getLocation(),
-                             Toks->back().getLocation());
-          else
-            SR = UnparsedDefaultArgLocs[Param];
-          Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
-            << SR;
-        } else if (Param->getDefaultArg()) {
-          Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
-            << Param->getDefaultArg()->getSourceRange();
-          Param->setDefaultArg(nullptr);
-        }
-      }
-    } else if (chunk.Kind != DeclaratorChunk::Paren) {
-      MightBeFunction = false;
-    }
-  }
-}
-
-static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
-  for (unsigned NumParams = FD->getNumParams(); NumParams > 0; --NumParams) {
-    const ParmVarDecl *PVD = FD->getParamDecl(NumParams-1);
-    if (!PVD->hasDefaultArg())
-      return false;
-    if (!PVD->hasInheritedDefaultArg())
-      return true;
-  }
-  return false;
-}
-
-/// MergeCXXFunctionDecl - Merge two declarations of the same C++
-/// function, once we already know that they have the same
-/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
-/// error, false otherwise.
-bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
-                                Scope *S) {
-  bool Invalid = false;
-
-  // The declaration context corresponding to the scope is the semantic
-  // parent, unless this is a local function declaration, in which case
-  // it is that surrounding function.
-  DeclContext *ScopeDC = New->isLocalExternDecl()
-                             ? New->getLexicalDeclContext()
-                             : New->getDeclContext();
-
-  // Find the previous declaration for the purpose of default arguments.
-  FunctionDecl *PrevForDefaultArgs = Old;
-  for (/**/; PrevForDefaultArgs;
-       // Don't bother looking back past the latest decl if this is a local
-       // extern declaration; nothing else could work.
-       PrevForDefaultArgs = New->isLocalExternDecl()
-                                ? nullptr
-                                : PrevForDefaultArgs->getPreviousDecl()) {
-    // Ignore hidden declarations.
-    if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
-      continue;
-
-    if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
-        !New->isCXXClassMember()) {
-      // Ignore default arguments of old decl if they are not in
-      // the same scope and this is not an out-of-line definition of
-      // a member function.
-      continue;
-    }
-
-    if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
-      // If only one of these is a local function declaration, then they are
-      // declared in different scopes, even though isDeclInScope may think
-      // they're in the same scope. (If both are local, the scope check is
-      // sufficient, and if neither is local, then they are in the same scope.)
-      continue;
-    }
-
-    // We found the right previous declaration.
-    break;
-  }
-
-  // C++ [dcl.fct.default]p4:
-  //   For non-template functions, default arguments can be added in
-  //   later declarations of a function in the same
-  //   scope. Declarations in different scopes have completely
-  //   distinct sets of default arguments. That is, declarations in
-  //   inner scopes do not acquire default arguments from
-  //   declarations in outer scopes, and vice versa. In a given
-  //   function declaration, all parameters subsequent to a
-  //   parameter with a default argument shall have default
-  //   arguments supplied in this or previous declarations. A
-  //   default argument shall not be redefined by a later
-  //   declaration (not even to the same value).
-  //
-  // C++ [dcl.fct.default]p6:
-  //   Except for member functions of class templates, the default arguments
-  //   in a member function definition that appears outside of the class
-  //   definition are added to the set of default arguments provided by the
-  //   member function declaration in the class definition.
-  for (unsigned p = 0, NumParams = PrevForDefaultArgs
-                                       ? PrevForDefaultArgs->getNumParams()
-                                       : 0;
-       p < NumParams; ++p) {
-    ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
-    ParmVarDecl *NewParam = New->getParamDecl(p);
-
-    bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
-    bool NewParamHasDfl = NewParam->hasDefaultArg();
-
-    if (OldParamHasDfl && NewParamHasDfl) {
-      unsigned DiagDefaultParamID =
-        diag::err_param_default_argument_redefinition;
-
-      // MSVC accepts that default parameters be redefined for member functions
-      // of template class. The new default parameter's value is ignored.
-      Invalid = true;
-      if (getLangOpts().MicrosoftExt) {
-        CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(New);
-        if (MD && MD->getParent()->getDescribedClassTemplate()) {
-          // Merge the old default argument into the new parameter.
-          NewParam->setHasInheritedDefaultArg();
-          if (OldParam->hasUninstantiatedDefaultArg())
-            NewParam->setUninstantiatedDefaultArg(
-                                      OldParam->getUninstantiatedDefaultArg());
-          else
-            NewParam->setDefaultArg(OldParam->getInit());
-          DiagDefaultParamID = diag::ext_param_default_argument_redefinition;
-          Invalid = false;
-        }
-      }
-
-      // FIXME: If we knew where the '=' was, we could easily provide a fix-it
-      // hint here. Alternatively, we could walk the type-source information
-      // for NewParam to find the last source location in the type... but it
-      // isn't worth the effort right now. This is the kind of test case that
-      // is hard to get right:
-      //   int f(int);
-      //   void g(int (*fp)(int) = f);
-      //   void g(int (*fp)(int) = &f);
-      Diag(NewParam->getLocation(), DiagDefaultParamID)
-        << NewParam->getDefaultArgRange();
-
-      // Look for the function declaration where the default argument was
-      // actually written, which may be a declaration prior to Old.
-      for (auto Older = PrevForDefaultArgs;
-           OldParam->hasInheritedDefaultArg(); /**/) {
-        Older = Older->getPreviousDecl();
-        OldParam = Older->getParamDecl(p);
-      }
-
-      Diag(OldParam->getLocation(), diag::note_previous_definition)
-        << OldParam->getDefaultArgRange();
-    } else if (OldParamHasDfl) {
-      // Merge the old default argument into the new parameter unless the new
-      // function is a friend declaration in a template class. In the latter
-      // case the default arguments will be inherited when the friend
-      // declaration will be instantiated.
-      if (New->getFriendObjectKind() == Decl::FOK_None ||
-          !New->getLexicalDeclContext()->isDependentContext()) {
-        // It's important to use getInit() here;  getDefaultArg()
-        // strips off any top-level ExprWithCleanups.
-        NewParam->setHasInheritedDefaultArg();
-        if (OldParam->hasUnparsedDefaultArg())
-          NewParam->setUnparsedDefaultArg();
-        else if (OldParam->hasUninstantiatedDefaultArg())
-          NewParam->setUninstantiatedDefaultArg(
-                                       OldParam->getUninstantiatedDefaultArg());
-        else
-          NewParam->setDefaultArg(OldParam->getInit());
-      }
-    } else if (NewParamHasDfl) {
-      if (New->getDescribedFunctionTemplate()) {
-        // Paragraph 4, quoted above, only applies to non-template functions.
-        Diag(NewParam->getLocation(),
-             diag::err_param_default_argument_template_redecl)
-          << NewParam->getDefaultArgRange();
-        Diag(PrevForDefaultArgs->getLocation(),
-             diag::note_template_prev_declaration)
-            << false;
-      } else if (New->getTemplateSpecializationKind()
-                   != TSK_ImplicitInstantiation &&
-                 New->getTemplateSpecializationKind() != TSK_Undeclared) {
-        // C++ [temp.expr.spec]p21:
-        //   Default function arguments shall not be specified in a declaration
-        //   or a definition for one of the following explicit specializations:
-        //     - the explicit specialization of a function template;
-        //     - the explicit specialization of a member function template;
-        //     - the explicit specialization of a member function of a class
-        //       template where the class template specialization to which the
-        //       member function specialization belongs is implicitly
-        //       instantiated.
-        Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
-          << (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
-          << New->getDeclName()
-          << NewParam->getDefaultArgRange();
-      } else if (New->getDeclContext()->isDependentContext()) {
-        // C++ [dcl.fct.default]p6 (DR217):
-        //   Default arguments for a member function of a class template shall
-        //   be specified on the initial declaration of the member function
-        //   within the class template.
-        //
-        // Reading the tea leaves a bit in DR217 and its reference to DR205
-        // leads me to the conclusion that one cannot add default function
-        // arguments for an out-of-line definition of a member function of a
-        // dependent type.
-        int WhichKind = 2;
-        if (CXXRecordDecl *Record
-              = dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
-          if (Record->getDescribedClassTemplate())
-            WhichKind = 0;
-          else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
-            WhichKind = 1;
-          else
-            WhichKind = 2;
-        }
-
-        Diag(NewParam->getLocation(),
-             diag::err_param_default_argument_member_template_redecl)
-          << WhichKind
-          << NewParam->getDefaultArgRange();
-      }
-    }
-  }
-
-  // DR1344: If a default argument is added outside a class definition and that
-  // default argument makes the function a special member function, the program
-  // is ill-formed. This can only happen for constructors.
-  if (isa<CXXConstructorDecl>(New) &&
-      New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
-    CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
-                     OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
-    if (NewSM != OldSM) {
-      ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
-      assert(NewParam->hasDefaultArg());
-      Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
-        << NewParam->getDefaultArgRange() << NewSM;
-      Diag(Old->getLocation(), diag::note_previous_declaration);
-    }
-  }
-
-  const FunctionDecl *Def;
-  // C++11 [dcl.constexpr]p1: If any declaration of a function or function
-  // template has a constexpr specifier then all its declarations shall
-  // contain the constexpr specifier.
-  if (New->isConstexpr() != Old->isConstexpr()) {
-    Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
-      << New << New->isConstexpr();
-    Diag(Old->getLocation(), diag::note_previous_declaration);
-    Invalid = true;
-  } else if (!Old->getMostRecentDecl()->isInlined() && New->isInlined() &&
-             Old->isDefined(Def) &&
-             // If a friend function is inlined but does not have 'inline'
-             // specifier, it is a definition. Do not report attribute conflict
-             // in this case, redefinition will be diagnosed later.
-             (New->isInlineSpecified() ||
-              New->getFriendObjectKind() == Decl::FOK_None)) {
-    // C++11 [dcl.fcn.spec]p4:
-    //   If the definition of a function appears in a translation unit before its
-    //   first declaration as inline, the program is ill-formed.
-    Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
-    Diag(Def->getLocation(), diag::note_previous_definition);
-    Invalid = true;
-  }
-
-  // FIXME: It's not clear what should happen if multiple declarations of a
-  // deduction guide have different explicitness. For now at least we simply
-  // reject any case where the explicitness changes.
-  auto *NewGuide = dyn_cast<CXXDeductionGuideDecl>(New);
-  if (NewGuide && NewGuide->isExplicitSpecified() !=
-                      cast<CXXDeductionGuideDecl>(Old)->isExplicitSpecified()) {
-    Diag(New->getLocation(), diag::err_deduction_guide_explicit_mismatch)
-      << NewGuide->isExplicitSpecified();
-    Diag(Old->getLocation(), diag::note_previous_declaration);
-  }
-
-  // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
-  // argument expression, that declaration shall be a definition and shall be
-  // the only declaration of the function or function template in the
-  // translation unit.
-  if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
-      functionDeclHasDefaultArgument(Old)) {
-    Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
-    Diag(Old->getLocation(), diag::note_previous_declaration);
-    Invalid = true;
-  }
-
-  return Invalid;
-}
-
-NamedDecl *
-Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
-                                   MultiTemplateParamsArg TemplateParamLists) {
-  assert(D.isDecompositionDeclarator());
-  const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
-
-  // The syntax only allows a decomposition declarator as a simple-declaration,
-  // a for-range-declaration, or a condition in Clang, but we parse it in more
-  // cases than that.
-  if (!D.mayHaveDecompositionDeclarator()) {
-    Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
-      << Decomp.getSourceRange();
-    return nullptr;
-  }
-
-  if (!TemplateParamLists.empty()) {
-    // FIXME: There's no rule against this, but there are also no rules that
-    // would actually make it usable, so we reject it for now.
-    Diag(TemplateParamLists.front()->getTemplateLoc(),
-         diag::err_decomp_decl_template);
-    return nullptr;
-  }
-
-  Diag(Decomp.getLSquareLoc(),
-       !getLangOpts().CPlusPlus17
-           ? diag::ext_decomp_decl
-           : D.getContext() == DeclaratorContext::ConditionContext
-                 ? diag::ext_decomp_decl_cond
-                 : diag::warn_cxx14_compat_decomp_decl)
-      << Decomp.getSourceRange();
-
-  // The semantic context is always just the current context.
-  DeclContext *const DC = CurContext;
-
-  // C++1z [dcl.dcl]/8:
-  //   The decl-specifier-seq shall contain only the type-specifier auto
-  //   and cv-qualifiers.
-  auto &DS = D.getDeclSpec();
-  {
-    SmallVector<StringRef, 8> BadSpecifiers;
-    SmallVector<SourceLocation, 8> BadSpecifierLocs;
-    if (auto SCS = DS.getStorageClassSpec()) {
-      BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
-      BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
-    }
-    if (auto TSCS = DS.getThreadStorageClassSpec()) {
-      BadSpecifiers.push_back(DeclSpec::getSpecifierName(TSCS));
-      BadSpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
-    }
-    if (DS.isConstexprSpecified()) {
-      BadSpecifiers.push_back("constexpr");
-      BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
-    }
-    if (DS.isInlineSpecified()) {
-      BadSpecifiers.push_back("inline");
-      BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
-    }
-    if (!BadSpecifiers.empty()) {
-      auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
-      Err << (int)BadSpecifiers.size()
-          << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
-      // Don't add FixItHints to remove the specifiers; we do still respect
-      // them when building the underlying variable.
-      for (auto Loc : BadSpecifierLocs)
-        Err << SourceRange(Loc, Loc);
-    }
-    // We can't recover from it being declared as a typedef.
-    if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
-      return nullptr;
-  }
-
-  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
-  QualType R = TInfo->getType();
-
-  if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
-                                      UPPC_DeclarationType))
-    D.setInvalidType();
-
-  // The syntax only allows a single ref-qualifier prior to the decomposition
-  // declarator. No other declarator chunks are permitted. Also check the type
-  // specifier here.
-  if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
-      D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
-      (D.getNumTypeObjects() == 1 &&
-       D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
-    Diag(Decomp.getLSquareLoc(),
-         (D.hasGroupingParens() ||
-          (D.getNumTypeObjects() &&
-           D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
-             ? diag::err_decomp_decl_parens
-             : diag::err_decomp_decl_type)
-        << R;
-
-    // In most cases, there's no actual problem with an explicitly-specified
-    // type, but a function type won't work here, and ActOnVariableDeclarator
-    // shouldn't be called for such a type.
-    if (R->isFunctionType())
-      D.setInvalidType();
-  }
-
-  // Build the BindingDecls.
-  SmallVector<BindingDecl*, 8> Bindings;
-
-  // Build the BindingDecls.
-  for (auto &B : D.getDecompositionDeclarator().bindings()) {
-    // Check for name conflicts.
-    DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
-    LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
-                          ForVisibleRedeclaration);
-    LookupName(Previous, S,
-               /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
-
-    // It's not permitted to shadow a template parameter name.
-    if (Previous.isSingleResult() &&
-        Previous.getFoundDecl()->isTemplateParameter()) {
-      DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
-                                      Previous.getFoundDecl());
-      Previous.clear();
-    }
-
-    bool ConsiderLinkage = DC->isFunctionOrMethod() &&
-                           DS.getStorageClassSpec() == DeclSpec::SCS_extern;
-    FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
-                         /*AllowInlineNamespace*/false);
-    if (!Previous.empty()) {
-      auto *Old = Previous.getRepresentativeDecl();
-      Diag(B.NameLoc, diag::err_redefinition) << B.Name;
-      Diag(Old->getLocation(), diag::note_previous_definition);
-    }
-
-    auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
-    PushOnScopeChains(BD, S, true);
-    Bindings.push_back(BD);
-    ParsingInitForAutoVars.insert(BD);
-  }
-
-  // There are no prior lookup results for the variable itself, because it
-  // is unnamed.
-  DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
-                               Decomp.getLSquareLoc());
-  LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
-                        ForVisibleRedeclaration);
-
-  // Build the variable that holds the non-decomposed object.
-  bool AddToScope = true;
-  NamedDecl *New =
-      ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
-                              MultiTemplateParamsArg(), AddToScope, Bindings);
-  if (AddToScope) {
-    S->AddDecl(New);
-    CurContext->addHiddenDecl(New);
-  }
-
-  if (isInOpenMPDeclareTargetContext())
-    checkDeclIsAllowedInOpenMPTarget(nullptr, New);
-
-  return New;
-}
-
-static bool checkSimpleDecomposition(
-    Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
-    QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
-    llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
-  if ((int64_t)Bindings.size() != NumElems) {
-    S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
-        << DecompType << (unsigned)Bindings.size() << NumElems.toString(10)
-        << (NumElems < Bindings.size());
-    return true;
-  }
-
-  unsigned I = 0;
-  for (auto *B : Bindings) {
-    SourceLocation Loc = B->getLocation();
-    ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
-    if (E.isInvalid())
-      return true;
-    E = GetInit(Loc, E.get(), I++);
-    if (E.isInvalid())
-      return true;
-    B->setBinding(ElemType, E.get());
-  }
-
-  return false;
-}
-
-static bool checkArrayLikeDecomposition(Sema &S,
-                                        ArrayRef<BindingDecl *> Bindings,
-                                        ValueDecl *Src, QualType DecompType,
-                                        const llvm::APSInt &NumElems,
-                                        QualType ElemType) {
-  return checkSimpleDecomposition(
-      S, Bindings, Src, DecompType, NumElems, ElemType,
-      [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
-        ExprResult E = S.ActOnIntegerConstant(Loc, I);
-        if (E.isInvalid())
-          return ExprError();
-        return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
-      });
-}
-
-static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
-                                    ValueDecl *Src, QualType DecompType,
-                                    const ConstantArrayType *CAT) {
-  return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
-                                     llvm::APSInt(CAT->getSize()),
-                                     CAT->getElementType());
-}
-
-static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
-                                     ValueDecl *Src, QualType DecompType,
-                                     const VectorType *VT) {
-  return checkArrayLikeDecomposition(
-      S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
-      S.Context.getQualifiedType(VT->getElementType(),
-                                 DecompType.getQualifiers()));
-}
-
-static bool checkComplexDecomposition(Sema &S,
-                                      ArrayRef<BindingDecl *> Bindings,
-                                      ValueDecl *Src, QualType DecompType,
-                                      const ComplexType *CT) {
-  return checkSimpleDecomposition(
-      S, Bindings, Src, DecompType, llvm::APSInt::get(2),
-      S.Context.getQualifiedType(CT->getElementType(),
-                                 DecompType.getQualifiers()),
-      [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
-        return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
-      });
-}
-
-static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
-                                     TemplateArgumentListInfo &Args) {
-  SmallString<128> SS;
-  llvm::raw_svector_ostream OS(SS);
-  bool First = true;
-  for (auto &Arg : Args.arguments()) {
-    if (!First)
-      OS << ", ";
-    Arg.getArgument().print(PrintingPolicy, OS);
-    First = false;
-  }
-  return OS.str();
-}
-
-static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
-                                     SourceLocation Loc, StringRef Trait,
-                                     TemplateArgumentListInfo &Args,
-                                     unsigned DiagID) {
-  auto DiagnoseMissing = [&] {
-    if (DiagID)
-      S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
-                                               Args);
-    return true;
-  };
-
-  // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
-  NamespaceDecl *Std = S.getStdNamespace();
-  if (!Std)
-    return DiagnoseMissing();
-
-  // Look up the trait itself, within namespace std. We can diagnose various
-  // problems with this lookup even if we've been asked to not diagnose a
-  // missing specialization, because this can only fail if the user has been
-  // declaring their own names in namespace std or we don't support the
-  // standard library implementation in use.
-  LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
-                      Loc, Sema::LookupOrdinaryName);
-  if (!S.LookupQualifiedName(Result, Std))
-    return DiagnoseMissing();
-  if (Result.isAmbiguous())
-    return true;
-
-  ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
-  if (!TraitTD) {
-    Result.suppressDiagnostics();
-    NamedDecl *Found = *Result.begin();
-    S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
-    S.Diag(Found->getLocation(), diag::note_declared_at);
-    return true;
-  }
-
-  // Build the template-id.
-  QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
-  if (TraitTy.isNull())
-    return true;
-  if (!S.isCompleteType(Loc, TraitTy)) {
-    if (DiagID)
-      S.RequireCompleteType(
-          Loc, TraitTy, DiagID,
-          printTemplateArgs(S.Context.getPrintingPolicy(), Args));
-    return true;
-  }
-
-  CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
-  assert(RD && "specialization of class template is not a class?");
-
-  // Look up the member of the trait type.
-  S.LookupQualifiedName(TraitMemberLookup, RD);
-  return TraitMemberLookup.isAmbiguous();
-}
-
-static TemplateArgumentLoc
-getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
-                                   uint64_t I) {
-  TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
-  return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
-}
-
-static TemplateArgumentLoc
-getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
-  return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
-}
-
-namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
-
-static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
-                               llvm::APSInt &Size) {
-  EnterExpressionEvaluationContext ContextRAII(
-      S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
-
-  DeclarationName Value = S.PP.getIdentifierInfo("value");
-  LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
-
-  // Form template argument list for tuple_size<T>.
-  TemplateArgumentListInfo Args(Loc, Loc);
-  Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
-
-  // If there's no tuple_size specialization, it's not tuple-like.
-  if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/0))
-    return IsTupleLike::NotTupleLike;
-
-  // If we get this far, we've committed to the tuple interpretation, but
-  // we can still fail if there actually isn't a usable ::value.
-
-  struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
-    LookupResult &R;
-    TemplateArgumentListInfo &Args;
-    ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
-        : R(R), Args(Args) {}
-    void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
-      S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
-          << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
-    }
-  } Diagnoser(R, Args);
-
-  if (R.empty()) {
-    Diagnoser.diagnoseNotICE(S, Loc, SourceRange());
-    return IsTupleLike::Error;
-  }
-
-  ExprResult E =
-      S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
-  if (E.isInvalid())
-    return IsTupleLike::Error;
-
-  E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser, false);
-  if (E.isInvalid())
-    return IsTupleLike::Error;
-
-  return IsTupleLike::TupleLike;
-}
-
-/// \return std::tuple_element<I, T>::type.
-static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
-                                        unsigned I, QualType T) {
-  // Form template argument list for tuple_element<I, T>.
-  TemplateArgumentListInfo Args(Loc, Loc);
-  Args.addArgument(
-      getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
-  Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
-
-  DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
-  LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
-  if (lookupStdTypeTraitMember(
-          S, R, Loc, "tuple_element", Args,
-          diag::err_decomp_decl_std_tuple_element_not_specialized))
-    return QualType();
-
-  auto *TD = R.getAsSingle<TypeDecl>();
-  if (!TD) {
-    R.suppressDiagnostics();
-    S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
-      << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
-    if (!R.empty())
-      S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
-    return QualType();
-  }
-
-  return S.Context.getTypeDeclType(TD);
-}
-
-namespace {
-struct BindingDiagnosticTrap {
-  Sema &S;
-  DiagnosticErrorTrap Trap;
-  BindingDecl *BD;
-
-  BindingDiagnosticTrap(Sema &S, BindingDecl *BD)
-      : S(S), Trap(S.Diags), BD(BD) {}
-  ~BindingDiagnosticTrap() {
-    if (Trap.hasErrorOccurred())
-      S.Diag(BD->getLocation(), diag::note_in_binding_decl_init) << BD;
-  }
-};
-}
-
-static bool checkTupleLikeDecomposition(Sema &S,
-                                        ArrayRef<BindingDecl *> Bindings,
-                                        VarDecl *Src, QualType DecompType,
-                                        const llvm::APSInt &TupleSize) {
-  if ((int64_t)Bindings.size() != TupleSize) {
-    S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
-        << DecompType << (unsigned)Bindings.size() << TupleSize.toString(10)
-        << (TupleSize < Bindings.size());
-    return true;
-  }
-
-  if (Bindings.empty())
-    return false;
-
-  DeclarationName GetDN = S.PP.getIdentifierInfo("get");
-
-  // [dcl.decomp]p3:
-  //   The unqualified-id get is looked up in the scope of E by class member
-  //   access lookup ...
-  LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
-  bool UseMemberGet = false;
-  if (S.isCompleteType(Src->getLocation(), DecompType)) {
-    if (auto *RD = DecompType->getAsCXXRecordDecl())
-      S.LookupQualifiedName(MemberGet, RD);
-    if (MemberGet.isAmbiguous())
-      return true;
-    //   ... and if that finds at least one declaration that is a function
-    //   template whose first template parameter is a non-type parameter ...
-    for (NamedDecl *D : MemberGet) {
-      if (FunctionTemplateDecl *FTD =
-              dyn_cast<FunctionTemplateDecl>(D->getUnderlyingDecl())) {
-        TemplateParameterList *TPL = FTD->getTemplateParameters();
-        if (TPL->size() != 0 &&
-            isa<NonTypeTemplateParmDecl>(TPL->getParam(0))) {
-          //   ... the initializer is e.get<i>().
-          UseMemberGet = true;
-          break;
-        }
-      }
-    }
-    S.FilterAcceptableTemplateNames(MemberGet);
-  }
-
-  unsigned I = 0;
-  for (auto *B : Bindings) {
-    BindingDiagnosticTrap Trap(S, B);
-    SourceLocation Loc = B->getLocation();
-
-    ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
-    if (E.isInvalid())
-      return true;
-
-    //   e is an lvalue if the type of the entity is an lvalue reference and
-    //   an xvalue otherwise
-    if (!Src->getType()->isLValueReferenceType())
-      E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
-                                   E.get(), nullptr, VK_XValue);
-
-    TemplateArgumentListInfo Args(Loc, Loc);
-    Args.addArgument(
-        getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
-
-    if (UseMemberGet) {
-      //   if [lookup of member get] finds at least one declaration, the
-      //   initializer is e.get<i-1>().
-      E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
-                                     CXXScopeSpec(), SourceLocation(), nullptr,
-                                     MemberGet, &Args, nullptr);
-      if (E.isInvalid())
-        return true;
-
-      E = S.ActOnCallExpr(nullptr, E.get(), Loc, None, Loc);
-    } else {
-      //   Otherwise, the initializer is get<i-1>(e), where get is looked up
-      //   in the associated namespaces.
-      Expr *Get = UnresolvedLookupExpr::Create(
-          S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
-          DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
-          UnresolvedSetIterator(), UnresolvedSetIterator());
-
-      Expr *Arg = E.get();
-      E = S.ActOnCallExpr(nullptr, Get, Loc, Arg, Loc);
-    }
-    if (E.isInvalid())
-      return true;
-    Expr *Init = E.get();
-
-    //   Given the type T designated by std::tuple_element<i - 1, E>::type,
-    QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
-    if (T.isNull())
-      return true;
-
-    //   each vi is a variable of type "reference to T" initialized with the
-    //   initializer, where the reference is an lvalue reference if the
-    //   initializer is an lvalue and an rvalue reference otherwise
-    QualType RefType =
-        S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
-    if (RefType.isNull())
-      return true;
-    auto *RefVD = VarDecl::Create(
-        S.Context, Src->getDeclContext(), Loc, Loc,
-        B->getDeclName().getAsIdentifierInfo(), RefType,
-        S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
-    RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
-    RefVD->setTSCSpec(Src->getTSCSpec());
-    RefVD->setImplicit();
-    if (Src->isInlineSpecified())
-      RefVD->setInlineSpecified();
-    RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
-
-    InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
-    InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
-    InitializationSequence Seq(S, Entity, Kind, Init);
-    E = Seq.Perform(S, Entity, Kind, Init);
-    if (E.isInvalid())
-      return true;
-    E = S.ActOnFinishFullExpr(E.get(), Loc);
-    if (E.isInvalid())
-      return true;
-    RefVD->setInit(E.get());
-    RefVD->checkInitIsICE();
-
-    E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
-                                   DeclarationNameInfo(B->getDeclName(), Loc),
-                                   RefVD);
-    if (E.isInvalid())
-      return true;
-
-    B->setBinding(T, E.get());
-    I++;
-  }
-
-  return false;
-}
-
-/// Find the base class to decompose in a built-in decomposition of a class type.
-/// This base class search is, unfortunately, not quite like any other that we
-/// perform anywhere else in C++.
-static DeclAccessPair findDecomposableBaseClass(Sema &S, SourceLocation Loc,
-                                                const CXXRecordDecl *RD,
-                                                CXXCastPath &BasePath) {
-  auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
-                          CXXBasePath &Path) {
-    return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
-  };
-
-  const CXXRecordDecl *ClassWithFields = nullptr;
-  AccessSpecifier AS = AS_public;
-  if (RD->hasDirectFields())
-    // [dcl.decomp]p4:
-    //   Otherwise, all of E's non-static data members shall be public direct
-    //   members of E ...
-    ClassWithFields = RD;
-  else {
-    //   ... or of ...
-    CXXBasePaths Paths;
-    Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
-    if (!RD->lookupInBases(BaseHasFields, Paths)) {
-      // If no classes have fields, just decompose RD itself. (This will work
-      // if and only if zero bindings were provided.)
-      return DeclAccessPair::make(const_cast<CXXRecordDecl*>(RD), AS_public);
-    }
-
-    CXXBasePath *BestPath = nullptr;
-    for (auto &P : Paths) {
-      if (!BestPath)
-        BestPath = &P;
-      else if (!S.Context.hasSameType(P.back().Base->getType(),
-                                      BestPath->back().Base->getType())) {
-        //   ... the same ...
-        S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
-          << false << RD << BestPath->back().Base->getType()
-          << P.back().Base->getType();
-        return DeclAccessPair();
-      } else if (P.Access < BestPath->Access) {
-        BestPath = &P;
-      }
-    }
-
-    //   ... unambiguous ...
-    QualType BaseType = BestPath->back().Base->getType();
-    if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
-      S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
-        << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
-      return DeclAccessPair();
-    }
-
-    //   ... [accessible, implied by other rules] base class of E.
-    S.CheckBaseClassAccess(Loc, BaseType, S.Context.getRecordType(RD),
-                           *BestPath, diag::err_decomp_decl_inaccessible_base);
-    AS = BestPath->Access;
-
-    ClassWithFields = BaseType->getAsCXXRecordDecl();
-    S.BuildBasePathArray(Paths, BasePath);
-  }
-
-  // The above search did not check whether the selected class itself has base
-  // classes with fields, so check that now.
-  CXXBasePaths Paths;
-  if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
-    S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
-      << (ClassWithFields == RD) << RD << ClassWithFields
-      << Paths.front().back().Base->getType();
-    return DeclAccessPair();
-  }
-
-  return DeclAccessPair::make(const_cast<CXXRecordDecl*>(ClassWithFields), AS);
-}
-
-static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
-                                     ValueDecl *Src, QualType DecompType,
-                                     const CXXRecordDecl *OrigRD) {
-  if (S.RequireCompleteType(Src->getLocation(), DecompType,
-                            diag::err_incomplete_type))
-    return true;
-
-  CXXCastPath BasePath;
-  DeclAccessPair BasePair =
-      findDecomposableBaseClass(S, Src->getLocation(), OrigRD, BasePath);
-  const CXXRecordDecl *RD = cast_or_null<CXXRecordDecl>(BasePair.getDecl());
-  if (!RD)
-    return true;
-  QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
-                                                 DecompType.getQualifiers());
-
-  auto DiagnoseBadNumberOfBindings = [&]() -> bool {
-    unsigned NumFields =
-        std::count_if(RD->field_begin(), RD->field_end(),
-                      [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
-    assert(Bindings.size() != NumFields);
-    S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
-        << DecompType << (unsigned)Bindings.size() << NumFields
-        << (NumFields < Bindings.size());
-    return true;
-  };
-
-  //   all of E's non-static data members shall be [...] well-formed
-  //   when named as e.name in the context of the structured binding,
-  //   E shall not have an anonymous union member, ...
-  unsigned I = 0;
-  for (auto *FD : RD->fields()) {
-    if (FD->isUnnamedBitfield())
-      continue;
-
-    if (FD->isAnonymousStructOrUnion()) {
-      S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
-        << DecompType << FD->getType()->isUnionType();
-      S.Diag(FD->getLocation(), diag::note_declared_at);
-      return true;
-    }
-
-    // We have a real field to bind.
-    if (I >= Bindings.size())
-      return DiagnoseBadNumberOfBindings();
-    auto *B = Bindings[I++];
-    SourceLocation Loc = B->getLocation();
-
-    // The field must be accessible in the context of the structured binding.
-    // We already checked that the base class is accessible.
-    // FIXME: Add 'const' to AccessedEntity's classes so we can remove the
-    // const_cast here.
-    S.CheckStructuredBindingMemberAccess(
-        Loc, const_cast<CXXRecordDecl *>(OrigRD),
-        DeclAccessPair::make(FD, CXXRecordDecl::MergeAccess(
-                                     BasePair.getAccess(), FD->getAccess())));
-
-    // Initialize the binding to Src.FD.
-    ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
-    if (E.isInvalid())
-      return true;
-    E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
-                            VK_LValue, &BasePath);
-    if (E.isInvalid())
-      return true;
-    E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
-                                  CXXScopeSpec(), FD,
-                                  DeclAccessPair::make(FD, FD->getAccess()),
-                                  DeclarationNameInfo(FD->getDeclName(), Loc));
-    if (E.isInvalid())
-      return true;
-
-    // If the type of the member is T, the referenced type is cv T, where cv is
-    // the cv-qualification of the decomposition expression.
-    //
-    // FIXME: We resolve a defect here: if the field is mutable, we do not add
-    // 'const' to the type of the field.
-    Qualifiers Q = DecompType.getQualifiers();
-    if (FD->isMutable())
-      Q.removeConst();
-    B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
-  }
-
-  if (I != Bindings.size())
-    return DiagnoseBadNumberOfBindings();
-
-  return false;
-}
-
-void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
-  QualType DecompType = DD->getType();
-
-  // If the type of the decomposition is dependent, then so is the type of
-  // each binding.
-  if (DecompType->isDependentType()) {
-    for (auto *B : DD->bindings())
-      B->setType(Context.DependentTy);
-    return;
-  }
-
-  DecompType = DecompType.getNonReferenceType();
-  ArrayRef<BindingDecl*> Bindings = DD->bindings();
-
-  // C++1z [dcl.decomp]/2:
-  //   If E is an array type [...]
-  // As an extension, we also support decomposition of built-in complex and
-  // vector types.
-  if (auto *CAT = Context.getAsConstantArrayType(DecompType)) {
-    if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
-      DD->setInvalidDecl();
-    return;
-  }
-  if (auto *VT = DecompType->getAs<VectorType>()) {
-    if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
-      DD->setInvalidDecl();
-    return;
-  }
-  if (auto *CT = DecompType->getAs<ComplexType>()) {
-    if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
-      DD->setInvalidDecl();
-    return;
-  }
-
-  // C++1z [dcl.decomp]/3:
-  //   if the expression std::tuple_size<E>::value is a well-formed integral
-  //   constant expression, [...]
-  llvm::APSInt TupleSize(32);
-  switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
-  case IsTupleLike::Error:
-    DD->setInvalidDecl();
-    return;
-
-  case IsTupleLike::TupleLike:
-    if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
-      DD->setInvalidDecl();
-    return;
-
-  case IsTupleLike::NotTupleLike:
-    break;
-  }
-
-  // C++1z [dcl.dcl]/8:
-  //   [E shall be of array or non-union class type]
-  CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
-  if (!RD || RD->isUnion()) {
-    Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
-        << DD << !RD << DecompType;
-    DD->setInvalidDecl();
-    return;
-  }
-
-  // C++1z [dcl.decomp]/4:
-  //   all of E's non-static data members shall be [...] direct members of
-  //   E or of the same unambiguous public base class of E, ...
-  if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
-    DD->setInvalidDecl();
-}
-
-/// Merge the exception specifications of two variable declarations.
-///
-/// This is called when there's a redeclaration of a VarDecl. The function
-/// checks if the redeclaration might have an exception specification and
-/// validates compatibility and merges the specs if necessary.
-void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
-  // Shortcut if exceptions are disabled.
-  if (!getLangOpts().CXXExceptions)
-    return;
-
-  assert(Context.hasSameType(New->getType(), Old->getType()) &&
-         "Should only be called if types are otherwise the same.");
-
-  QualType NewType = New->getType();
-  QualType OldType = Old->getType();
-
-  // We're only interested in pointers and references to functions, as well
-  // as pointers to member functions.
-  if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
-    NewType = R->getPointeeType();
-    OldType = OldType->getAs<ReferenceType>()->getPointeeType();
-  } else if (const PointerType *P = NewType->getAs<PointerType>()) {
-    NewType = P->getPointeeType();
-    OldType = OldType->getAs<PointerType>()->getPointeeType();
-  } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
-    NewType = M->getPointeeType();
-    OldType = OldType->getAs<MemberPointerType>()->getPointeeType();
-  }
-
-  if (!NewType->isFunctionProtoType())
-    return;
-
-  // There's lots of special cases for functions. For function pointers, system
-  // libraries are hopefully not as broken so that we don't need these
-  // workarounds.
-  if (CheckEquivalentExceptionSpec(
-        OldType->getAs<FunctionProtoType>(), Old->getLocation(),
-        NewType->getAs<FunctionProtoType>(), New->getLocation())) {
-    New->setInvalidDecl();
-  }
-}
-
-/// CheckCXXDefaultArguments - Verify that the default arguments for a
-/// function declaration are well-formed according to C++
-/// [dcl.fct.default].
-void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
-  unsigned NumParams = FD->getNumParams();
-  unsigned p;
-
-  // Find first parameter with a default argument
-  for (p = 0; p < NumParams; ++p) {
-    ParmVarDecl *Param = FD->getParamDecl(p);
-    if (Param->hasDefaultArg())
-      break;
-  }
-
-  // C++11 [dcl.fct.default]p4:
-  //   In a given function declaration, each parameter subsequent to a parameter
-  //   with a default argument shall have a default argument supplied in this or
-  //   a previous declaration or shall be a function parameter pack. A default
-  //   argument shall not be redefined by a later declaration (not even to the
-  //   same value).
-  unsigned LastMissingDefaultArg = 0;
-  for (; p < NumParams; ++p) {
-    ParmVarDecl *Param = FD->getParamDecl(p);
-    if (!Param->hasDefaultArg() && !Param->isParameterPack()) {
-      if (Param->isInvalidDecl())
-        /* We already complained about this parameter. */;
-      else if (Param->getIdentifier())
-        Diag(Param->getLocation(),
-             diag::err_param_default_argument_missing_name)
-          << Param->getIdentifier();
-      else
-        Diag(Param->getLocation(),
-             diag::err_param_default_argument_missing);
-
-      LastMissingDefaultArg = p;
-    }
-  }
-
-  if (LastMissingDefaultArg > 0) {
-    // Some default arguments were missing. Clear out all of the
-    // default arguments up to (and including) the last missing
-    // default argument, so that we leave the function parameters
-    // in a semantically valid state.
-    for (p = 0; p <= LastMissingDefaultArg; ++p) {
-      ParmVarDecl *Param = FD->getParamDecl(p);
-      if (Param->hasDefaultArg()) {
-        Param->setDefaultArg(nullptr);
-      }
-    }
-  }
-}
-
-// CheckConstexprParameterTypes - Check whether a function's parameter types
-// are all literal types. If so, return true. If not, produce a suitable
-// diagnostic and return false.
-static bool CheckConstexprParameterTypes(Sema &SemaRef,
-                                         const FunctionDecl *FD) {
-  unsigned ArgIndex = 0;
-  const FunctionProtoType *FT = FD->getType()->getAs<FunctionProtoType>();
-  for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
-                                              e = FT->param_type_end();
-       i != e; ++i, ++ArgIndex) {
-    const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
-    SourceLocation ParamLoc = PD->getLocation();
-    if (!(*i)->isDependentType() &&
-        SemaRef.RequireLiteralType(ParamLoc, *i,
-                                   diag::err_constexpr_non_literal_param,
-                                   ArgIndex+1, PD->getSourceRange(),
-                                   isa<CXXConstructorDecl>(FD)))
-      return false;
-  }
-  return true;
-}
-
-/// Get diagnostic %select index for tag kind for
-/// record diagnostic message.
-/// WARNING: Indexes apply to particular diagnostics only!
-///
-/// \returns diagnostic %select index.
-static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
-  switch (Tag) {
-  case TTK_Struct: return 0;
-  case TTK_Interface: return 1;
-  case TTK_Class:  return 2;
-  default: llvm_unreachable("Invalid tag kind for record diagnostic!");
-  }
-}
-
-// CheckConstexprFunctionDecl - Check whether a function declaration satisfies
-// the requirements of a constexpr function definition or a constexpr
-// constructor definition. If so, return true. If not, produce appropriate
-// diagnostics and return false.
-//
-// This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
-bool Sema::CheckConstexprFunctionDecl(const FunctionDecl *NewFD) {
-  const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
-  if (MD && MD->isInstance()) {
-    // C++11 [dcl.constexpr]p4:
-    //  The definition of a constexpr constructor shall satisfy the following
-    //  constraints:
-    //  - the class shall not have any virtual base classes;
-    const CXXRecordDecl *RD = MD->getParent();
-    if (RD->getNumVBases()) {
-      Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
-        << isa<CXXConstructorDecl>(NewFD)
-        << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
-      for (const auto &I : RD->vbases())
-        Diag(I.getBeginLoc(), diag::note_constexpr_virtual_base_here)
-            << I.getSourceRange();
-      return false;
-    }
-  }
-
-  if (!isa<CXXConstructorDecl>(NewFD)) {
-    // C++11 [dcl.constexpr]p3:
-    //  The definition of a constexpr function shall satisfy the following
-    //  constraints:
-    // - it shall not be virtual;
-    const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
-    if (Method && Method->isVirtual()) {
-      Method = Method->getCanonicalDecl();
-      Diag(Method->getLocation(), diag::err_constexpr_virtual);
-
-      // If it's not obvious why this function is virtual, find an overridden
-      // function which uses the 'virtual' keyword.
-      const CXXMethodDecl *WrittenVirtual = Method;
-      while (!WrittenVirtual->isVirtualAsWritten())
-        WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
-      if (WrittenVirtual != Method)
-        Diag(WrittenVirtual->getLocation(),
-             diag::note_overridden_virtual_function);
-      return false;
-    }
-
-    // - its return type shall be a literal type;
-    QualType RT = NewFD->getReturnType();
-    if (!RT->isDependentType() &&
-        RequireLiteralType(NewFD->getLocation(), RT,
-                           diag::err_constexpr_non_literal_return))
-      return false;
-  }
-
-  // - each of its parameter types shall be a literal type;
-  if (!CheckConstexprParameterTypes(*this, NewFD))
-    return false;
-
-  return true;
-}
-
-/// Check the given declaration statement is legal within a constexpr function
-/// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
-///
-/// \return true if the body is OK (maybe only as an extension), false if we
-///         have diagnosed a problem.
-static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
-                                   DeclStmt *DS, SourceLocation &Cxx1yLoc) {
-  // C++11 [dcl.constexpr]p3 and p4:
-  //  The definition of a constexpr function(p3) or constructor(p4) [...] shall
-  //  contain only
-  for (const auto *DclIt : DS->decls()) {
-    switch (DclIt->getKind()) {
-    case Decl::StaticAssert:
-    case Decl::Using:
-    case Decl::UsingShadow:
-    case Decl::UsingDirective:
-    case Decl::UnresolvedUsingTypename:
-    case Decl::UnresolvedUsingValue:
-      //   - static_assert-declarations
-      //   - using-declarations,
-      //   - using-directives,
-      continue;
-
-    case Decl::Typedef:
-    case Decl::TypeAlias: {
-      //   - typedef declarations and alias-declarations that do not define
-      //     classes or enumerations,
-      const auto *TN = cast<TypedefNameDecl>(DclIt);
-      if (TN->getUnderlyingType()->isVariablyModifiedType()) {
-        // Don't allow variably-modified types in constexpr functions.
-        TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
-        SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
-          << TL.getSourceRange() << TL.getType()
-          << isa<CXXConstructorDecl>(Dcl);
-        return false;
-      }
-      continue;
-    }
-
-    case Decl::Enum:
-    case Decl::CXXRecord:
-      // C++1y allows types to be defined, not just declared.
-      if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition())
-        SemaRef.Diag(DS->getBeginLoc(),
-                     SemaRef.getLangOpts().CPlusPlus14
-                         ? diag::warn_cxx11_compat_constexpr_type_definition
-                         : diag::ext_constexpr_type_definition)
-            << isa<CXXConstructorDecl>(Dcl);
-      continue;
-
-    case Decl::EnumConstant:
-    case Decl::IndirectField:
-    case Decl::ParmVar:
-      // These can only appear with other declarations which are banned in
-      // C++11 and permitted in C++1y, so ignore them.
-      continue;
-
-    case Decl::Var:
-    case Decl::Decomposition: {
-      // C++1y [dcl.constexpr]p3 allows anything except:
-      //   a definition of a variable of non-literal type or of static or
-      //   thread storage duration or for which no initialization is performed.
-      const auto *VD = cast<VarDecl>(DclIt);
-      if (VD->isThisDeclarationADefinition()) {
-        if (VD->isStaticLocal()) {
-          SemaRef.Diag(VD->getLocation(),
-                       diag::err_constexpr_local_var_static)
-            << isa<CXXConstructorDecl>(Dcl)
-            << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
-          return false;
-        }
-        if (!VD->getType()->isDependentType() &&
-            SemaRef.RequireLiteralType(
-              VD->getLocation(), VD->getType(),
-              diag::err_constexpr_local_var_non_literal_type,
-              isa<CXXConstructorDecl>(Dcl)))
-          return false;
-        if (!VD->getType()->isDependentType() &&
-            !VD->hasInit() && !VD->isCXXForRangeDecl()) {
-          SemaRef.Diag(VD->getLocation(),
-                       diag::err_constexpr_local_var_no_init)
-            << isa<CXXConstructorDecl>(Dcl);
-          return false;
-        }
-      }
-      SemaRef.Diag(VD->getLocation(),
-                   SemaRef.getLangOpts().CPlusPlus14
-                    ? diag::warn_cxx11_compat_constexpr_local_var
-                    : diag::ext_constexpr_local_var)
-        << isa<CXXConstructorDecl>(Dcl);
-      continue;
-    }
-
-    case Decl::NamespaceAlias:
-    case Decl::Function:
-      // These are disallowed in C++11 and permitted in C++1y. Allow them
-      // everywhere as an extension.
-      if (!Cxx1yLoc.isValid())
-        Cxx1yLoc = DS->getBeginLoc();
-      continue;
-
-    default:
-      SemaRef.Diag(DS->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
-          << isa<CXXConstructorDecl>(Dcl);
-      return false;
-    }
-  }
-
-  return true;
-}
-
-/// Check that the given field is initialized within a constexpr constructor.
-///
-/// \param Dcl The constexpr constructor being checked.
-/// \param Field The field being checked. This may be a member of an anonymous
-///        struct or union nested within the class being checked.
-/// \param Inits All declarations, including anonymous struct/union members and
-///        indirect members, for which any initialization was provided.
-/// \param Diagnosed Set to true if an error is produced.
-static void CheckConstexprCtorInitializer(Sema &SemaRef,
-                                          const FunctionDecl *Dcl,
-                                          FieldDecl *Field,
-                                          llvm::SmallSet<Decl*, 16> &Inits,
-                                          bool &Diagnosed) {
-  if (Field->isInvalidDecl())
-    return;
-
-  if (Field->isUnnamedBitfield())
-    return;
-
-  // Anonymous unions with no variant members and empty anonymous structs do not
-  // need to be explicitly initialized. FIXME: Anonymous structs that contain no
-  // indirect fields don't need initializing.
-  if (Field->isAnonymousStructOrUnion() &&
-      (Field->getType()->isUnionType()
-           ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
-           : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
-    return;
-
-  if (!Inits.count(Field)) {
-    if (!Diagnosed) {
-      SemaRef.Diag(Dcl->getLocation(), diag::err_constexpr_ctor_missing_init);
-      Diagnosed = true;
-    }
-    SemaRef.Diag(Field->getLocation(), diag::note_constexpr_ctor_missing_init);
-  } else if (Field->isAnonymousStructOrUnion()) {
-    const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
-    for (auto *I : RD->fields())
-      // If an anonymous union contains an anonymous struct of which any member
-      // is initialized, all members must be initialized.
-      if (!RD->isUnion() || Inits.count(I))
-        CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed);
-  }
-}
-
-/// Check the provided statement is allowed in a constexpr function
-/// definition.
-static bool
-CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
-                           SmallVectorImpl<SourceLocation> &ReturnStmts,
-                           SourceLocation &Cxx1yLoc, SourceLocation &Cxx2aLoc) {
-  // - its function-body shall be [...] a compound-statement that contains only
-  switch (S->getStmtClass()) {
-  case Stmt::NullStmtClass:
-    //   - null statements,
-    return true;
-
-  case Stmt::DeclStmtClass:
-    //   - static_assert-declarations
-    //   - using-declarations,
-    //   - using-directives,
-    //   - typedef declarations and alias-declarations that do not define
-    //     classes or enumerations,
-    if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc))
-      return false;
-    return true;
-
-  case Stmt::ReturnStmtClass:
-    //   - and exactly one return statement;
-    if (isa<CXXConstructorDecl>(Dcl)) {
-      // C++1y allows return statements in constexpr constructors.
-      if (!Cxx1yLoc.isValid())
-        Cxx1yLoc = S->getBeginLoc();
-      return true;
-    }
-
-    ReturnStmts.push_back(S->getBeginLoc());
-    return true;
-
-  case Stmt::CompoundStmtClass: {
-    // C++1y allows compound-statements.
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-
-    CompoundStmt *CompStmt = cast<CompoundStmt>(S);
-    for (auto *BodyIt : CompStmt->body()) {
-      if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
-                                      Cxx1yLoc, Cxx2aLoc))
-        return false;
-    }
-    return true;
-  }
-
-  case Stmt::AttributedStmtClass:
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-    return true;
-
-  case Stmt::IfStmtClass: {
-    // C++1y allows if-statements.
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-
-    IfStmt *If = cast<IfStmt>(S);
-    if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
-                                    Cxx1yLoc, Cxx2aLoc))
-      return false;
-    if (If->getElse() &&
-        !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
-                                    Cxx1yLoc, Cxx2aLoc))
-      return false;
-    return true;
-  }
-
-  case Stmt::WhileStmtClass:
-  case Stmt::DoStmtClass:
-  case Stmt::ForStmtClass:
-  case Stmt::CXXForRangeStmtClass:
-  case Stmt::ContinueStmtClass:
-    // C++1y allows all of these. We don't allow them as extensions in C++11,
-    // because they don't make sense without variable mutation.
-    if (!SemaRef.getLangOpts().CPlusPlus14)
-      break;
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-    for (Stmt *SubStmt : S->children())
-      if (SubStmt &&
-          !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
-                                      Cxx1yLoc, Cxx2aLoc))
-        return false;
-    return true;
-
-  case Stmt::SwitchStmtClass:
-  case Stmt::CaseStmtClass:
-  case Stmt::DefaultStmtClass:
-  case Stmt::BreakStmtClass:
-    // C++1y allows switch-statements, and since they don't need variable
-    // mutation, we can reasonably allow them in C++11 as an extension.
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-    for (Stmt *SubStmt : S->children())
-      if (SubStmt &&
-          !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
-                                      Cxx1yLoc, Cxx2aLoc))
-        return false;
-    return true;
-
-  case Stmt::CXXTryStmtClass:
-    if (Cxx2aLoc.isInvalid())
-      Cxx2aLoc = S->getBeginLoc();
-    for (Stmt *SubStmt : S->children()) {
-      if (SubStmt &&
-          !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
-                                      Cxx1yLoc, Cxx2aLoc))
-        return false;
-    }
-    return true;
-
-  case Stmt::CXXCatchStmtClass:
-    // Do not bother checking the language mode (already covered by the
-    // try block check).
-    if (!CheckConstexprFunctionStmt(SemaRef, Dcl,
-                                    cast<CXXCatchStmt>(S)->getHandlerBlock(),
-                                    ReturnStmts, Cxx1yLoc, Cxx2aLoc))
-      return false;
-    return true;
-
-  default:
-    if (!isa<Expr>(S))
-      break;
-
-    // C++1y allows expression-statements.
-    if (!Cxx1yLoc.isValid())
-      Cxx1yLoc = S->getBeginLoc();
-    return true;
-  }
-
-  SemaRef.Diag(S->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
-      << isa<CXXConstructorDecl>(Dcl);
-  return false;
-}
-
-/// Check the body for the given constexpr function declaration only contains
-/// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
-///
-/// \return true if the body is OK, false if we have diagnosed a problem.
-bool Sema::CheckConstexprFunctionBody(const FunctionDecl *Dcl, Stmt *Body) {
-  SmallVector<SourceLocation, 4> ReturnStmts;
-
-  if (isa<CXXTryStmt>(Body)) {
-    // C++11 [dcl.constexpr]p3:
-    //  The definition of a constexpr function shall satisfy the following
-    //  constraints: [...]
-    // - its function-body shall be = delete, = default, or a
-    //   compound-statement
-    //
-    // C++11 [dcl.constexpr]p4:
-    //  In the definition of a constexpr constructor, [...]
-    // - its function-body shall not be a function-try-block;
-    //
-    // This restriction is lifted in C++2a, as long as inner statements also
-    // apply the general constexpr rules.
-    Diag(Body->getBeginLoc(),
-         !getLangOpts().CPlusPlus2a
-             ? diag::ext_constexpr_function_try_block_cxx2a
-             : diag::warn_cxx17_compat_constexpr_function_try_block)
-        << isa<CXXConstructorDecl>(Dcl);
-  }
-
-  // - its function-body shall be [...] a compound-statement that contains only
-  //   [... list of cases ...]
-  //
-  // Note that walking the children here is enough to properly check for
-  // CompoundStmt and CXXTryStmt body.
-  SourceLocation Cxx1yLoc, Cxx2aLoc;
-  for (Stmt *SubStmt : Body->children()) {
-    if (SubStmt &&
-        !CheckConstexprFunctionStmt(*this, Dcl, SubStmt, ReturnStmts,
-                                    Cxx1yLoc, Cxx2aLoc))
-      return false;
-  }
-
-  if (Cxx2aLoc.isValid())
-    Diag(Cxx2aLoc,
-         getLangOpts().CPlusPlus2a
-           ? diag::warn_cxx17_compat_constexpr_body_invalid_stmt
-           : diag::ext_constexpr_body_invalid_stmt_cxx2a)
-      << isa<CXXConstructorDecl>(Dcl);
-  if (Cxx1yLoc.isValid())
-    Diag(Cxx1yLoc,
-         getLangOpts().CPlusPlus14
-           ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
-           : diag::ext_constexpr_body_invalid_stmt)
-      << isa<CXXConstructorDecl>(Dcl);
-
-  if (const CXXConstructorDecl *Constructor
-        = dyn_cast<CXXConstructorDecl>(Dcl)) {
-    const CXXRecordDecl *RD = Constructor->getParent();
-    // DR1359:
-    // - every non-variant non-static data member and base class sub-object
-    //   shall be initialized;
-    // DR1460:
-    // - if the class is a union having variant members, exactly one of them
-    //   shall be initialized;
-    if (RD->isUnion()) {
-      if (Constructor->getNumCtorInitializers() == 0 &&
-          RD->hasVariantMembers()) {
-        Diag(Dcl->getLocation(), diag::err_constexpr_union_ctor_no_init);
-        return false;
-      }
-    } else if (!Constructor->isDependentContext() &&
-               !Constructor->isDelegatingConstructor()) {
-      assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases");
-
-      // Skip detailed checking if we have enough initializers, and we would
-      // allow at most one initializer per member.
-      bool AnyAnonStructUnionMembers = false;
-      unsigned Fields = 0;
-      for (CXXRecordDecl::field_iterator I = RD->field_begin(),
-           E = RD->field_end(); I != E; ++I, ++Fields) {
-        if (I->isAnonymousStructOrUnion()) {
-          AnyAnonStructUnionMembers = true;
-          break;
-        }
-      }
-      // DR1460:
-      // - if the class is a union-like class, but is not a union, for each of
-      //   its anonymous union members having variant members, exactly one of
-      //   them shall be initialized;
-      if (AnyAnonStructUnionMembers ||
-          Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
-        // Check initialization of non-static data members. Base classes are
-        // always initialized so do not need to be checked. Dependent bases
-        // might not have initializers in the member initializer list.
-        llvm::SmallSet<Decl*, 16> Inits;
-        for (const auto *I: Constructor->inits()) {
-          if (FieldDecl *FD = I->getMember())
-            Inits.insert(FD);
-          else if (IndirectFieldDecl *ID = I->getIndirectMember())
-            Inits.insert(ID->chain_begin(), ID->chain_end());
-        }
-
-        bool Diagnosed = false;
-        for (auto *I : RD->fields())
-          CheckConstexprCtorInitializer(*this, Dcl, I, Inits, Diagnosed);
-        if (Diagnosed)
-          return false;
-      }
-    }
-  } else {
-    if (ReturnStmts.empty()) {
-      // C++1y doesn't require constexpr functions to contain a 'return'
-      // statement. We still do, unless the return type might be void, because
-      // otherwise if there's no return statement, the function cannot
-      // be used in a core constant expression.
-      bool OK = getLangOpts().CPlusPlus14 &&
-                (Dcl->getReturnType()->isVoidType() ||
-                 Dcl->getReturnType()->isDependentType());
-      Diag(Dcl->getLocation(),
-           OK ? diag::warn_cxx11_compat_constexpr_body_no_return
-              : diag::err_constexpr_body_no_return);
-      if (!OK)
-        return false;
-    } else if (ReturnStmts.size() > 1) {
-      Diag(ReturnStmts.back(),
-           getLangOpts().CPlusPlus14
-             ? diag::warn_cxx11_compat_constexpr_body_multiple_return
-             : diag::ext_constexpr_body_multiple_return);
-      for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
-        Diag(ReturnStmts[I], diag::note_constexpr_body_previous_return);
-    }
-  }
-
-  // C++11 [dcl.constexpr]p5:
-  //   if no function argument values exist such that the function invocation
-  //   substitution would produce a constant expression, the program is
-  //   ill-formed; no diagnostic required.
-  // C++11 [dcl.constexpr]p3:
-  //   - every constructor call and implicit conversion used in initializing the
-  //     return value shall be one of those allowed in a constant expression.
-  // C++11 [dcl.constexpr]p4:
-  //   - every constructor involved in initializing non-static data members and
-  //     base class sub-objects shall be a constexpr constructor.
-  SmallVector<PartialDiagnosticAt, 8> Diags;
-  if (!Expr::isPotentialConstantExpr(Dcl, Diags)) {
-    Diag(Dcl->getLocation(), diag::ext_constexpr_function_never_constant_expr)
-      << isa<CXXConstructorDecl>(Dcl);
-    for (size_t I = 0, N = Diags.size(); I != N; ++I)
-      Diag(Diags[I].first, Diags[I].second);
-    // Don't return false here: we allow this for compatibility in
-    // system headers.
-  }
-
-  return true;
-}
-
-/// Get the class that is directly named by the current context. This is the
-/// class for which an unqualified-id in this scope could name a constructor
-/// or destructor.
-///
-/// If the scope specifier denotes a class, this will be that class.
-/// If the scope specifier is empty, this will be the class whose
-/// member-specification we are currently within. Otherwise, there
-/// is no such class.
-CXXRecordDecl *Sema::getCurrentClass(Scope *, const CXXScopeSpec *SS) {
-  assert(getLangOpts().CPlusPlus && "No class names in C!");
-
-  if (SS && SS->isInvalid())
-    return nullptr;
-
-  if (SS && SS->isNotEmpty()) {
-    DeclContext *DC = computeDeclContext(*SS, true);
-    return dyn_cast_or_null<CXXRecordDecl>(DC);
-  }
-
-  return dyn_cast_or_null<CXXRecordDecl>(CurContext);
-}
-
-/// isCurrentClassName - Determine whether the identifier II is the
-/// name of the class type currently being defined. In the case of
-/// nested classes, this will only return true if II is the name of
-/// the innermost class.
-bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *S,
-                              const CXXScopeSpec *SS) {
-  CXXRecordDecl *CurDecl = getCurrentClass(S, SS);
-  return CurDecl && &II == CurDecl->getIdentifier();
-}
-
-/// Determine whether the identifier II is a typo for the name of
-/// the class type currently being defined. If so, update it to the identifier
-/// that should have been used.
-bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
-  assert(getLangOpts().CPlusPlus && "No class names in C!");
-
-  if (!getLangOpts().SpellChecking)
-    return false;
-
-  CXXRecordDecl *CurDecl;
-  if (SS && SS->isSet() && !SS->isInvalid()) {
-    DeclContext *DC = computeDeclContext(*SS, true);
-    CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
-  } else
-    CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
-
-  if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
-      3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
-          < II->getLength()) {
-    II = CurDecl->getIdentifier();
-    return true;
-  }
-
-  return false;
-}
-
-/// Determine whether the given class is a base class of the given
-/// class, including looking at dependent bases.
-static bool findCircularInheritance(const CXXRecordDecl *Class,
-                                    const CXXRecordDecl *Current) {
-  SmallVector<const CXXRecordDecl*, 8> Queue;
-
-  Class = Class->getCanonicalDecl();
-  while (true) {
-    for (const auto &I : Current->bases()) {
-      CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
-      if (!Base)
-        continue;
-
-      Base = Base->getDefinition();
-      if (!Base)
-        continue;
-
-      if (Base->getCanonicalDecl() == Class)
-        return true;
-
-      Queue.push_back(Base);
-    }
-
-    if (Queue.empty())
-      return false;
-
-    Current = Queue.pop_back_val();
-  }
-
-  return false;
-}
-
-/// Check the validity of a C++ base class specifier.
-///
-/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
-/// and returns NULL otherwise.
-CXXBaseSpecifier *
-Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
-                         SourceRange SpecifierRange,
-                         bool Virtual, AccessSpecifier Access,
-                         TypeSourceInfo *TInfo,
-                         SourceLocation EllipsisLoc) {
-  QualType BaseType = TInfo->getType();
-
-  // C++ [class.union]p1:
-  //   A union shall not have base classes.
-  if (Class->isUnion()) {
-    Diag(Class->getLocation(), diag::err_base_clause_on_union)
-      << SpecifierRange;
-    return nullptr;
-  }
-
-  if (EllipsisLoc.isValid() &&
-      !TInfo->getType()->containsUnexpandedParameterPack()) {
-    Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
-      << TInfo->getTypeLoc().getSourceRange();
-    EllipsisLoc = SourceLocation();
-  }
-
-  SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
-
-  if (BaseType->isDependentType()) {
-    // Make sure that we don't have circular inheritance among our dependent
-    // bases. For non-dependent bases, the check for completeness below handles
-    // this.
-    if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
-      if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
-          ((BaseDecl = BaseDecl->getDefinition()) &&
-           findCircularInheritance(Class, BaseDecl))) {
-        Diag(BaseLoc, diag::err_circular_inheritance)
-          << BaseType << Context.getTypeDeclType(Class);
-
-        if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
-          Diag(BaseDecl->getLocation(), diag::note_previous_decl)
-            << BaseType;
-
-        return nullptr;
-      }
-    }
-
-    return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
-                                          Class->getTagKind() == TTK_Class,
-                                          Access, TInfo, EllipsisLoc);
-  }
-
-  // Base specifiers must be record types.
-  if (!BaseType->isRecordType()) {
-    Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
-    return nullptr;
-  }
-
-  // C++ [class.union]p1:
-  //   A union shall not be used as a base class.
-  if (BaseType->isUnionType()) {
-    Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
-    return nullptr;
-  }
-
-  // For the MS ABI, propagate DLL attributes to base class templates.
-  if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
-    if (Attr *ClassAttr = getDLLAttr(Class)) {
-      if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
-              BaseType->getAsCXXRecordDecl())) {
-        propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
-                                            BaseLoc);
-      }
-    }
-  }
-
-  // C++ [class.derived]p2:
-  //   The class-name in a base-specifier shall not be an incompletely
-  //   defined class.
-  if (RequireCompleteType(BaseLoc, BaseType,
-                          diag::err_incomplete_base_class, SpecifierRange)) {
-    Class->setInvalidDecl();
-    return nullptr;
-  }
-
-  // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
-  RecordDecl *BaseDecl = BaseType->getAs<RecordType>()->getDecl();
-  assert(BaseDecl && "Record type has no declaration");
-  BaseDecl = BaseDecl->getDefinition();
-  assert(BaseDecl && "Base type is not incomplete, but has no definition");
-  CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
-  assert(CXXBaseDecl && "Base type is not a C++ type");
-
-  // Microsoft docs say:
-  // "If a base-class has a code_seg attribute, derived classes must have the
-  // same attribute."
-  const auto *BaseCSA = CXXBaseDecl->getAttr<CodeSegAttr>();
-  const auto *DerivedCSA = Class->getAttr<CodeSegAttr>();
-  if ((DerivedCSA || BaseCSA) &&
-      (!BaseCSA || !DerivedCSA || BaseCSA->getName() != DerivedCSA->getName())) {
-    Diag(Class->getLocation(), diag::err_mismatched_code_seg_base);
-    Diag(CXXBaseDecl->getLocation(), diag::note_base_class_specified_here)
-      << CXXBaseDecl;
-    return nullptr;
-  }
-
-  // A class which contains a flexible array member is not suitable for use as a
-  // base class:
-  //   - If the layout determines that a base comes before another base,
-  //     the flexible array member would index into the subsequent base.
-  //   - If the layout determines that base comes before the derived class,
-  //     the flexible array member would index into the derived class.
-  if (CXXBaseDecl->hasFlexibleArrayMember()) {
-    Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
-      << CXXBaseDecl->getDeclName();
-    return nullptr;
-  }
-
-  // C++ [class]p3:
-  //   If a class is marked final and it appears as a base-type-specifier in
-  //   base-clause, the program is ill-formed.
-  if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
-    Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
-      << CXXBaseDecl->getDeclName()
-      << FA->isSpelledAsSealed();
-    Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
-        << CXXBaseDecl->getDeclName() << FA->getRange();
-    return nullptr;
-  }
-
-  if (BaseDecl->isInvalidDecl())
-    Class->setInvalidDecl();
-
-  // Create the base specifier.
-  return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
-                                        Class->getTagKind() == TTK_Class,
-                                        Access, TInfo, EllipsisLoc);
-}
-
-/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
-/// one entry in the base class list of a class specifier, for
-/// example:
-///    class foo : public bar, virtual private baz {
-/// 'public bar' and 'virtual private baz' are each base-specifiers.
-BaseResult
-Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
-                         ParsedAttributes &Attributes,
-                         bool Virtual, AccessSpecifier Access,
-                         ParsedType basetype, SourceLocation BaseLoc,
-                         SourceLocation EllipsisLoc) {
-  if (!classdecl)
-    return true;
-
-  AdjustDeclIfTemplate(classdecl);
-  CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
-  if (!Class)
-    return true;
-
-  // We haven't yet attached the base specifiers.
-  Class->setIsParsingBaseSpecifiers();
-
-  // We do not support any C++11 attributes on base-specifiers yet.
-  // Diagnose any attributes we see.
-  for (const ParsedAttr &AL : Attributes) {
-    if (AL.isInvalid() || AL.getKind() == ParsedAttr::IgnoredAttribute)
-      continue;
-    Diag(AL.getLoc(), AL.getKind() == ParsedAttr::UnknownAttribute
-                          ? (unsigned)diag::warn_unknown_attribute_ignored
-                          : (unsigned)diag::err_base_specifier_attribute)
-        << AL.getName();
-  }
-
-  TypeSourceInfo *TInfo = nullptr;
-  GetTypeFromParser(basetype, &TInfo);
-
-  if (EllipsisLoc.isInvalid() &&
-      DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
-                                      UPPC_BaseType))
-    return true;
-
-  if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
-                                                      Virtual, Access, TInfo,
-                                                      EllipsisLoc))
-    return BaseSpec;
-  else
-    Class->setInvalidDecl();
-
-  return true;
-}
-
-/// Use small set to collect indirect bases.  As this is only used
-/// locally, there's no need to abstract the small size parameter.
-typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
-
-/// Recursively add the bases of Type.  Don't add Type itself.
-static void
-NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
-                  const QualType &Type)
-{
-  // Even though the incoming type is a base, it might not be
-  // a class -- it could be a template parm, for instance.
-  if (auto Rec = Type->getAs<RecordType>()) {
-    auto Decl = Rec->getAsCXXRecordDecl();
-
-    // Iterate over its bases.
-    for (const auto &BaseSpec : Decl->bases()) {
-      QualType Base = Context.getCanonicalType(BaseSpec.getType())
-        .getUnqualifiedType();
-      if (Set.insert(Base).second)
-        // If we've not already seen it, recurse.
-        NoteIndirectBases(Context, Set, Base);
-    }
-  }
-}
-
-/// Performs the actual work of attaching the given base class
-/// specifiers to a C++ class.
-bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
-                                MutableArrayRef<CXXBaseSpecifier *> Bases) {
- if (Bases.empty())
-    return false;
-
-  // Used to keep track of which base types we have already seen, so
-  // that we can properly diagnose redundant direct base types. Note
-  // that the key is always the unqualified canonical type of the base
-  // class.
-  std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
-
-  // Used to track indirect bases so we can see if a direct base is
-  // ambiguous.
-  IndirectBaseSet IndirectBaseTypes;
-
-  // Copy non-redundant base specifiers into permanent storage.
-  unsigned NumGoodBases = 0;
-  bool Invalid = false;
-  for (unsigned idx = 0; idx < Bases.size(); ++idx) {
-    QualType NewBaseType
-      = Context.getCanonicalType(Bases[idx]->getType());
-    NewBaseType = NewBaseType.getLocalUnqualifiedType();
-
-    CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
-    if (KnownBase) {
-      // C++ [class.mi]p3:
-      //   A class shall not be specified as a direct base class of a
-      //   derived class more than once.
-      Diag(Bases[idx]->getBeginLoc(), diag::err_duplicate_base_class)
-          << KnownBase->getType() << Bases[idx]->getSourceRange();
-
-      // Delete the duplicate base class specifier; we're going to
-      // overwrite its pointer later.
-      Context.Deallocate(Bases[idx]);
-
-      Invalid = true;
-    } else {
-      // Okay, add this new base class.
-      KnownBase = Bases[idx];
-      Bases[NumGoodBases++] = Bases[idx];
-
-      // Note this base's direct & indirect bases, if there could be ambiguity.
-      if (Bases.size() > 1)
-        NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
-
-      if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
-        const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
-        if (Class->isInterface() &&
-              (!RD->isInterfaceLike() ||
-               KnownBase->getAccessSpecifier() != AS_public)) {
-          // The Microsoft extension __interface does not permit bases that
-          // are not themselves public interfaces.
-          Diag(KnownBase->getBeginLoc(), diag::err_invalid_base_in_interface)
-              << getRecordDiagFromTagKind(RD->getTagKind()) << RD
-              << RD->getSourceRange();
-          Invalid = true;
-        }
-        if (RD->hasAttr<WeakAttr>())
-          Class->addAttr(WeakAttr::CreateImplicit(Context));
-      }
-    }
-  }
-
-  // Attach the remaining base class specifiers to the derived class.
-  Class->setBases(Bases.data(), NumGoodBases);
-
-  // Check that the only base classes that are duplicate are virtual.
-  for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
-    // Check whether this direct base is inaccessible due to ambiguity.
-    QualType BaseType = Bases[idx]->getType();
-
-    // Skip all dependent types in templates being used as base specifiers.
-    // Checks below assume that the base specifier is a CXXRecord.
-    if (BaseType->isDependentType())
-      continue;
-
-    CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
-      .getUnqualifiedType();
-
-    if (IndirectBaseTypes.count(CanonicalBase)) {
-      CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
-                         /*DetectVirtual=*/true);
-      bool found
-        = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
-      assert(found);
-      (void)found;
-
-      if (Paths.isAmbiguous(CanonicalBase))
-        Diag(Bases[idx]->getBeginLoc(), diag::warn_inaccessible_base_class)
-            << BaseType << getAmbiguousPathsDisplayString(Paths)
-            << Bases[idx]->getSourceRange();
-      else
-        assert(Bases[idx]->isVirtual());
-    }
-
-    // Delete the base class specifier, since its data has been copied
-    // into the CXXRecordDecl.
-    Context.Deallocate(Bases[idx]);
-  }
-
-  return Invalid;
-}
-
-/// ActOnBaseSpecifiers - Attach the given base specifiers to the
-/// class, after checking whether there are any duplicate base
-/// classes.
-void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
-                               MutableArrayRef<CXXBaseSpecifier *> Bases) {
-  if (!ClassDecl || Bases.empty())
-    return;
-
-  AdjustDeclIfTemplate(ClassDecl);
-  AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
-}
-
-/// Determine whether the type \p Derived is a C++ class that is
-/// derived from the type \p Base.
-bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
-  if (!getLangOpts().CPlusPlus)
-    return false;
-
-  CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
-  if (!DerivedRD)
-    return false;
-
-  CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
-  if (!BaseRD)
-    return false;
-
-  // If either the base or the derived type is invalid, don't try to
-  // check whether one is derived from the other.
-  if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
-    return false;
-
-  // FIXME: In a modules build, do we need the entire path to be visible for us
-  // to be able to use the inheritance relationship?
-  if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
-    return false;
-
-  return DerivedRD->isDerivedFrom(BaseRD);
-}
-
-/// Determine whether the type \p Derived is a C++ class that is
-/// derived from the type \p Base.
-bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
-                         CXXBasePaths &Paths) {
-  if (!getLangOpts().CPlusPlus)
-    return false;
-
-  CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
-  if (!DerivedRD)
-    return false;
-
-  CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
-  if (!BaseRD)
-    return false;
-
-  if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
-    return false;
-
-  return DerivedRD->isDerivedFrom(BaseRD, Paths);
-}
-
-static void BuildBasePathArray(const CXXBasePath &Path,
-                               CXXCastPath &BasePathArray) {
-  // We first go backward and check if we have a virtual base.
-  // FIXME: It would be better if CXXBasePath had the base specifier for
-  // the nearest virtual base.
-  unsigned Start = 0;
-  for (unsigned I = Path.size(); I != 0; --I) {
-    if (Path[I - 1].Base->isVirtual()) {
-      Start = I - 1;
-      break;
-    }
-  }
-
-  // Now add all bases.
-  for (unsigned I = Start, E = Path.size(); I != E; ++I)
-    BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
-}
-
-
-void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
-                              CXXCastPath &BasePathArray) {
-  assert(BasePathArray.empty() && "Base path array must be empty!");
-  assert(Paths.isRecordingPaths() && "Must record paths!");
-  return ::BuildBasePathArray(Paths.front(), BasePathArray);
-}
-/// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
-/// conversion (where Derived and Base are class types) is
-/// well-formed, meaning that the conversion is unambiguous (and
-/// that all of the base classes are accessible). Returns true
-/// and emits a diagnostic if the code is ill-formed, returns false
-/// otherwise. Loc is the location where this routine should point to
-/// if there is an error, and Range is the source range to highlight
-/// if there is an error.
-///
-/// If either InaccessibleBaseID or AmbigiousBaseConvID are 0, then the
-/// diagnostic for the respective type of error will be suppressed, but the
-/// check for ill-formed code will still be performed.
-bool
-Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
-                                   unsigned InaccessibleBaseID,
-                                   unsigned AmbigiousBaseConvID,
-                                   SourceLocation Loc, SourceRange Range,
-                                   DeclarationName Name,
-                                   CXXCastPath *BasePath,
-                                   bool IgnoreAccess) {
-  // First, determine whether the path from Derived to Base is
-  // ambiguous. This is slightly more expensive than checking whether
-  // the Derived to Base conversion exists, because here we need to
-  // explore multiple paths to determine if there is an ambiguity.
-  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
-                     /*DetectVirtual=*/false);
-  bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
-  if (!DerivationOkay)
-    return true;
-
-  const CXXBasePath *Path = nullptr;
-  if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType()))
-    Path = &Paths.front();
-
-  // For MSVC compatibility, check if Derived directly inherits from Base. Clang
-  // warns about this hierarchy under -Winaccessible-base, but MSVC allows the
-  // user to access such bases.
-  if (!Path && getLangOpts().MSVCCompat) {
-    for (const CXXBasePath &PossiblePath : Paths) {
-      if (PossiblePath.size() == 1) {
-        Path = &PossiblePath;
-        if (AmbigiousBaseConvID)
-          Diag(Loc, diag::ext_ms_ambiguous_direct_base)
-              << Base << Derived << Range;
-        break;
-      }
-    }
-  }
-
-  if (Path) {
-    if (!IgnoreAccess) {
-      // Check that the base class can be accessed.
-      switch (
-          CheckBaseClassAccess(Loc, Base, Derived, *Path, InaccessibleBaseID)) {
-      case AR_inaccessible:
-        return true;
-      case AR_accessible:
-      case AR_dependent:
-      case AR_delayed:
-        break;
-      }
-    }
-
-    // Build a base path if necessary.
-    if (BasePath)
-      ::BuildBasePathArray(*Path, *BasePath);
-    return false;
-  }
-
-  if (AmbigiousBaseConvID) {
-    // We know that the derived-to-base conversion is ambiguous, and
-    // we're going to produce a diagnostic. Perform the derived-to-base
-    // search just one more time to compute all of the possible paths so
-    // that we can print them out. This is more expensive than any of
-    // the previous derived-to-base checks we've done, but at this point
-    // performance isn't as much of an issue.
-    Paths.clear();
-    Paths.setRecordingPaths(true);
-    bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
-    assert(StillOkay && "Can only be used with a derived-to-base conversion");
-    (void)StillOkay;
-
-    // Build up a textual representation of the ambiguous paths, e.g.,
-    // D -> B -> A, that will be used to illustrate the ambiguous
-    // conversions in the diagnostic. We only print one of the paths
-    // to each base class subobject.
-    std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
-
-    Diag(Loc, AmbigiousBaseConvID)
-    << Derived << Base << PathDisplayStr << Range << Name;
-  }
-  return true;
-}
-
-bool
-Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
-                                   SourceLocation Loc, SourceRange Range,
-                                   CXXCastPath *BasePath,
-                                   bool IgnoreAccess) {
-  return CheckDerivedToBaseConversion(
-      Derived, Base, diag::err_upcast_to_inaccessible_base,
-      diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
-      BasePath, IgnoreAccess);
-}
-
-
-/// Builds a string representing ambiguous paths from a
-/// specific derived class to different subobjects of the same base
-/// class.
-///
-/// This function builds a string that can be used in error messages
-/// to show the different paths that one can take through the
-/// inheritance hierarchy to go from the derived class to different
-/// subobjects of a base class. The result looks something like this:
-/// @code
-/// struct D -> struct B -> struct A
-/// struct D -> struct C -> struct A
-/// @endcode
-std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
-  std::string PathDisplayStr;
-  std::set<unsigned> DisplayedPaths;
-  for (CXXBasePaths::paths_iterator Path = Paths.begin();
-       Path != Paths.end(); ++Path) {
-    if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
-      // We haven't displayed a path to this particular base
-      // class subobject yet.
-      PathDisplayStr += "\n    ";
-      PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
-      for (CXXBasePath::const_iterator Element = Path->begin();
-           Element != Path->end(); ++Element)
-        PathDisplayStr += " -> " + Element->Base->getType().getAsString();
-    }
-  }
-
-  return PathDisplayStr;
-}
-
-//===----------------------------------------------------------------------===//
-// C++ class member Handling
-//===----------------------------------------------------------------------===//
-
-/// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
-bool Sema::ActOnAccessSpecifier(AccessSpecifier Access, SourceLocation ASLoc,
-                                SourceLocation ColonLoc,
-                                const ParsedAttributesView &Attrs) {
-  assert(Access != AS_none && "Invalid kind for syntactic access specifier!");
-  AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
-                                                  ASLoc, ColonLoc);
-  CurContext->addHiddenDecl(ASDecl);
-  return ProcessAccessDeclAttributeList(ASDecl, Attrs);
-}
-
-/// CheckOverrideControl - Check C++11 override control semantics.
-void Sema::CheckOverrideControl(NamedDecl *D) {
-  if (D->isInvalidDecl())
-    return;
-
-  // We only care about "override" and "final" declarations.
-  if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
-    return;
-
-  CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
-
-  // We can't check dependent instance methods.
-  if (MD && MD->isInstance() &&
-      (MD->getParent()->hasAnyDependentBases() ||
-       MD->getType()->isDependentType()))
-    return;
-
-  if (MD && !MD->isVirtual()) {
-    // If we have a non-virtual method, check if if hides a virtual method.
-    // (In that case, it's most likely the method has the wrong type.)
-    SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
-    FindHiddenVirtualMethods(MD, OverloadedMethods);
-
-    if (!OverloadedMethods.empty()) {
-      if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
-        Diag(OA->getLocation(),
-             diag::override_keyword_hides_virtual_member_function)
-          << "override" << (OverloadedMethods.size() > 1);
-      } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
-        Diag(FA->getLocation(),
-             diag::override_keyword_hides_virtual_member_function)
-          << (FA->isSpelledAsSealed() ? "sealed" : "final")
-          << (OverloadedMethods.size() > 1);
-      }
-      NoteHiddenVirtualMethods(MD, OverloadedMethods);
-      MD->setInvalidDecl();
-      return;
-    }
-    // Fall through into the general case diagnostic.
-    // FIXME: We might want to attempt typo correction here.
-  }
-
-  if (!MD || !MD->isVirtual()) {
-    if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
-      Diag(OA->getLocation(),
-           diag::override_keyword_only_allowed_on_virtual_member_functions)
-        << "override" << FixItHint::CreateRemoval(OA->getLocation());
-      D->dropAttr<OverrideAttr>();
-    }
-    if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
-      Diag(FA->getLocation(),
-           diag::override_keyword_only_allowed_on_virtual_member_functions)
-        << (FA->isSpelledAsSealed() ? "sealed" : "final")
-        << FixItHint::CreateRemoval(FA->getLocation());
-      D->dropAttr<FinalAttr>();
-    }
-    return;
-  }
-
-  // C++11 [class.virtual]p5:
-  //   If a function is marked with the virt-specifier override and
-  //   does not override a member function of a base class, the program is
-  //   ill-formed.
-  bool HasOverriddenMethods = MD->size_overridden_methods() != 0;
-  if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
-    Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
-      << MD->getDeclName();
-}
-
-void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D) {
-  if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
-    return;
-  CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
-  if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>())
-    return;
-
-  SourceLocation Loc = MD->getLocation();
-  SourceLocation SpellingLoc = Loc;
-  if (getSourceManager().isMacroArgExpansion(Loc))
-    SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).getBegin();
-  SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
-  if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
-      return;
-
-  if (MD->size_overridden_methods() > 0) {
-    unsigned DiagID = isa<CXXDestructorDecl>(MD)
-                          ? diag::warn_destructor_marked_not_override_overriding
-                          : diag::warn_function_marked_not_override_overriding;
-    Diag(MD->getLocation(), DiagID) << MD->getDeclName();
-    const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
-    Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
-  }
-}
-
-/// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
-/// function overrides a virtual member function marked 'final', according to
-/// C++11 [class.virtual]p4.
-bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
-                                                  const CXXMethodDecl *Old) {
-  FinalAttr *FA = Old->getAttr<FinalAttr>();
-  if (!FA)
-    return false;
-
-  Diag(New->getLocation(), diag::err_final_function_overridden)
-    << New->getDeclName()
-    << FA->isSpelledAsSealed();
-  Diag(Old->getLocation(), diag::note_overridden_virtual_function);
-  return true;
-}
-
-static bool InitializationHasSideEffects(const FieldDecl &FD) {
-  const Type *T = FD.getType()->getBaseElementTypeUnsafe();
-  // FIXME: Destruction of ObjC lifetime types has side-effects.
-  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
-    return !RD->isCompleteDefinition() ||
-           !RD->hasTrivialDefaultConstructor() ||
-           !RD->hasTrivialDestructor();
-  return false;
-}
-
-static const ParsedAttr *getMSPropertyAttr(const ParsedAttributesView &list) {
-  ParsedAttributesView::const_iterator Itr =
-      llvm::find_if(list, [](const ParsedAttr &AL) {
-        return AL.isDeclspecPropertyAttribute();
-      });
-  if (Itr != list.end())
-    return &*Itr;
-  return nullptr;
-}
-
-// Check if there is a field shadowing.
-void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
-                                      DeclarationName FieldName,
-                                      const CXXRecordDecl *RD,
-                                      bool DeclIsField) {
-  if (Diags.isIgnored(diag::warn_shadow_field, Loc))
-    return;
-
-  // To record a shadowed field in a base
-  std::map<CXXRecordDecl*, NamedDecl*> Bases;
-  auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
-                           CXXBasePath &Path) {
-    const auto Base = Specifier->getType()->getAsCXXRecordDecl();
-    // Record an ambiguous path directly
-    if (Bases.find(Base) != Bases.end())
-      return true;
-    for (const auto Field : Base->lookup(FieldName)) {
-      if ((isa<FieldDecl>(Field) || isa<IndirectFieldDecl>(Field)) &&
-          Field->getAccess() != AS_private) {
-        assert(Field->getAccess() != AS_none);
-        assert(Bases.find(Base) == Bases.end());
-        Bases[Base] = Field;
-        return true;
-      }
-    }
-    return false;
-  };
-
-  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
-                     /*DetectVirtual=*/true);
-  if (!RD->lookupInBases(FieldShadowed, Paths))
-    return;
-
-  for (const auto &P : Paths) {
-    auto Base = P.back().Base->getType()->getAsCXXRecordDecl();
-    auto It = Bases.find(Base);
-    // Skip duplicated bases
-    if (It == Bases.end())
-      continue;
-    auto BaseField = It->second;
-    assert(BaseField->getAccess() != AS_private);
-    if (AS_none !=
-        CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
-      Diag(Loc, diag::warn_shadow_field)
-        << FieldName << RD << Base << DeclIsField;
-      Diag(BaseField->getLocation(), diag::note_shadow_field);
-      Bases.erase(It);
-    }
-  }
-}
-
-/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
-/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
-/// bitfield width if there is one, 'InitExpr' specifies the initializer if
-/// one has been parsed, and 'InitStyle' is set if an in-class initializer is
-/// present (but parsing it has been deferred).
-NamedDecl *
-Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
-                               MultiTemplateParamsArg TemplateParameterLists,
-                               Expr *BW, const VirtSpecifiers &VS,
-                               InClassInitStyle InitStyle) {
-  const DeclSpec &DS = D.getDeclSpec();
-  DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
-  DeclarationName Name = NameInfo.getName();
-  SourceLocation Loc = NameInfo.getLoc();
-
-  // For anonymous bitfields, the location should point to the type.
-  if (Loc.isInvalid())
-    Loc = D.getBeginLoc();
-
-  Expr *BitWidth = static_cast<Expr*>(BW);
-
-  assert(isa<CXXRecordDecl>(CurContext));
-  assert(!DS.isFriendSpecified());
-
-  bool isFunc = D.isDeclarationOfFunction();
-  const ParsedAttr *MSPropertyAttr =
-      getMSPropertyAttr(D.getDeclSpec().getAttributes());
-
-  if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
-    // The Microsoft extension __interface only permits public member functions
-    // and prohibits constructors, destructors, operators, non-public member
-    // functions, static methods and data members.
-    unsigned InvalidDecl;
-    bool ShowDeclName = true;
-    if (!isFunc &&
-        (DS.getStorageClassSpec() == DeclSpec::SCS_typedef || MSPropertyAttr))
-      InvalidDecl = 0;
-    else if (!isFunc)
-      InvalidDecl = 1;
-    else if (AS != AS_public)
-      InvalidDecl = 2;
-    else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
-      InvalidDecl = 3;
-    else switch (Name.getNameKind()) {
-      case DeclarationName::CXXConstructorName:
-        InvalidDecl = 4;
-        ShowDeclName = false;
-        break;
-
-      case DeclarationName::CXXDestructorName:
-        InvalidDecl = 5;
-        ShowDeclName = false;
-        break;
-
-      case DeclarationName::CXXOperatorName:
-      case DeclarationName::CXXConversionFunctionName:
-        InvalidDecl = 6;
-        break;
-
-      default:
-        InvalidDecl = 0;
-        break;
-    }
-
-    if (InvalidDecl) {
-      if (ShowDeclName)
-        Diag(Loc, diag::err_invalid_member_in_interface)
-          << (InvalidDecl-1) << Name;
-      else
-        Diag(Loc, diag::err_invalid_member_in_interface)
-          << (InvalidDecl-1) << "";
-      return nullptr;
-    }
-  }
-
-  // C++ 9.2p6: A member shall not be declared to have automatic storage
-  // duration (auto, register) or with the extern storage-class-specifier.
-  // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
-  // data members and cannot be applied to names declared const or static,
-  // and cannot be applied to reference members.
-  switch (DS.getStorageClassSpec()) {
-  case DeclSpec::SCS_unspecified:
-  case DeclSpec::SCS_typedef:
-  case DeclSpec::SCS_static:
-    break;
-  case DeclSpec::SCS_mutable:
-    if (isFunc) {
-      Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
-
-      // FIXME: It would be nicer if the keyword was ignored only for this
-      // declarator. Otherwise we could get follow-up errors.
-      D.getMutableDeclSpec().ClearStorageClassSpecs();
-    }
-    break;
-  default:
-    Diag(DS.getStorageClassSpecLoc(),
-         diag::err_storageclass_invalid_for_member);
-    D.getMutableDeclSpec().ClearStorageClassSpecs();
-    break;
-  }
-
-  bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
-                       DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
-                      !isFunc);
-
-  if (DS.isConstexprSpecified() && isInstField) {
-    SemaDiagnosticBuilder B =
-        Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
-    SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
-    if (InitStyle == ICIS_NoInit) {
-      B << 0 << 0;
-      if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
-        B << FixItHint::CreateRemoval(ConstexprLoc);
-      else {
-        B << FixItHint::CreateReplacement(ConstexprLoc, "const");
-        D.getMutableDeclSpec().ClearConstexprSpec();
-        const char *PrevSpec;
-        unsigned DiagID;
-        bool Failed = D.getMutableDeclSpec().SetTypeQual(
-            DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
-        (void)Failed;
-        assert(!Failed && "Making a constexpr member const shouldn't fail");
-      }
-    } else {
-      B << 1;
-      const char *PrevSpec;
-      unsigned DiagID;
-      if (D.getMutableDeclSpec().SetStorageClassSpec(
-          *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
-          Context.getPrintingPolicy())) {
-        assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
-               "This is the only DeclSpec that should fail to be applied");
-        B << 1;
-      } else {
-        B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
-        isInstField = false;
-      }
-    }
-  }
-
-  NamedDecl *Member;
-  if (isInstField) {
-    CXXScopeSpec &SS = D.getCXXScopeSpec();
-
-    // Data members must have identifiers for names.
-    if (!Name.isIdentifier()) {
-      Diag(Loc, diag::err_bad_variable_name)
-        << Name;
-      return nullptr;
-    }
-
-    IdentifierInfo *II = Name.getAsIdentifierInfo();
-
-    // Member field could not be with "template" keyword.
-    // So TemplateParameterLists should be empty in this case.
-    if (TemplateParameterLists.size()) {
-      TemplateParameterList* TemplateParams = TemplateParameterLists[0];
-      if (TemplateParams->size()) {
-        // There is no such thing as a member field template.
-        Diag(D.getIdentifierLoc(), diag::err_template_member)
-            << II
-            << SourceRange(TemplateParams->getTemplateLoc(),
-                TemplateParams->getRAngleLoc());
-      } else {
-        // There is an extraneous 'template<>' for this member.
-        Diag(TemplateParams->getTemplateLoc(),
-            diag::err_template_member_noparams)
-            << II
-            << SourceRange(TemplateParams->getTemplateLoc(),
-                TemplateParams->getRAngleLoc());
-      }
-      return nullptr;
-    }
-
-    if (SS.isSet() && !SS.isInvalid()) {
-      // The user provided a superfluous scope specifier inside a class
-      // definition:
-      //
-      // class X {
-      //   int X::member;
-      // };
-      if (DeclContext *DC = computeDeclContext(SS, false))
-        diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc(),
-                                     D.getName().getKind() ==
-                                         UnqualifiedIdKind::IK_TemplateId);
-      else
-        Diag(D.getIdentifierLoc(), diag::err_member_qualification)
-          << Name << SS.getRange();
-
-      SS.clear();
-    }
-
-    if (MSPropertyAttr) {
-      Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
-                                BitWidth, InitStyle, AS, *MSPropertyAttr);
-      if (!Member)
-        return nullptr;
-      isInstField = false;
-    } else {
-      Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
-                                BitWidth, InitStyle, AS);
-      if (!Member)
-        return nullptr;
-    }
-
-    CheckShadowInheritedFields(Loc, Name, cast<CXXRecordDecl>(CurContext));
-  } else {
-    Member = HandleDeclarator(S, D, TemplateParameterLists);
-    if (!Member)
-      return nullptr;
-
-    // Non-instance-fields can't have a bitfield.
-    if (BitWidth) {
-      if (Member->isInvalidDecl()) {
-        // don't emit another diagnostic.
-      } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
-        // C++ 9.6p3: A bit-field shall not be a static member.
-        // "static member 'A' cannot be a bit-field"
-        Diag(Loc, diag::err_static_not_bitfield)
-          << Name << BitWidth->getSourceRange();
-      } else if (isa<TypedefDecl>(Member)) {
-        // "typedef member 'x' cannot be a bit-field"
-        Diag(Loc, diag::err_typedef_not_bitfield)
-          << Name << BitWidth->getSourceRange();
-      } else {
-        // A function typedef ("typedef int f(); f a;").
-        // C++ 9.6p3: A bit-field shall have integral or enumeration type.
-        Diag(Loc, diag::err_not_integral_type_bitfield)
-          << Name << cast<ValueDecl>(Member)->getType()
-          << BitWidth->getSourceRange();
-      }
-
-      BitWidth = nullptr;
-      Member->setInvalidDecl();
-    }
-
-    NamedDecl *NonTemplateMember = Member;
-    if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
-      NonTemplateMember = FunTmpl->getTemplatedDecl();
-    else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
-      NonTemplateMember = VarTmpl->getTemplatedDecl();
-
-    Member->setAccess(AS);
-
-    // If we have declared a member function template or static data member
-    // template, set the access of the templated declaration as well.
-    if (NonTemplateMember != Member)
-      NonTemplateMember->setAccess(AS);
-
-    // C++ [temp.deduct.guide]p3:
-    //   A deduction guide [...] for a member class template [shall be
-    //   declared] with the same access [as the template].
-    if (auto *DG = dyn_cast<CXXDeductionGuideDecl>(NonTemplateMember)) {
-      auto *TD = DG->getDeducedTemplate();
-      if (AS != TD->getAccess()) {
-        Diag(DG->getBeginLoc(), diag::err_deduction_guide_wrong_access);
-        Diag(TD->getBeginLoc(), diag::note_deduction_guide_template_access)
-            << TD->getAccess();
-        const AccessSpecDecl *LastAccessSpec = nullptr;
-        for (const auto *D : cast<CXXRecordDecl>(CurContext)->decls()) {
-          if (const auto *AccessSpec = dyn_cast<AccessSpecDecl>(D))
-            LastAccessSpec = AccessSpec;
-        }
-        assert(LastAccessSpec && "differing access with no access specifier");
-        Diag(LastAccessSpec->getBeginLoc(), diag::note_deduction_guide_access)
-            << AS;
-      }
-    }
-  }
-
-  if (VS.isOverrideSpecified())
-    Member->addAttr(new (Context) OverrideAttr(VS.getOverrideLoc(), Context, 0));
-  if (VS.isFinalSpecified())
-    Member->addAttr(new (Context) FinalAttr(VS.getFinalLoc(), Context,
-                                            VS.isFinalSpelledSealed()));
-
-  if (VS.getLastLocation().isValid()) {
-    // Update the end location of a method that has a virt-specifiers.
-    if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
-      MD->setRangeEnd(VS.getLastLocation());
-  }
-
-  CheckOverrideControl(Member);
-
-  assert((Name || isInstField) && "No identifier for non-field ?");
-
-  if (isInstField) {
-    FieldDecl *FD = cast<FieldDecl>(Member);
-    FieldCollector->Add(FD);
-
-    if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
-      // Remember all explicit private FieldDecls that have a name, no side
-      // effects and are not part of a dependent type declaration.
-      if (!FD->isImplicit() && FD->getDeclName() &&
-          FD->getAccess() == AS_private &&
-          !FD->hasAttr<UnusedAttr>() &&
-          !FD->getParent()->isDependentContext() &&
-          !InitializationHasSideEffects(*FD))
-        UnusedPrivateFields.insert(FD);
-    }
-  }
-
-  return Member;
-}
-
-namespace {
-  class UninitializedFieldVisitor
-      : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
-    Sema &S;
-    // List of Decls to generate a warning on.  Also remove Decls that become
-    // initialized.
-    llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
-    // List of base classes of the record.  Classes are removed after their
-    // initializers.
-    llvm::SmallPtrSetImpl<QualType> &BaseClasses;
-    // Vector of decls to be removed from the Decl set prior to visiting the
-    // nodes.  These Decls may have been initialized in the prior initializer.
-    llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
-    // If non-null, add a note to the warning pointing back to the constructor.
-    const CXXConstructorDecl *Constructor;
-    // Variables to hold state when processing an initializer list.  When
-    // InitList is true, special case initialization of FieldDecls matching
-    // InitListFieldDecl.
-    bool InitList;
-    FieldDecl *InitListFieldDecl;
-    llvm::SmallVector<unsigned, 4> InitFieldIndex;
-
-  public:
-    typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
-    UninitializedFieldVisitor(Sema &S,
-                              llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
-                              llvm::SmallPtrSetImpl<QualType> &BaseClasses)
-      : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
-        Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
-
-    // Returns true if the use of ME is not an uninitialized use.
-    bool IsInitListMemberExprInitialized(MemberExpr *ME,
-                                         bool CheckReferenceOnly) {
-      llvm::SmallVector<FieldDecl*, 4> Fields;
-      bool ReferenceField = false;
-      while (ME) {
-        FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
-        if (!FD)
-          return false;
-        Fields.push_back(FD);
-        if (FD->getType()->isReferenceType())
-          ReferenceField = true;
-        ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
-      }
-
-      // Binding a reference to an uninitialized field is not an
-      // uninitialized use.
-      if (CheckReferenceOnly && !ReferenceField)
-        return true;
-
-      llvm::SmallVector<unsigned, 4> UsedFieldIndex;
-      // Discard the first field since it is the field decl that is being
-      // initialized.
-      for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
-        UsedFieldIndex.push_back((*I)->getFieldIndex());
-      }
-
-      for (auto UsedIter = UsedFieldIndex.begin(),
-                UsedEnd = UsedFieldIndex.end(),
-                OrigIter = InitFieldIndex.begin(),
-                OrigEnd = InitFieldIndex.end();
-           UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
-        if (*UsedIter < *OrigIter)
-          return true;
-        if (*UsedIter > *OrigIter)
-          break;
-      }
-
-      return false;
-    }
-
-    void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
-                          bool AddressOf) {
-      if (isa<EnumConstantDecl>(ME->getMemberDecl()))
-        return;
-
-      // FieldME is the inner-most MemberExpr that is not an anonymous struct
-      // or union.
-      MemberExpr *FieldME = ME;
-
-      bool AllPODFields = FieldME->getType().isPODType(S.Context);
-
-      Expr *Base = ME;
-      while (MemberExpr *SubME =
-                 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
-
-        if (isa<VarDecl>(SubME->getMemberDecl()))
-          return;
-
-        if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
-          if (!FD->isAnonymousStructOrUnion())
-            FieldME = SubME;
-
-        if (!FieldME->getType().isPODType(S.Context))
-          AllPODFields = false;
-
-        Base = SubME->getBase();
-      }
-
-      if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts()))
-        return;
-
-      if (AddressOf && AllPODFields)
-        return;
-
-      ValueDecl* FoundVD = FieldME->getMemberDecl();
-
-      if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
-        while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
-          BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
-        }
-
-        if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
-          QualType T = BaseCast->getType();
-          if (T->isPointerType() &&
-              BaseClasses.count(T->getPointeeType())) {
-            S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
-                << T->getPointeeType() << FoundVD;
-          }
-        }
-      }
-
-      if (!Decls.count(FoundVD))
-        return;
-
-      const bool IsReference = FoundVD->getType()->isReferenceType();
-
-      if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
-        // Special checking for initializer lists.
-        if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
-          return;
-        }
-      } else {
-        // Prevent double warnings on use of unbounded references.
-        if (CheckReferenceOnly && !IsReference)
-          return;
-      }
-
-      unsigned diag = IsReference
-          ? diag::warn_reference_field_is_uninit
-          : diag::warn_field_is_uninit;
-      S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
-      if (Constructor)
-        S.Diag(Constructor->getLocation(),
-               diag::note_uninit_in_this_constructor)
-          << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
-
-    }
-
-    void HandleValue(Expr *E, bool AddressOf) {
-      E = E->IgnoreParens();
-
-      if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
-        HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
-                         AddressOf /*AddressOf*/);
-        return;
-      }
-
-      if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
-        Visit(CO->getCond());
-        HandleValue(CO->getTrueExpr(), AddressOf);
-        HandleValue(CO->getFalseExpr(), AddressOf);
-        return;
-      }
-
-      if (BinaryConditionalOperator *BCO =
-              dyn_cast<BinaryConditionalOperator>(E)) {
-        Visit(BCO->getCond());
-        HandleValue(BCO->getFalseExpr(), AddressOf);
-        return;
-      }
-
-      if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
-        HandleValue(OVE->getSourceExpr(), AddressOf);
-        return;
-      }
-
-      if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
-        switch (BO->getOpcode()) {
-        default:
-          break;
-        case(BO_PtrMemD):
-        case(BO_PtrMemI):
-          HandleValue(BO->getLHS(), AddressOf);
-          Visit(BO->getRHS());
-          return;
-        case(BO_Comma):
-          Visit(BO->getLHS());
-          HandleValue(BO->getRHS(), AddressOf);
-          return;
-        }
-      }
-
-      Visit(E);
-    }
-
-    void CheckInitListExpr(InitListExpr *ILE) {
-      InitFieldIndex.push_back(0);
-      for (auto Child : ILE->children()) {
-        if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
-          CheckInitListExpr(SubList);
-        } else {
-          Visit(Child);
-        }
-        ++InitFieldIndex.back();
-      }
-      InitFieldIndex.pop_back();
-    }
-
-    void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
-                          FieldDecl *Field, const Type *BaseClass) {
-      // Remove Decls that may have been initialized in the previous
-      // initializer.
-      for (ValueDecl* VD : DeclsToRemove)
-        Decls.erase(VD);
-      DeclsToRemove.clear();
-
-      Constructor = FieldConstructor;
-      InitListExpr *ILE = dyn_cast<InitListExpr>(E);
-
-      if (ILE && Field) {
-        InitList = true;
-        InitListFieldDecl = Field;
-        InitFieldIndex.clear();
-        CheckInitListExpr(ILE);
-      } else {
-        InitList = false;
-        Visit(E);
-      }
-
-      if (Field)
-        Decls.erase(Field);
-      if (BaseClass)
-        BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
-    }
-
-    void VisitMemberExpr(MemberExpr *ME) {
-      // All uses of unbounded reference fields will warn.
-      HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
-    }
-
-    void VisitImplicitCastExpr(ImplicitCastExpr *E) {
-      if (E->getCastKind() == CK_LValueToRValue) {
-        HandleValue(E->getSubExpr(), false /*AddressOf*/);
-        return;
-      }
-
-      Inherited::VisitImplicitCastExpr(E);
-    }
-
-    void VisitCXXConstructExpr(CXXConstructExpr *E) {
-      if (E->getConstructor()->isCopyConstructor()) {
-        Expr *ArgExpr = E->getArg(0);
-        if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
-          if (ILE->getNumInits() == 1)
-            ArgExpr = ILE->getInit(0);
-        if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
-          if (ICE->getCastKind() == CK_NoOp)
-            ArgExpr = ICE->getSubExpr();
-        HandleValue(ArgExpr, false /*AddressOf*/);
-        return;
-      }
-      Inherited::VisitCXXConstructExpr(E);
-    }
-
-    void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
-      Expr *Callee = E->getCallee();
-      if (isa<MemberExpr>(Callee)) {
-        HandleValue(Callee, false /*AddressOf*/);
-        for (auto Arg : E->arguments())
-          Visit(Arg);
-        return;
-      }
-
-      Inherited::VisitCXXMemberCallExpr(E);
-    }
-
-    void VisitCallExpr(CallExpr *E) {
-      // Treat std::move as a use.
-      if (E->isCallToStdMove()) {
-        HandleValue(E->getArg(0), /*AddressOf=*/false);
-        return;
-      }
-
-      Inherited::VisitCallExpr(E);
-    }
-
-    void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
-      Expr *Callee = E->getCallee();
-
-      if (isa<UnresolvedLookupExpr>(Callee))
-        return Inherited::VisitCXXOperatorCallExpr(E);
-
-      Visit(Callee);
-      for (auto Arg : E->arguments())
-        HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
-    }
-
-    void VisitBinaryOperator(BinaryOperator *E) {
-      // If a field assignment is detected, remove the field from the
-      // uninitiailized field set.
-      if (E->getOpcode() == BO_Assign)
-        if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
-          if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
-            if (!FD->getType()->isReferenceType())
-              DeclsToRemove.push_back(FD);
-
-      if (E->isCompoundAssignmentOp()) {
-        HandleValue(E->getLHS(), false /*AddressOf*/);
-        Visit(E->getRHS());
-        return;
-      }
-
-      Inherited::VisitBinaryOperator(E);
-    }
-
-    void VisitUnaryOperator(UnaryOperator *E) {
-      if (E->isIncrementDecrementOp()) {
-        HandleValue(E->getSubExpr(), false /*AddressOf*/);
-        return;
-      }
-      if (E->getOpcode() == UO_AddrOf) {
-        if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
-          HandleValue(ME->getBase(), true /*AddressOf*/);
-          return;
-        }
-      }
-
-      Inherited::VisitUnaryOperator(E);
-    }
-  };
-
-  // Diagnose value-uses of fields to initialize themselves, e.g.
-  //   foo(foo)
-  // where foo is not also a parameter to the constructor.
-  // Also diagnose across field uninitialized use such as
-  //   x(y), y(x)
-  // TODO: implement -Wuninitialized and fold this into that framework.
-  static void DiagnoseUninitializedFields(
-      Sema &SemaRef, const CXXConstructorDecl *Constructor) {
-
-    if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
-                                           Constructor->getLocation())) {
-      return;
-    }
-
-    if (Constructor->isInvalidDecl())
-      return;
-
-    const CXXRecordDecl *RD = Constructor->getParent();
-
-    if (RD->getDescribedClassTemplate())
-      return;
-
-    // Holds fields that are uninitialized.
-    llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
-
-    // At the beginning, all fields are uninitialized.
-    for (auto *I : RD->decls()) {
-      if (auto *FD = dyn_cast<FieldDecl>(I)) {
-        UninitializedFields.insert(FD);
-      } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
-        UninitializedFields.insert(IFD->getAnonField());
-      }
-    }
-
-    llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
-    for (auto I : RD->bases())
-      UninitializedBaseClasses.insert(I.getType().getCanonicalType());
-
-    if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
-      return;
-
-    UninitializedFieldVisitor UninitializedChecker(SemaRef,
-                                                   UninitializedFields,
-                                                   UninitializedBaseClasses);
-
-    for (const auto *FieldInit : Constructor->inits()) {
-      if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
-        break;
-
-      Expr *InitExpr = FieldInit->getInit();
-      if (!InitExpr)
-        continue;
-
-      if (CXXDefaultInitExpr *Default =
-              dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
-        InitExpr = Default->getExpr();
-        if (!InitExpr)
-          continue;
-        // In class initializers will point to the constructor.
-        UninitializedChecker.CheckInitializer(InitExpr, Constructor,
-                                              FieldInit->getAnyMember(),
-                                              FieldInit->getBaseClass());
-      } else {
-        UninitializedChecker.CheckInitializer(InitExpr, nullptr,
-                                              FieldInit->getAnyMember(),
-                                              FieldInit->getBaseClass());
-      }
-    }
-  }
-} // namespace
-
-/// Enter a new C++ default initializer scope. After calling this, the
-/// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
-/// parsing or instantiating the initializer failed.
-void Sema::ActOnStartCXXInClassMemberInitializer() {
-  // Create a synthetic function scope to represent the call to the constructor
-  // that notionally surrounds a use of this initializer.
-  PushFunctionScope();
-}
-
-/// This is invoked after parsing an in-class initializer for a
-/// non-static C++ class member, and after instantiating an in-class initializer
-/// in a class template. Such actions are deferred until the class is complete.
-void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
-                                                  SourceLocation InitLoc,
-                                                  Expr *InitExpr) {
-  // Pop the notional constructor scope we created earlier.
-  PopFunctionScopeInfo(nullptr, D);
-
-  FieldDecl *FD = dyn_cast<FieldDecl>(D);
-  assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&
-         "must set init style when field is created");
-
-  if (!InitExpr) {
-    D->setInvalidDecl();
-    if (FD)
-      FD->removeInClassInitializer();
-    return;
-  }
-
-  if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
-    FD->setInvalidDecl();
-    FD->removeInClassInitializer();
-    return;
-  }
-
-  ExprResult Init = InitExpr;
-  if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
-    InitializedEntity Entity =
-        InitializedEntity::InitializeMemberFromDefaultMemberInitializer(FD);
-    InitializationKind Kind =
-        FD->getInClassInitStyle() == ICIS_ListInit
-            ? InitializationKind::CreateDirectList(InitExpr->getBeginLoc(),
-                                                   InitExpr->getBeginLoc(),
-                                                   InitExpr->getEndLoc())
-            : InitializationKind::CreateCopy(InitExpr->getBeginLoc(), InitLoc);
-    InitializationSequence Seq(*this, Entity, Kind, InitExpr);
-    Init = Seq.Perform(*this, Entity, Kind, InitExpr);
-    if (Init.isInvalid()) {
-      FD->setInvalidDecl();
-      return;
-    }
-  }
-
-  // C++11 [class.base.init]p7:
-  //   The initialization of each base and member constitutes a
-  //   full-expression.
-  Init = ActOnFinishFullExpr(Init.get(), InitLoc);
-  if (Init.isInvalid()) {
-    FD->setInvalidDecl();
-    return;
-  }
-
-  InitExpr = Init.get();
-
-  FD->setInClassInitializer(InitExpr);
-}
-
-/// Find the direct and/or virtual base specifiers that
-/// correspond to the given base type, for use in base initialization
-/// within a constructor.
-static bool FindBaseInitializer(Sema &SemaRef,
-                                CXXRecordDecl *ClassDecl,
-                                QualType BaseType,
-                                const CXXBaseSpecifier *&DirectBaseSpec,
-                                const CXXBaseSpecifier *&VirtualBaseSpec) {
-  // First, check for a direct base class.
-  DirectBaseSpec = nullptr;
-  for (const auto &Base : ClassDecl->bases()) {
-    if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
-      // We found a direct base of this type. That's what we're
-      // initializing.
-      DirectBaseSpec = &Base;
-      break;
-    }
-  }
-
-  // Check for a virtual base class.
-  // FIXME: We might be able to short-circuit this if we know in advance that
-  // there are no virtual bases.
-  VirtualBaseSpec = nullptr;
-  if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
-    // We haven't found a base yet; search the class hierarchy for a
-    // virtual base class.
-    CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
-                       /*DetectVirtual=*/false);
-    if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
-                              SemaRef.Context.getTypeDeclType(ClassDecl),
-                              BaseType, Paths)) {
-      for (CXXBasePaths::paths_iterator Path = Paths.begin();
-           Path != Paths.end(); ++Path) {
-        if (Path->back().Base->isVirtual()) {
-          VirtualBaseSpec = Path->back().Base;
-          break;
-        }
-      }
-    }
-  }
-
-  return DirectBaseSpec || VirtualBaseSpec;
-}
-
-/// Handle a C++ member initializer using braced-init-list syntax.
-MemInitResult
-Sema::ActOnMemInitializer(Decl *ConstructorD,
-                          Scope *S,
-                          CXXScopeSpec &SS,
-                          IdentifierInfo *MemberOrBase,
-                          ParsedType TemplateTypeTy,
-                          const DeclSpec &DS,
-                          SourceLocation IdLoc,
-                          Expr *InitList,
-                          SourceLocation EllipsisLoc) {
-  return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
-                             DS, IdLoc, InitList,
-                             EllipsisLoc);
-}
-
-/// Handle a C++ member initializer using parentheses syntax.
-MemInitResult
-Sema::ActOnMemInitializer(Decl *ConstructorD,
-                          Scope *S,
-                          CXXScopeSpec &SS,
-                          IdentifierInfo *MemberOrBase,
-                          ParsedType TemplateTypeTy,
-                          const DeclSpec &DS,
-                          SourceLocation IdLoc,
-                          SourceLocation LParenLoc,
-                          ArrayRef<Expr *> Args,
-                          SourceLocation RParenLoc,
-                          SourceLocation EllipsisLoc) {
-  Expr *List = ParenListExpr::Create(Context, LParenLoc, Args, RParenLoc);
-  return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
-                             DS, IdLoc, List, EllipsisLoc);
-}
-
-namespace {
-
-// Callback to only accept typo corrections that can be a valid C++ member
-// intializer: either a non-static field member or a base class.
-class MemInitializerValidatorCCC : public CorrectionCandidateCallback {
-public:
-  explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
-      : ClassDecl(ClassDecl) {}
-
-  bool ValidateCandidate(const TypoCorrection &candidate) override {
-    if (NamedDecl *ND = candidate.getCorrectionDecl()) {
-      if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
-        return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
-      return isa<TypeDecl>(ND);
-    }
-    return false;
-  }
-
-private:
-  CXXRecordDecl *ClassDecl;
-};
-
-}
-
-ValueDecl *Sema::tryLookupCtorInitMemberDecl(CXXRecordDecl *ClassDecl,
-                                             CXXScopeSpec &SS,
-                                             ParsedType TemplateTypeTy,
-                                             IdentifierInfo *MemberOrBase) {
-  if (SS.getScopeRep() || TemplateTypeTy)
-    return nullptr;
-  DeclContext::lookup_result Result = ClassDecl->lookup(MemberOrBase);
-  if (Result.empty())
-    return nullptr;
-  ValueDecl *Member;
-  if ((Member = dyn_cast<FieldDecl>(Result.front())) ||
-      (Member = dyn_cast<IndirectFieldDecl>(Result.front())))
-    return Member;
-  return nullptr;
-}
-
-/// Handle a C++ member initializer.
-MemInitResult
-Sema::BuildMemInitializer(Decl *ConstructorD,
-                          Scope *S,
-                          CXXScopeSpec &SS,
-                          IdentifierInfo *MemberOrBase,
-                          ParsedType TemplateTypeTy,
-                          const DeclSpec &DS,
-                          SourceLocation IdLoc,
-                          Expr *Init,
-                          SourceLocation EllipsisLoc) {
-  ExprResult Res = CorrectDelayedTyposInExpr(Init);
-  if (!Res.isUsable())
-    return true;
-  Init = Res.get();
-
-  if (!ConstructorD)
-    return true;
-
-  AdjustDeclIfTemplate(ConstructorD);
-
-  CXXConstructorDecl *Constructor
-    = dyn_cast<CXXConstructorDecl>(ConstructorD);
-  if (!Constructor) {
-    // The user wrote a constructor initializer on a function that is
-    // not a C++ constructor. Ignore the error for now, because we may
-    // have more member initializers coming; we'll diagnose it just
-    // once in ActOnMemInitializers.
-    return true;
-  }
-
-  CXXRecordDecl *ClassDecl = Constructor->getParent();
-
-  // C++ [class.base.init]p2:
-  //   Names in a mem-initializer-id are looked up in the scope of the
-  //   constructor's class and, if not found in that scope, are looked
-  //   up in the scope containing the constructor's definition.
-  //   [Note: if the constructor's class contains a member with the
-  //   same name as a direct or virtual base class of the class, a
-  //   mem-initializer-id naming the member or base class and composed
-  //   of a single identifier refers to the class member. A
-  //   mem-initializer-id for the hidden base class may be specified
-  //   using a qualified name. ]
-
-  // Look for a member, first.
-  if (ValueDecl *Member = tryLookupCtorInitMemberDecl(
-          ClassDecl, SS, TemplateTypeTy, MemberOrBase)) {
-    if (EllipsisLoc.isValid())
-      Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
-          << MemberOrBase
-          << SourceRange(IdLoc, Init->getSourceRange().getEnd());
-
-    return BuildMemberInitializer(Member, Init, IdLoc);
-  }
-  // It didn't name a member, so see if it names a class.
-  QualType BaseType;
-  TypeSourceInfo *TInfo = nullptr;
-
-  if (TemplateTypeTy) {
-    BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
-  } else if (DS.getTypeSpecType() == TST_decltype) {
-    BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
-  } else if (DS.getTypeSpecType() == TST_decltype_auto) {
-    Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
-    return true;
-  } else {
-    LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
-    LookupParsedName(R, S, &SS);
-
-    TypeDecl *TyD = R.getAsSingle<TypeDecl>();
-    if (!TyD) {
-      if (R.isAmbiguous()) return true;
-
-      // We don't want access-control diagnostics here.
-      R.suppressDiagnostics();
-
-      if (SS.isSet() && isDependentScopeSpecifier(SS)) {
-        bool NotUnknownSpecialization = false;
-        DeclContext *DC = computeDeclContext(SS, false);
-        if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
-          NotUnknownSpecialization = !Record->hasAnyDependentBases();
-
-        if (!NotUnknownSpecialization) {
-          // When the scope specifier can refer to a member of an unknown
-          // specialization, we take it as a type name.
-          BaseType = CheckTypenameType(ETK_None, SourceLocation(),
-                                       SS.getWithLocInContext(Context),
-                                       *MemberOrBase, IdLoc);
-          if (BaseType.isNull())
-            return true;
-
-          TInfo = Context.CreateTypeSourceInfo(BaseType);
-          DependentNameTypeLoc TL =
-              TInfo->getTypeLoc().castAs<DependentNameTypeLoc>();
-          if (!TL.isNull()) {
-            TL.setNameLoc(IdLoc);
-            TL.setElaboratedKeywordLoc(SourceLocation());
-            TL.setQualifierLoc(SS.getWithLocInContext(Context));
-          }
-
-          R.clear();
-          R.setLookupName(MemberOrBase);
-        }
-      }
-
-      // If no results were found, try to correct typos.
-      TypoCorrection Corr;
-      if (R.empty() && BaseType.isNull() &&
-          (Corr = CorrectTypo(
-               R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
-               llvm::make_unique<MemInitializerValidatorCCC>(ClassDecl),
-               CTK_ErrorRecovery, ClassDecl))) {
-        if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
-          // We have found a non-static data member with a similar
-          // name to what was typed; complain and initialize that
-          // member.
-          diagnoseTypo(Corr,
-                       PDiag(diag::err_mem_init_not_member_or_class_suggest)
-                         << MemberOrBase << true);
-          return BuildMemberInitializer(Member, Init, IdLoc);
-        } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
-          const CXXBaseSpecifier *DirectBaseSpec;
-          const CXXBaseSpecifier *VirtualBaseSpec;
-          if (FindBaseInitializer(*this, ClassDecl,
-                                  Context.getTypeDeclType(Type),
-                                  DirectBaseSpec, VirtualBaseSpec)) {
-            // We have found a direct or virtual base class with a
-            // similar name to what was typed; complain and initialize
-            // that base class.
-            diagnoseTypo(Corr,
-                         PDiag(diag::err_mem_init_not_member_or_class_suggest)
-                           << MemberOrBase << false,
-                         PDiag() /*Suppress note, we provide our own.*/);
-
-            const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
-                                                              : VirtualBaseSpec;
-            Diag(BaseSpec->getBeginLoc(), diag::note_base_class_specified_here)
-                << BaseSpec->getType() << BaseSpec->getSourceRange();
-
-            TyD = Type;
-          }
-        }
-      }
-
-      if (!TyD && BaseType.isNull()) {
-        Diag(IdLoc, diag::err_mem_init_not_member_or_class)
-          << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
-        return true;
-      }
-    }
-
-    if (BaseType.isNull()) {
-      BaseType = Context.getTypeDeclType(TyD);
-      MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
-      if (SS.isSet()) {
-        BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
-                                             BaseType);
-        TInfo = Context.CreateTypeSourceInfo(BaseType);
-        ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
-        TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
-        TL.setElaboratedKeywordLoc(SourceLocation());
-        TL.setQualifierLoc(SS.getWithLocInContext(Context));
-      }
-    }
-  }
-
-  if (!TInfo)
-    TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
-
-  return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
-}
-
-MemInitResult
-Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
-                             SourceLocation IdLoc) {
-  FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
-  IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
-  assert((DirectMember || IndirectMember) &&
-         "Member must be a FieldDecl or IndirectFieldDecl");
-
-  if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
-    return true;
-
-  if (Member->isInvalidDecl())
-    return true;
-
-  MultiExprArg Args;
-  if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
-    Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
-  } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
-    Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
-  } else {
-    // Template instantiation doesn't reconstruct ParenListExprs for us.
-    Args = Init;
-  }
-
-  SourceRange InitRange = Init->getSourceRange();
-
-  if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
-    // Can't check initialization for a member of dependent type or when
-    // any of the arguments are type-dependent expressions.
-    DiscardCleanupsInEvaluationContext();
-  } else {
-    bool InitList = false;
-    if (isa<InitListExpr>(Init)) {
-      InitList = true;
-      Args = Init;
-    }
-
-    // Initialize the member.
-    InitializedEntity MemberEntity =
-      DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
-                   : InitializedEntity::InitializeMember(IndirectMember,
-                                                         nullptr);
-    InitializationKind Kind =
-        InitList ? InitializationKind::CreateDirectList(
-                       IdLoc, Init->getBeginLoc(), Init->getEndLoc())
-                 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
-                                                    InitRange.getEnd());
-
-    InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
-    ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
-                                            nullptr);
-    if (MemberInit.isInvalid())
-      return true;
-
-    // C++11 [class.base.init]p7:
-    //   The initialization of each base and member constitutes a
-    //   full-expression.
-    MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin());
-    if (MemberInit.isInvalid())
-      return true;
-
-    Init = MemberInit.get();
-  }
-
-  if (DirectMember) {
-    return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
-                                            InitRange.getBegin(), Init,
-                                            InitRange.getEnd());
-  } else {
-    return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
-                                            InitRange.getBegin(), Init,
-                                            InitRange.getEnd());
-  }
-}
-
-MemInitResult
-Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
-                                 CXXRecordDecl *ClassDecl) {
-  SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
-  if (!LangOpts.CPlusPlus11)
-    return Diag(NameLoc, diag::err_delegating_ctor)
-      << TInfo->getTypeLoc().getLocalSourceRange();
-  Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
-
-  bool InitList = true;
-  MultiExprArg Args = Init;
-  if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
-    InitList = false;
-    Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
-  }
-
-  SourceRange InitRange = Init->getSourceRange();
-  // Initialize the object.
-  InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
-                                     QualType(ClassDecl->getTypeForDecl(), 0));
-  InitializationKind Kind =
-      InitList ? InitializationKind::CreateDirectList(
-                     NameLoc, Init->getBeginLoc(), Init->getEndLoc())
-               : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
-                                                  InitRange.getEnd());
-  InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
-  ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
-                                              Args, nullptr);
-  if (DelegationInit.isInvalid())
-    return true;
-
-  assert(cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() &&
-         "Delegating constructor with no target?");
-
-  // C++11 [class.base.init]p7:
-  //   The initialization of each base and member constitutes a
-  //   full-expression.
-  DelegationInit = ActOnFinishFullExpr(DelegationInit.get(),
-                                       InitRange.getBegin());
-  if (DelegationInit.isInvalid())
-    return true;
-
-  // If we are in a dependent context, template instantiation will
-  // perform this type-checking again. Just save the arguments that we
-  // received in a ParenListExpr.
-  // FIXME: This isn't quite ideal, since our ASTs don't capture all
-  // of the information that we have about the base
-  // initializer. However, deconstructing the ASTs is a dicey process,
-  // and this approach is far more likely to get the corner cases right.
-  if (CurContext->isDependentContext())
-    DelegationInit = Init;
-
-  return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
-                                          DelegationInit.getAs<Expr>(),
-                                          InitRange.getEnd());
-}
-
-MemInitResult
-Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
-                           Expr *Init, CXXRecordDecl *ClassDecl,
-                           SourceLocation EllipsisLoc) {
-  SourceLocation BaseLoc
-    = BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
-
-  if (!BaseType->isDependentType() && !BaseType->isRecordType())
-    return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
-             << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
-
-  // C++ [class.base.init]p2:
-  //   [...] Unless the mem-initializer-id names a nonstatic data
-  //   member of the constructor's class or a direct or virtual base
-  //   of that class, the mem-initializer is ill-formed. A
-  //   mem-initializer-list can initialize a base class using any
-  //   name that denotes that base class type.
-  bool Dependent = BaseType->isDependentType() || Init->isTypeDependent();
-
-  SourceRange InitRange = Init->getSourceRange();
-  if (EllipsisLoc.isValid()) {
-    // This is a pack expansion.
-    if (!BaseType->containsUnexpandedParameterPack())  {
-      Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
-        << SourceRange(BaseLoc, InitRange.getEnd());
-
-      EllipsisLoc = SourceLocation();
-    }
-  } else {
-    // Check for any unexpanded parameter packs.
-    if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
-      return true;
-
-    if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
-      return true;
-  }
-
-  // Check for direct and virtual base classes.
-  const CXXBaseSpecifier *DirectBaseSpec = nullptr;
-  const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
-  if (!Dependent) {
-    if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
-                                       BaseType))
-      return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
-
-    FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
-                        VirtualBaseSpec);
-
-    // C++ [base.class.init]p2:
-    // Unless the mem-initializer-id names a nonstatic data member of the
-    // constructor's class or a direct or virtual base of that class, the
-    // mem-initializer is ill-formed.
-    if (!DirectBaseSpec && !VirtualBaseSpec) {
-      // If the class has any dependent bases, then it's possible that
-      // one of those types will resolve to the same type as
-      // BaseType. Therefore, just treat this as a dependent base
-      // class initialization.  FIXME: Should we try to check the
-      // initialization anyway? It seems odd.
-      if (ClassDecl->hasAnyDependentBases())
-        Dependent = true;
-      else
-        return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
-          << BaseType << Context.getTypeDeclType(ClassDecl)
-          << BaseTInfo->getTypeLoc().getLocalSourceRange();
-    }
-  }
-
-  if (Dependent) {
-    DiscardCleanupsInEvaluationContext();
-
-    return new (Context) CXXCtorInitializer(Context, BaseTInfo,
-                                            /*IsVirtual=*/false,
-                                            InitRange.getBegin(), Init,
-                                            InitRange.getEnd(), EllipsisLoc);
-  }
-
-  // C++ [base.class.init]p2:
-  //   If a mem-initializer-id is ambiguous because it designates both
-  //   a direct non-virtual base class and an inherited virtual base
-  //   class, the mem-initializer is ill-formed.
-  if (DirectBaseSpec && VirtualBaseSpec)
-    return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
-      << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
-
-  const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
-  if (!BaseSpec)
-    BaseSpec = VirtualBaseSpec;
-
-  // Initialize the base.
-  bool InitList = true;
-  MultiExprArg Args = Init;
-  if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
-    InitList = false;
-    Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
-  }
-
-  InitializedEntity BaseEntity =
-    InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
-  InitializationKind Kind =
-      InitList ? InitializationKind::CreateDirectList(BaseLoc)
-               : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
-                                                  InitRange.getEnd());
-  InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
-  ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
-  if (BaseInit.isInvalid())
-    return true;
-
-  // C++11 [class.base.init]p7:
-  //   The initialization of each base and member constitutes a
-  //   full-expression.
-  BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin());
-  if (BaseInit.isInvalid())
-    return true;
-
-  // If we are in a dependent context, template instantiation will
-  // perform this type-checking again. Just save the arguments that we
-  // received in a ParenListExpr.
-  // FIXME: This isn't quite ideal, since our ASTs don't capture all
-  // of the information that we have about the base
-  // initializer. However, deconstructing the ASTs is a dicey process,
-  // and this approach is far more likely to get the corner cases right.
-  if (CurContext->isDependentContext())
-    BaseInit = Init;
-
-  return new (Context) CXXCtorInitializer(Context, BaseTInfo,
-                                          BaseSpec->isVirtual(),
-                                          InitRange.getBegin(),
-                                          BaseInit.getAs<Expr>(),
-                                          InitRange.getEnd(), EllipsisLoc);
-}
-
-// Create a static_cast\<T&&>(expr).
-static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
-  if (T.isNull()) T = E->getType();
-  QualType TargetType = SemaRef.BuildReferenceType(
-      T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
-  SourceLocation ExprLoc = E->getBeginLoc();
-  TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
-      TargetType, ExprLoc);
-
-  return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
-                                   SourceRange(ExprLoc, ExprLoc),
-                                   E->getSourceRange()).get();
-}
-
-/// ImplicitInitializerKind - How an implicit base or member initializer should
-/// initialize its base or member.
-enum ImplicitInitializerKind {
-  IIK_Default,
-  IIK_Copy,
-  IIK_Move,
-  IIK_Inherit
-};
-
-static bool
-BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
-                             ImplicitInitializerKind ImplicitInitKind,
-                             CXXBaseSpecifier *BaseSpec,
-                             bool IsInheritedVirtualBase,
-                             CXXCtorInitializer *&CXXBaseInit) {
-  InitializedEntity InitEntity
-    = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
-                                        IsInheritedVirtualBase);
-
-  ExprResult BaseInit;
-
-  switch (ImplicitInitKind) {
-  case IIK_Inherit:
-  case IIK_Default: {
-    InitializationKind InitKind
-      = InitializationKind::CreateDefault(Constructor->getLocation());
-    InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
-    BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
-    break;
-  }
-
-  case IIK_Move:
-  case IIK_Copy: {
-    bool Moving = ImplicitInitKind == IIK_Move;
-    ParmVarDecl *Param = Constructor->getParamDecl(0);
-    QualType ParamType = Param->getType().getNonReferenceType();
-
-    Expr *CopyCtorArg =
-      DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
-                          SourceLocation(), Param, false,
-                          Constructor->getLocation(), ParamType,
-                          VK_LValue, nullptr);
-
-    SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
-
-    // Cast to the base class to avoid ambiguities.
-    QualType ArgTy =
-      SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
-                                       ParamType.getQualifiers());
-
-    if (Moving) {
-      CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
-    }
-
-    CXXCastPath BasePath;
-    BasePath.push_back(BaseSpec);
-    CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
-                                            CK_UncheckedDerivedToBase,
-                                            Moving ? VK_XValue : VK_LValue,
-                                            &BasePath).get();
-
-    InitializationKind InitKind
-      = InitializationKind::CreateDirect(Constructor->getLocation(),
-                                         SourceLocation(), SourceLocation());
-    InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
-    BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
-    break;
-  }
-  }
-
-  BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
-  if (BaseInit.isInvalid())
-    return true;
-
-  CXXBaseInit =
-    new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
-               SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
-                                                        SourceLocation()),
-                                             BaseSpec->isVirtual(),
-                                             SourceLocation(),
-                                             BaseInit.getAs<Expr>(),
-                                             SourceLocation(),
-                                             SourceLocation());
-
-  return false;
-}
-
-static bool RefersToRValueRef(Expr *MemRef) {
-  ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
-  return Referenced->getType()->isRValueReferenceType();
-}
-
-static bool
-BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
-                               ImplicitInitializerKind ImplicitInitKind,
-                               FieldDecl *Field, IndirectFieldDecl *Indirect,
-                               CXXCtorInitializer *&CXXMemberInit) {
-  if (Field->isInvalidDecl())
-    return true;
-
-  SourceLocation Loc = Constructor->getLocation();
-
-  if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
-    bool Moving = ImplicitInitKind == IIK_Move;
-    ParmVarDecl *Param = Constructor->getParamDecl(0);
-    QualType ParamType = Param->getType().getNonReferenceType();
-
-    // Suppress copying zero-width bitfields.
-    if (Field->isZeroLengthBitField(SemaRef.Context))
-      return false;
-
-    Expr *MemberExprBase =
-      DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
-                          SourceLocation(), Param, false,
-                          Loc, ParamType, VK_LValue, nullptr);
-
-    SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
-
-    if (Moving) {
-      MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
-    }
-
-    // Build a reference to this field within the parameter.
-    CXXScopeSpec SS;
-    LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
-                              Sema::LookupMemberName);
-    MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
-                                  : cast<ValueDecl>(Field), AS_public);
-    MemberLookup.resolveKind();
-    ExprResult CtorArg
-      = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
-                                         ParamType, Loc,
-                                         /*IsArrow=*/false,
-                                         SS,
-                                         /*TemplateKWLoc=*/SourceLocation(),
-                                         /*FirstQualifierInScope=*/nullptr,
-                                         MemberLookup,
-                                         /*TemplateArgs=*/nullptr,
-                                         /*S*/nullptr);
-    if (CtorArg.isInvalid())
-      return true;
-
-    // C++11 [class.copy]p15:
-    //   - if a member m has rvalue reference type T&&, it is direct-initialized
-    //     with static_cast<T&&>(x.m);
-    if (RefersToRValueRef(CtorArg.get())) {
-      CtorArg = CastForMoving(SemaRef, CtorArg.get());
-    }
-
-    InitializedEntity Entity =
-        Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
-                                                       /*Implicit*/ true)
-                 : InitializedEntity::InitializeMember(Field, nullptr,
-                                                       /*Implicit*/ true);
-
-    // Direct-initialize to use the copy constructor.
-    InitializationKind InitKind =
-      InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
-
-    Expr *CtorArgE = CtorArg.getAs<Expr>();
-    InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
-    ExprResult MemberInit =
-        InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
-    MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
-    if (MemberInit.isInvalid())
-      return true;
-
-    if (Indirect)
-      CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
-          SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
-    else
-      CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
-          SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
-    return false;
-  }
-
-  assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&
-         "Unhandled implicit init kind!");
-
-  QualType FieldBaseElementType =
-    SemaRef.Context.getBaseElementType(Field->getType());
-
-  if (FieldBaseElementType->isRecordType()) {
-    InitializedEntity InitEntity =
-        Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
-                                                       /*Implicit*/ true)
-                 : InitializedEntity::InitializeMember(Field, nullptr,
-                                                       /*Implicit*/ true);
-    InitializationKind InitKind =
-      InitializationKind::CreateDefault(Loc);
-
-    InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
-    ExprResult MemberInit =
-      InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
-
-    MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
-    if (MemberInit.isInvalid())
-      return true;
-
-    if (Indirect)
-      CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
-                                                               Indirect, Loc,
-                                                               Loc,
-                                                               MemberInit.get(),
-                                                               Loc);
-    else
-      CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
-                                                               Field, Loc, Loc,
-                                                               MemberInit.get(),
-                                                               Loc);
-    return false;
-  }
-
-  if (!Field->getParent()->isUnion()) {
-    if (FieldBaseElementType->isReferenceType()) {
-      SemaRef.Diag(Constructor->getLocation(),
-                   diag::err_uninitialized_member_in_ctor)
-      << (int)Constructor->isImplicit()
-      << SemaRef.Context.getTagDeclType(Constructor->getParent())
-      << 0 << Field->getDeclName();
-      SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
-      return true;
-    }
-
-    if (FieldBaseElementType.isConstQualified()) {
-      SemaRef.Diag(Constructor->getLocation(),
-                   diag::err_uninitialized_member_in_ctor)
-      << (int)Constructor->isImplicit()
-      << SemaRef.Context.getTagDeclType(Constructor->getParent())
-      << 1 << Field->getDeclName();
-      SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
-      return true;
-    }
-  }
-
-  if (FieldBaseElementType.hasNonTrivialObjCLifetime()) {
-    // ARC and Weak:
-    //   Default-initialize Objective-C pointers to NULL.
-    CXXMemberInit
-      = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
-                                                 Loc, Loc,
-                 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
-                                                 Loc);
-    return false;
-  }
-
-  // Nothing to initialize.
-  CXXMemberInit = nullptr;
-  return false;
-}
-
-namespace {
-struct BaseAndFieldInfo {
-  Sema &S;
-  CXXConstructorDecl *Ctor;
-  bool AnyErrorsInInits;
-  ImplicitInitializerKind IIK;
-  llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
-  SmallVector<CXXCtorInitializer*, 8> AllToInit;
-  llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
-
-  BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
-    : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
-    bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
-    if (Ctor->getInheritedConstructor())
-      IIK = IIK_Inherit;
-    else if (Generated && Ctor->isCopyConstructor())
-      IIK = IIK_Copy;
-    else if (Generated && Ctor->isMoveConstructor())
-      IIK = IIK_Move;
-    else
-      IIK = IIK_Default;
-  }
-
-  bool isImplicitCopyOrMove() const {
-    switch (IIK) {
-    case IIK_Copy:
-    case IIK_Move:
-      return true;
-
-    case IIK_Default:
-    case IIK_Inherit:
-      return false;
-    }
-
-    llvm_unreachable("Invalid ImplicitInitializerKind!");
-  }
-
-  bool addFieldInitializer(CXXCtorInitializer *Init) {
-    AllToInit.push_back(Init);
-
-    // Check whether this initializer makes the field "used".
-    if (Init->getInit()->HasSideEffects(S.Context))
-      S.UnusedPrivateFields.remove(Init->getAnyMember());
-
-    return false;
-  }
-
-  bool isInactiveUnionMember(FieldDecl *Field) {
-    RecordDecl *Record = Field->getParent();
-    if (!Record->isUnion())
-      return false;
-
-    if (FieldDecl *Active =
-            ActiveUnionMember.lookup(Record->getCanonicalDecl()))
-      return Active != Field->getCanonicalDecl();
-
-    // In an implicit copy or move constructor, ignore any in-class initializer.
-    if (isImplicitCopyOrMove())
-      return true;
-
-    // If there's no explicit initialization, the field is active only if it
-    // has an in-class initializer...
-    if (Field->hasInClassInitializer())
-      return false;
-    // ... or it's an anonymous struct or union whose class has an in-class
-    // initializer.
-    if (!Field->isAnonymousStructOrUnion())
-      return true;
-    CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
-    return !FieldRD->hasInClassInitializer();
-  }
-
-  /// Determine whether the given field is, or is within, a union member
-  /// that is inactive (because there was an initializer given for a different
-  /// member of the union, or because the union was not initialized at all).
-  bool isWithinInactiveUnionMember(FieldDecl *Field,
-                                   IndirectFieldDecl *Indirect) {
-    if (!Indirect)
-      return isInactiveUnionMember(Field);
-
-    for (auto *C : Indirect->chain()) {
-      FieldDecl *Field = dyn_cast<FieldDecl>(C);
-      if (Field && isInactiveUnionMember(Field))
-        return true;
-    }
-    return false;
-  }
-};
-}
-
-/// Determine whether the given type is an incomplete or zero-lenfgth
-/// array type.
-static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
-  if (T->isIncompleteArrayType())
-    return true;
-
-  while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
-    if (!ArrayT->getSize())
-      return true;
-
-    T = ArrayT->getElementType();
-  }
-
-  return false;
-}
-
-static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
-                                    FieldDecl *Field,
-                                    IndirectFieldDecl *Indirect = nullptr) {
-  if (Field->isInvalidDecl())
-    return false;
-
-  // Overwhelmingly common case: we have a direct initializer for this field.
-  if (CXXCtorInitializer *Init =
-          Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
-    return Info.addFieldInitializer(Init);
-
-  // C++11 [class.base.init]p8:
-  //   if the entity is a non-static data member that has a
-  //   brace-or-equal-initializer and either
-  //   -- the constructor's class is a union and no other variant member of that
-  //      union is designated by a mem-initializer-id or
-  //   -- the constructor's class is not a union, and, if the entity is a member
-  //      of an anonymous union, no other member of that union is designated by
-  //      a mem-initializer-id,
-  //   the entity is initialized as specified in [dcl.init].
-  //
-  // We also apply the same rules to handle anonymous structs within anonymous
-  // unions.
-  if (Info.isWithinInactiveUnionMember(Field, Indirect))
-    return false;
-
-  if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
-    ExprResult DIE =
-        SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
-    if (DIE.isInvalid())
-      return true;
-
-    auto Entity = InitializedEntity::InitializeMember(Field, nullptr, true);
-    SemaRef.checkInitializerLifetime(Entity, DIE.get());
-
-    CXXCtorInitializer *Init;
-    if (Indirect)
-      Init = new (SemaRef.Context)
-          CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
-                             SourceLocation(), DIE.get(), SourceLocation());
-    else
-      Init = new (SemaRef.Context)
-          CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
-                             SourceLocation(), DIE.get(), SourceLocation());
-    return Info.addFieldInitializer(Init);
-  }
-
-  // Don't initialize incomplete or zero-length arrays.
-  if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
-    return false;
-
-  // Don't try to build an implicit initializer if there were semantic
-  // errors in any of the initializers (and therefore we might be
-  // missing some that the user actually wrote).
-  if (Info.AnyErrorsInInits)
-    return false;
-
-  CXXCtorInitializer *Init = nullptr;
-  if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
-                                     Indirect, Init))
-    return true;
-
-  if (!Init)
-    return false;
-
-  return Info.addFieldInitializer(Init);
-}
-
-bool
-Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
-                               CXXCtorInitializer *Initializer) {
-  assert(Initializer->isDelegatingInitializer());
-  Constructor->setNumCtorInitializers(1);
-  CXXCtorInitializer **initializer =
-    new (Context) CXXCtorInitializer*[1];
-  memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
-  Constructor->setCtorInitializers(initializer);
-
-  if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
-    MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
-    DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
-  }
-
-  DelegatingCtorDecls.push_back(Constructor);
-
-  DiagnoseUninitializedFields(*this, Constructor);
-
-  return false;
-}
-
-bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
-                               ArrayRef<CXXCtorInitializer *> Initializers) {
-  if (Constructor->isDependentContext()) {
-    // Just store the initializers as written, they will be checked during
-    // instantiation.
-    if (!Initializers.empty()) {
-      Constructor->setNumCtorInitializers(Initializers.size());
-      CXXCtorInitializer **baseOrMemberInitializers =
-        new (Context) CXXCtorInitializer*[Initializers.size()];
-      memcpy(baseOrMemberInitializers, Initializers.data(),
-             Initializers.size() * sizeof(CXXCtorInitializer*));
-      Constructor->setCtorInitializers(baseOrMemberInitializers);
-    }
-
-    // Let template instantiation know whether we had errors.
-    if (AnyErrors)
-      Constructor->setInvalidDecl();
-
-    return false;
-  }
-
-  BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
-
-  // We need to build the initializer AST according to order of construction
-  // and not what user specified in the Initializers list.
-  CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
-  if (!ClassDecl)
-    return true;
-
-  bool HadError = false;
-
-  for (unsigned i = 0; i < Initializers.size(); i++) {
-    CXXCtorInitializer *Member = Initializers[i];
-
-    if (Member->isBaseInitializer())
-      Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
-    else {
-      Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
-
-      if (IndirectFieldDecl *F = Member->getIndirectMember()) {
-        for (auto *C : F->chain()) {
-          FieldDecl *FD = dyn_cast<FieldDecl>(C);
-          if (FD && FD->getParent()->isUnion())
-            Info.ActiveUnionMember.insert(std::make_pair(
-                FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
-        }
-      } else if (FieldDecl *FD = Member->getMember()) {
-        if (FD->getParent()->isUnion())
-          Info.ActiveUnionMember.insert(std::make_pair(
-              FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
-      }
-    }
-  }
-
-  // Keep track of the direct virtual bases.
-  llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
-  for (auto &I : ClassDecl->bases()) {
-    if (I.isVirtual())
-      DirectVBases.insert(&I);
-  }
-
-  // Push virtual bases before others.
-  for (auto &VBase : ClassDecl->vbases()) {
-    if (CXXCtorInitializer *Value
-        = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
-      // [class.base.init]p7, per DR257:
-      //   A mem-initializer where the mem-initializer-id names a virtual base
-      //   class is ignored during execution of a constructor of any class that
-      //   is not the most derived class.
-      if (ClassDecl->isAbstract()) {
-        // FIXME: Provide a fixit to remove the base specifier. This requires
-        // tracking the location of the associated comma for a base specifier.
-        Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
-          << VBase.getType() << ClassDecl;
-        DiagnoseAbstractType(ClassDecl);
-      }
-
-      Info.AllToInit.push_back(Value);
-    } else if (!AnyErrors && !ClassDecl->isAbstract()) {
-      // [class.base.init]p8, per DR257:
-      //   If a given [...] base class is not named by a mem-initializer-id
-      //   [...] and the entity is not a virtual base class of an abstract
-      //   class, then [...] the entity is default-initialized.
-      bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
-      CXXCtorInitializer *CXXBaseInit;
-      if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
-                                       &VBase, IsInheritedVirtualBase,
-                                       CXXBaseInit)) {
-        HadError = true;
-        continue;
-      }
-
-      Info.AllToInit.push_back(CXXBaseInit);
-    }
-  }
-
-  // Non-virtual bases.
-  for (auto &Base : ClassDecl->bases()) {
-    // Virtuals are in the virtual base list and already constructed.
-    if (Base.isVirtual())
-      continue;
-
-    if (CXXCtorInitializer *Value
-          = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
-      Info.AllToInit.push_back(Value);
-    } else if (!AnyErrors) {
-      CXXCtorInitializer *CXXBaseInit;
-      if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
-                                       &Base, /*IsInheritedVirtualBase=*/false,
-                                       CXXBaseInit)) {
-        HadError = true;
-        continue;
-      }
-
-      Info.AllToInit.push_back(CXXBaseInit);
-    }
-  }
-
-  // Fields.
-  for (auto *Mem : ClassDecl->decls()) {
-    if (auto *F = dyn_cast<FieldDecl>(Mem)) {
-      // C++ [class.bit]p2:
-      //   A declaration for a bit-field that omits the identifier declares an
-      //   unnamed bit-field. Unnamed bit-fields are not members and cannot be
-      //   initialized.
-      if (F->isUnnamedBitfield())
-        continue;
-
-      // If we're not generating the implicit copy/move constructor, then we'll
-      // handle anonymous struct/union fields based on their individual
-      // indirect fields.
-      if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
-        continue;
-
-      if (CollectFieldInitializer(*this, Info, F))
-        HadError = true;
-      continue;
-    }
-
-    // Beyond this point, we only consider default initialization.
-    if (Info.isImplicitCopyOrMove())
-      continue;
-
-    if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
-      if (F->getType()->isIncompleteArrayType()) {
-        assert(ClassDecl->hasFlexibleArrayMember() &&
-               "Incomplete array type is not valid");
-        continue;
-      }
-
-      // Initialize each field of an anonymous struct individually.
-      if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
-        HadError = true;
-
-      continue;
-    }
-  }
-
-  unsigned NumInitializers = Info.AllToInit.size();
-  if (NumInitializers > 0) {
-    Constructor->setNumCtorInitializers(NumInitializers);
-    CXXCtorInitializer **baseOrMemberInitializers =
-      new (Context) CXXCtorInitializer*[NumInitializers];
-    memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
-           NumInitializers * sizeof(CXXCtorInitializer*));
-    Constructor->setCtorInitializers(baseOrMemberInitializers);
-
-    // Constructors implicitly reference the base and member
-    // destructors.
-    MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
-                                           Constructor->getParent());
-  }
-
-  return HadError;
-}
-
-static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
-  if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
-    const RecordDecl *RD = RT->getDecl();
-    if (RD->isAnonymousStructOrUnion()) {
-      for (auto *Field : RD->fields())
-        PopulateKeysForFields(Field, IdealInits);
-      return;
-    }
-  }
-  IdealInits.push_back(Field->getCanonicalDecl());
-}
-
-static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
-  return Context.getCanonicalType(BaseType).getTypePtr();
-}
-
-static const void *GetKeyForMember(ASTContext &Context,
-                                   CXXCtorInitializer *Member) {
-  if (!Member->isAnyMemberInitializer())
-    return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
-
-  return Member->getAnyMember()->getCanonicalDecl();
-}
-
-static void DiagnoseBaseOrMemInitializerOrder(
-    Sema &SemaRef, const CXXConstructorDecl *Constructor,
-    ArrayRef<CXXCtorInitializer *> Inits) {
-  if (Constructor->getDeclContext()->isDependentContext())
-    return;
-
-  // Don't check initializers order unless the warning is enabled at the
-  // location of at least one initializer.
-  bool ShouldCheckOrder = false;
-  for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
-    CXXCtorInitializer *Init = Inits[InitIndex];
-    if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
-                                 Init->getSourceLocation())) {
-      ShouldCheckOrder = true;
-      break;
-    }
-  }
-  if (!ShouldCheckOrder)
-    return;
-
-  // Build the list of bases and members in the order that they'll
-  // actually be initialized.  The explicit initializers should be in
-  // this same order but may be missing things.
-  SmallVector<const void*, 32> IdealInitKeys;
-
-  const CXXRecordDecl *ClassDecl = Constructor->getParent();
-
-  // 1. Virtual bases.
-  for (const auto &VBase : ClassDecl->vbases())
-    IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
-
-  // 2. Non-virtual bases.
-  for (const auto &Base : ClassDecl->bases()) {
-    if (Base.isVirtual())
-      continue;
-    IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
-  }
-
-  // 3. Direct fields.
-  for (auto *Field : ClassDecl->fields()) {
-    if (Field->isUnnamedBitfield())
-      continue;
-
-    PopulateKeysForFields(Field, IdealInitKeys);
-  }
-
-  unsigned NumIdealInits = IdealInitKeys.size();
-  unsigned IdealIndex = 0;
-
-  CXXCtorInitializer *PrevInit = nullptr;
-  for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
-    CXXCtorInitializer *Init = Inits[InitIndex];
-    const void *InitKey = GetKeyForMember(SemaRef.Context, Init);
-
-    // Scan forward to try to find this initializer in the idealized
-    // initializers list.
-    for (; IdealIndex != NumIdealInits; ++IdealIndex)
-      if (InitKey == IdealInitKeys[IdealIndex])
-        break;
-
-    // If we didn't find this initializer, it must be because we
-    // scanned past it on a previous iteration.  That can only
-    // happen if we're out of order;  emit a warning.
-    if (IdealIndex == NumIdealInits && PrevInit) {
-      Sema::SemaDiagnosticBuilder D =
-        SemaRef.Diag(PrevInit->getSourceLocation(),
-                     diag::warn_initializer_out_of_order);
-
-      if (PrevInit->isAnyMemberInitializer())
-        D << 0 << PrevInit->getAnyMember()->getDeclName();
-      else
-        D << 1 << PrevInit->getTypeSourceInfo()->getType();
-
-      if (Init->isAnyMemberInitializer())
-        D << 0 << Init->getAnyMember()->getDeclName();
-      else
-        D << 1 << Init->getTypeSourceInfo()->getType();
-
-      // Move back to the initializer's location in the ideal list.
-      for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
-        if (InitKey == IdealInitKeys[IdealIndex])
-          break;
-
-      assert(IdealIndex < NumIdealInits &&
-             "initializer not found in initializer list");
-    }
-
-    PrevInit = Init;
-  }
-}
-
-namespace {
-bool CheckRedundantInit(Sema &S,
-                        CXXCtorInitializer *Init,
-                        CXXCtorInitializer *&PrevInit) {
-  if (!PrevInit) {
-    PrevInit = Init;
-    return false;
-  }
-
-  if (FieldDecl *Field = Init->getAnyMember())
-    S.Diag(Init->getSourceLocation(),
-           diag::err_multiple_mem_initialization)
-      << Field->getDeclName()
-      << Init->getSourceRange();
-  else {
-    const Type *BaseClass = Init->getBaseClass();
-    assert(BaseClass && "neither field nor base");
-    S.Diag(Init->getSourceLocation(),
-           diag::err_multiple_base_initialization)
-      << QualType(BaseClass, 0)
-      << Init->getSourceRange();
-  }
-  S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
-    << 0 << PrevInit->getSourceRange();
-
-  return true;
-}
-
-typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
-typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
-
-bool CheckRedundantUnionInit(Sema &S,
-                             CXXCtorInitializer *Init,
-                             RedundantUnionMap &Unions) {
-  FieldDecl *Field = Init->getAnyMember();
-  RecordDecl *Parent = Field->getParent();
-  NamedDecl *Child = Field;
-
-  while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
-    if (Parent->isUnion()) {
-      UnionEntry &En = Unions[Parent];
-      if (En.first && En.first != Child) {
-        S.Diag(Init->getSourceLocation(),
-               diag::err_multiple_mem_union_initialization)
-          << Field->getDeclName()
-          << Init->getSourceRange();
-        S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
-          << 0 << En.second->getSourceRange();
-        return true;
-      }
-      if (!En.first) {
-        En.first = Child;
-        En.second = Init;
-      }
-      if (!Parent->isAnonymousStructOrUnion())
-        return false;
-    }
-
-    Child = Parent;
-    Parent = cast<RecordDecl>(Parent->getDeclContext());
-  }
-
-  return false;
-}
-}
-
-/// ActOnMemInitializers - Handle the member initializers for a constructor.
-void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
-                                SourceLocation ColonLoc,
-                                ArrayRef<CXXCtorInitializer*> MemInits,
-                                bool AnyErrors) {
-  if (!ConstructorDecl)
-    return;
-
-  AdjustDeclIfTemplate(ConstructorDecl);
-
-  CXXConstructorDecl *Constructor
-    = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
-
-  if (!Constructor) {
-    Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
-    return;
-  }
-
-  // Mapping for the duplicate initializers check.
-  // For member initializers, this is keyed with a FieldDecl*.
-  // For base initializers, this is keyed with a Type*.
-  llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
-
-  // Mapping for the inconsistent anonymous-union initializers check.
-  RedundantUnionMap MemberUnions;
-
-  bool HadError = false;
-  for (unsigned i = 0; i < MemInits.size(); i++) {
-    CXXCtorInitializer *Init = MemInits[i];
-
-    // Set the source order index.
-    Init->setSourceOrder(i);
-
-    if (Init->isAnyMemberInitializer()) {
-      const void *Key = GetKeyForMember(Context, Init);
-      if (CheckRedundantInit(*this, Init, Members[Key]) ||
-          CheckRedundantUnionInit(*this, Init, MemberUnions))
-        HadError = true;
-    } else if (Init->isBaseInitializer()) {
-      const void *Key = GetKeyForMember(Context, Init);
-      if (CheckRedundantInit(*this, Init, Members[Key]))
-        HadError = true;
-    } else {
-      assert(Init->isDelegatingInitializer());
-      // This must be the only initializer
-      if (MemInits.size() != 1) {
-        Diag(Init->getSourceLocation(),
-             diag::err_delegating_initializer_alone)
-          << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
-        // We will treat this as being the only initializer.
-      }
-      SetDelegatingInitializer(Constructor, MemInits[i]);
-      // Return immediately as the initializer is set.
-      return;
-    }
-  }
-
-  if (HadError)
-    return;
-
-  DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
-
-  SetCtorInitializers(Constructor, AnyErrors, MemInits);
-
-  DiagnoseUninitializedFields(*this, Constructor);
-}
-
-void
-Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
-                                             CXXRecordDecl *ClassDecl) {
-  // Ignore dependent contexts. Also ignore unions, since their members never
-  // have destructors implicitly called.
-  if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
-    return;
-
-  // FIXME: all the access-control diagnostics are positioned on the
-  // field/base declaration.  That's probably good; that said, the
-  // user might reasonably want to know why the destructor is being
-  // emitted, and we currently don't say.
-
-  // Non-static data members.
-  for (auto *Field : ClassDecl->fields()) {
-    if (Field->isInvalidDecl())
-      continue;
-
-    // Don't destroy incomplete or zero-length arrays.
-    if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
-      continue;
-
-    QualType FieldType = Context.getBaseElementType(Field->getType());
-
-    const RecordType* RT = FieldType->getAs<RecordType>();
-    if (!RT)
-      continue;
-
-    CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
-    if (FieldClassDecl->isInvalidDecl())
-      continue;
-    if (FieldClassDecl->hasIrrelevantDestructor())
-      continue;
-    // The destructor for an implicit anonymous union member is never invoked.
-    if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
-      continue;
-
-    CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
-    assert(Dtor && "No dtor found for FieldClassDecl!");
-    CheckDestructorAccess(Field->getLocation(), Dtor,
-                          PDiag(diag::err_access_dtor_field)
-                            << Field->getDeclName()
-                            << FieldType);
-
-    MarkFunctionReferenced(Location, Dtor);
-    DiagnoseUseOfDecl(Dtor, Location);
-  }
-
-  // We only potentially invoke the destructors of potentially constructed
-  // subobjects.
-  bool VisitVirtualBases = !ClassDecl->isAbstract();
-
-  llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
-
-  // Bases.
-  for (const auto &Base : ClassDecl->bases()) {
-    // Bases are always records in a well-formed non-dependent class.
-    const RecordType *RT = Base.getType()->getAs<RecordType>();
-
-    // Remember direct virtual bases.
-    if (Base.isVirtual()) {
-      if (!VisitVirtualBases)
-        continue;
-      DirectVirtualBases.insert(RT);
-    }
-
-    CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
-    // If our base class is invalid, we probably can't get its dtor anyway.
-    if (BaseClassDecl->isInvalidDecl())
-      continue;
-    if (BaseClassDecl->hasIrrelevantDestructor())
-      continue;
-
-    CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
-    assert(Dtor && "No dtor found for BaseClassDecl!");
-
-    // FIXME: caret should be on the start of the class name
-    CheckDestructorAccess(Base.getBeginLoc(), Dtor,
-                          PDiag(diag::err_access_dtor_base)
-                              << Base.getType() << Base.getSourceRange(),
-                          Context.getTypeDeclType(ClassDecl));
-
-    MarkFunctionReferenced(Location, Dtor);
-    DiagnoseUseOfDecl(Dtor, Location);
-  }
-
-  if (!VisitVirtualBases)
-    return;
-
-  // Virtual bases.
-  for (const auto &VBase : ClassDecl->vbases()) {
-    // Bases are always records in a well-formed non-dependent class.
-    const RecordType *RT = VBase.getType()->castAs<RecordType>();
-
-    // Ignore direct virtual bases.
-    if (DirectVirtualBases.count(RT))
-      continue;
-
-    CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
-    // If our base class is invalid, we probably can't get its dtor anyway.
-    if (BaseClassDecl->isInvalidDecl())
-      continue;
-    if (BaseClassDecl->hasIrrelevantDestructor())
-      continue;
-
-    CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
-    assert(Dtor && "No dtor found for BaseClassDecl!");
-    if (CheckDestructorAccess(
-            ClassDecl->getLocation(), Dtor,
-            PDiag(diag::err_access_dtor_vbase)
-                << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
-            Context.getTypeDeclType(ClassDecl)) ==
-        AR_accessible) {
-      CheckDerivedToBaseConversion(
-          Context.getTypeDeclType(ClassDecl), VBase.getType(),
-          diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
-          SourceRange(), DeclarationName(), nullptr);
-    }
-
-    MarkFunctionReferenced(Location, Dtor);
-    DiagnoseUseOfDecl(Dtor, Location);
-  }
-}
-
-void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
-  if (!CDtorDecl)
-    return;
-
-  if (CXXConstructorDecl *Constructor
-      = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
-    SetCtorInitializers(Constructor, /*AnyErrors=*/false);
-    DiagnoseUninitializedFields(*this, Constructor);
-  }
-}
-
-bool Sema::isAbstractType(SourceLocation Loc, QualType T) {
-  if (!getLangOpts().CPlusPlus)
-    return false;
-
-  const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
-  if (!RD)
-    return false;
-
-  // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
-  // class template specialization here, but doing so breaks a lot of code.
-
-  // We can't answer whether something is abstract until it has a
-  // definition. If it's currently being defined, we'll walk back
-  // over all the declarations when we have a full definition.
-  const CXXRecordDecl *Def = RD->getDefinition();
-  if (!Def || Def->isBeingDefined())
-    return false;
-
-  return RD->isAbstract();
-}
-
-bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
-                                  TypeDiagnoser &Diagnoser) {
-  if (!isAbstractType(Loc, T))
-    return false;
-
-  T = Context.getBaseElementType(T);
-  Diagnoser.diagnose(*this, Loc, T);
-  DiagnoseAbstractType(T->getAsCXXRecordDecl());
-  return true;
-}
-
-void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
-  // Check if we've already emitted the list of pure virtual functions
-  // for this class.
-  if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
-    return;
-
-  // If the diagnostic is suppressed, don't emit the notes. We're only
-  // going to emit them once, so try to attach them to a diagnostic we're
-  // actually going to show.
-  if (Diags.isLastDiagnosticIgnored())
-    return;
-
-  CXXFinalOverriderMap FinalOverriders;
-  RD->getFinalOverriders(FinalOverriders);
-
-  // Keep a set of seen pure methods so we won't diagnose the same method
-  // more than once.
-  llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
-
-  for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
-                                   MEnd = FinalOverriders.end();
-       M != MEnd;
-       ++M) {
-    for (OverridingMethods::iterator SO = M->second.begin(),
-                                  SOEnd = M->second.end();
-         SO != SOEnd; ++SO) {
-      // C++ [class.abstract]p4:
-      //   A class is abstract if it contains or inherits at least one
-      //   pure virtual function for which the final overrider is pure
-      //   virtual.
-
-      //
-      if (SO->second.size() != 1)
-        continue;
-
-      if (!SO->second.front().Method->isPure())
-        continue;
-
-      if (!SeenPureMethods.insert(SO->second.front().Method).second)
-        continue;
-
-      Diag(SO->second.front().Method->getLocation(),
-           diag::note_pure_virtual_function)
-        << SO->second.front().Method->getDeclName() << RD->getDeclName();
-    }
-  }
-
-  if (!PureVirtualClassDiagSet)
-    PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
-  PureVirtualClassDiagSet->insert(RD);
-}
-
-namespace {
-struct AbstractUsageInfo {
-  Sema &S;
-  CXXRecordDecl *Record;
-  CanQualType AbstractType;
-  bool Invalid;
-
-  AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
-    : S(S), Record(Record),
-      AbstractType(S.Context.getCanonicalType(
-                   S.Context.getTypeDeclType(Record))),
-      Invalid(false) {}
-
-  void DiagnoseAbstractType() {
-    if (Invalid) return;
-    S.DiagnoseAbstractType(Record);
-    Invalid = true;
-  }
-
-  void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
-};
-
-struct CheckAbstractUsage {
-  AbstractUsageInfo &Info;
-  const NamedDecl *Ctx;
-
-  CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
-    : Info(Info), Ctx(Ctx) {}
-
-  void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
-    switch (TL.getTypeLocClass()) {
-#define ABSTRACT_TYPELOC(CLASS, PARENT)
-#define TYPELOC(CLASS, PARENT) \
-    case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
-#include "clang/AST/TypeLocNodes.def"
-    }
-  }
-
-  void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
-    Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
-    for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
-      if (!TL.getParam(I))
-        continue;
-
-      TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
-      if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
-    }
-  }
-
-  void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
-    Visit(TL.getElementLoc(), Sema::AbstractArrayType);
-  }
-
-  void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
-    // Visit the type parameters from a permissive context.
-    for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
-      TemplateArgumentLoc TAL = TL.getArgLoc(I);
-      if (TAL.getArgument().getKind() == TemplateArgument::Type)
-        if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
-          Visit(TSI->getTypeLoc(), Sema::AbstractNone);
-      // TODO: other template argument types?
-    }
-  }
-
-  // Visit pointee types from a permissive context.
-#define CheckPolymorphic(Type) \
-  void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
-    Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
-  }
-  CheckPolymorphic(PointerTypeLoc)
-  CheckPolymorphic(ReferenceTypeLoc)
-  CheckPolymorphic(MemberPointerTypeLoc)
-  CheckPolymorphic(BlockPointerTypeLoc)
-  CheckPolymorphic(AtomicTypeLoc)
-
-  /// Handle all the types we haven't given a more specific
-  /// implementation for above.
-  void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
-    // Every other kind of type that we haven't called out already
-    // that has an inner type is either (1) sugar or (2) contains that
-    // inner type in some way as a subobject.
-    if (TypeLoc Next = TL.getNextTypeLoc())
-      return Visit(Next, Sel);
-
-    // If there's no inner type and we're in a permissive context,
-    // don't diagnose.
-    if (Sel == Sema::AbstractNone) return;
-
-    // Check whether the type matches the abstract type.
-    QualType T = TL.getType();
-    if (T->isArrayType()) {
-      Sel = Sema::AbstractArrayType;
-      T = Info.S.Context.getBaseElementType(T);
-    }
-    CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
-    if (CT != Info.AbstractType) return;
-
-    // It matched; do some magic.
-    if (Sel == Sema::AbstractArrayType) {
-      Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
-        << T << TL.getSourceRange();
-    } else {
-      Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
-        << Sel << T << TL.getSourceRange();
-    }
-    Info.DiagnoseAbstractType();
-  }
-};
-
-void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
-                                  Sema::AbstractDiagSelID Sel) {
-  CheckAbstractUsage(*this, D).Visit(TL, Sel);
-}
-
-}
-
-/// Check for invalid uses of an abstract type in a method declaration.
-static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
-                                    CXXMethodDecl *MD) {
-  // No need to do the check on definitions, which require that
-  // the return/param types be complete.
-  if (MD->doesThisDeclarationHaveABody())
-    return;
-
-  // For safety's sake, just ignore it if we don't have type source
-  // information.  This should never happen for non-implicit methods,
-  // but...
-  if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
-    Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone);
-}
-
-/// Check for invalid uses of an abstract type within a class definition.
-static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
-                                    CXXRecordDecl *RD) {
-  for (auto *D : RD->decls()) {
-    if (D->isImplicit()) continue;
-
-    // Methods and method templates.
-    if (isa<CXXMethodDecl>(D)) {
-      CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D));
-    } else if (isa<FunctionTemplateDecl>(D)) {
-      FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl();
-      CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD));
-
-    // Fields and static variables.
-    } else if (isa<FieldDecl>(D)) {
-      FieldDecl *FD = cast<FieldDecl>(D);
-      if (TypeSourceInfo *TSI = FD->getTypeSourceInfo())
-        Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType);
-    } else if (isa<VarDecl>(D)) {
-      VarDecl *VD = cast<VarDecl>(D);
-      if (TypeSourceInfo *TSI = VD->getTypeSourceInfo())
-        Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType);
-
-    // Nested classes and class templates.
-    } else if (isa<CXXRecordDecl>(D)) {
-      CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D));
-    } else if (isa<ClassTemplateDecl>(D)) {
-      CheckAbstractClassUsage(Info,
-                             cast<ClassTemplateDecl>(D)->getTemplatedDecl());
-    }
-  }
-}
-
-static void ReferenceDllExportedMembers(Sema &S, CXXRecordDecl *Class) {
-  Attr *ClassAttr = getDLLAttr(Class);
-  if (!ClassAttr)
-    return;
-
-  assert(ClassAttr->getKind() == attr::DLLExport);
-
-  TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
-
-  if (TSK == TSK_ExplicitInstantiationDeclaration)
-    // Don't go any further if this is just an explicit instantiation
-    // declaration.
-    return;
-
-  if (S.Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
-    S.MarkVTableUsed(Class->getLocation(), Class, true);
-
-  for (Decl *Member : Class->decls()) {
-    // Defined static variables that are members of an exported base
-    // class must be marked export too.
-    auto *VD = dyn_cast<VarDecl>(Member);
-    if (VD && Member->getAttr<DLLExportAttr>() &&
-        VD->getStorageClass() == SC_Static &&
-        TSK == TSK_ImplicitInstantiation)
-      S.MarkVariableReferenced(VD->getLocation(), VD);
-
-    auto *MD = dyn_cast<CXXMethodDecl>(Member);
-    if (!MD)
-      continue;
-
-    if (Member->getAttr<DLLExportAttr>()) {
-      if (MD->isUserProvided()) {
-        // Instantiate non-default class member functions ...
-
-        // .. except for certain kinds of template specializations.
-        if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
-          continue;
-
-        S.MarkFunctionReferenced(Class->getLocation(), MD);
-
-        // The function will be passed to the consumer when its definition is
-        // encountered.
-      } else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
-                 MD->isCopyAssignmentOperator() ||
-                 MD->isMoveAssignmentOperator()) {
-        // Synthesize and instantiate non-trivial implicit methods, explicitly
-        // defaulted methods, and the copy and move assignment operators. The
-        // latter are exported even if they are trivial, because the address of
-        // an operator can be taken and should compare equal across libraries.
-        DiagnosticErrorTrap Trap(S.Diags);
-        S.MarkFunctionReferenced(Class->getLocation(), MD);
-        if (Trap.hasErrorOccurred()) {
-          S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
-              << Class << !S.getLangOpts().CPlusPlus11;
-          break;
-        }
-
-        // There is no later point when we will see the definition of this
-        // function, so pass it to the consumer now.
-        S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
-      }
-    }
-  }
-}
-
-static void checkForMultipleExportedDefaultConstructors(Sema &S,
-                                                        CXXRecordDecl *Class) {
-  // Only the MS ABI has default constructor closures, so we don't need to do
-  // this semantic checking anywhere else.
-  if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
-    return;
-
-  CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
-  for (Decl *Member : Class->decls()) {
-    // Look for exported default constructors.
-    auto *CD = dyn_cast<CXXConstructorDecl>(Member);
-    if (!CD || !CD->isDefaultConstructor())
-      continue;
-    auto *Attr = CD->getAttr<DLLExportAttr>();
-    if (!Attr)
-      continue;
-
-    // If the class is non-dependent, mark the default arguments as ODR-used so
-    // that we can properly codegen the constructor closure.
-    if (!Class->isDependentContext()) {
-      for (ParmVarDecl *PD : CD->parameters()) {
-        (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
-        S.DiscardCleanupsInEvaluationContext();
-      }
-    }
-
-    if (LastExportedDefaultCtor) {
-      S.Diag(LastExportedDefaultCtor->getLocation(),
-             diag::err_attribute_dll_ambiguous_default_ctor)
-          << Class;
-      S.Diag(CD->getLocation(), diag::note_entity_declared_at)
-          << CD->getDeclName();
-      return;
-    }
-    LastExportedDefaultCtor = CD;
-  }
-}
-
-void Sema::checkClassLevelCodeSegAttribute(CXXRecordDecl *Class) {
-  // Mark any compiler-generated routines with the implicit code_seg attribute.
-  for (auto *Method : Class->methods()) {
-    if (Method->isUserProvided())
-      continue;
-    if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true))
-      Method->addAttr(A);
-  }
-}
-
-/// Check class-level dllimport/dllexport attribute.
-void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
-  Attr *ClassAttr = getDLLAttr(Class);
-
-  // MSVC inherits DLL attributes to partial class template specializations.
-  if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
-    if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
-      if (Attr *TemplateAttr =
-              getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
-        auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
-        A->setInherited(true);
-        ClassAttr = A;
-      }
-    }
-  }
-
-  if (!ClassAttr)
-    return;
-
-  if (!Class->isExternallyVisible()) {
-    Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
-        << Class << ClassAttr;
-    return;
-  }
-
-  if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
-      !ClassAttr->isInherited()) {
-    // Diagnose dll attributes on members of class with dll attribute.
-    for (Decl *Member : Class->decls()) {
-      if (!isa<VarDecl>(Member) && !isa<CXXMethodDecl>(Member))
-        continue;
-      InheritableAttr *MemberAttr = getDLLAttr(Member);
-      if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
-        continue;
-
-      Diag(MemberAttr->getLocation(),
-             diag::err_attribute_dll_member_of_dll_class)
-          << MemberAttr << ClassAttr;
-      Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
-      Member->setInvalidDecl();
-    }
-  }
-
-  if (Class->getDescribedClassTemplate())
-    // Don't inherit dll attribute until the template is instantiated.
-    return;
-
-  // The class is either imported or exported.
-  const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
-
-  // Check if this was a dllimport attribute propagated from a derived class to
-  // a base class template specialization. We don't apply these attributes to
-  // static data members.
-  const bool PropagatedImport =
-      !ClassExported &&
-      cast<DLLImportAttr>(ClassAttr)->wasPropagatedToBaseTemplate();
-
-  TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
-
-  // Ignore explicit dllexport on explicit class template instantiation declarations.
-  if (ClassExported && !ClassAttr->isInherited() &&
-      TSK == TSK_ExplicitInstantiationDeclaration) {
-    Class->dropAttr<DLLExportAttr>();
-    return;
-  }
-
-  // Force declaration of implicit members so they can inherit the attribute.
-  ForceDeclarationOfImplicitMembers(Class);
-
-  // FIXME: MSVC's docs say all bases must be exportable, but this doesn't
-  // seem to be true in practice?
-
-  for (Decl *Member : Class->decls()) {
-    VarDecl *VD = dyn_cast<VarDecl>(Member);
-    CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member);
-
-    // Only methods and static fields inherit the attributes.
-    if (!VD && !MD)
-      continue;
-
-    if (MD) {
-      // Don't process deleted methods.
-      if (MD->isDeleted())
-        continue;
-
-      if (MD->isInlined()) {
-        // MinGW does not import or export inline methods.
-        if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
-            !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment())
-          continue;
-
-        // MSVC versions before 2015 don't export the move assignment operators
-        // and move constructor, so don't attempt to import/export them if
-        // we have a definition.
-        auto *Ctor = dyn_cast<CXXConstructorDecl>(MD);
-        if ((MD->isMoveAssignmentOperator() ||
-             (Ctor && Ctor->isMoveConstructor())) &&
-            !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
-          continue;
-
-        // MSVC2015 doesn't export trivial defaulted x-tor but copy assign
-        // operator is exported anyway.
-        if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
-            (Ctor || isa<CXXDestructorDecl>(MD)) && MD->isTrivial())
-          continue;
-      }
-    }
-
-    // Don't apply dllimport attributes to static data members of class template
-    // instantiations when the attribute is propagated from a derived class.
-    if (VD && PropagatedImport)
-      continue;
-
-    if (!cast<NamedDecl>(Member)->isExternallyVisible())
-      continue;
-
-    if (!getDLLAttr(Member)) {
-      InheritableAttr *NewAttr = nullptr;
-
-      // Do not export/import inline function when -fno-dllexport-inlines is
-      // passed. But add attribute for later local static var check.
-      if (!getLangOpts().DllExportInlines && MD && MD->isInlined() &&
-          TSK != TSK_ExplicitInstantiationDeclaration &&
-          TSK != TSK_ExplicitInstantiationDefinition) {
-        if (ClassExported) {
-          NewAttr = ::new (getASTContext())
-            DLLExportStaticLocalAttr(ClassAttr->getRange(),
-                                     getASTContext(),
-                                     ClassAttr->getSpellingListIndex());
-        } else {
-          NewAttr = ::new (getASTContext())
-            DLLImportStaticLocalAttr(ClassAttr->getRange(),
-                                     getASTContext(),
-                                     ClassAttr->getSpellingListIndex());
-        }
-      } else {
-        NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
-      }
-
-      NewAttr->setInherited(true);
-      Member->addAttr(NewAttr);
-
-      if (MD) {
-        // Propagate DLLAttr to friend re-declarations of MD that have already
-        // been constructed.
-        for (FunctionDecl *FD = MD->getMostRecentDecl(); FD;
-             FD = FD->getPreviousDecl()) {
-          if (FD->getFriendObjectKind() == Decl::FOK_None)
-            continue;
-          assert(!getDLLAttr(FD) &&
-                 "friend re-decl should not already have a DLLAttr");
-          NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
-          NewAttr->setInherited(true);
-          FD->addAttr(NewAttr);
-        }
-      }
-    }
-  }
-
-  if (ClassExported)
-    DelayedDllExportClasses.push_back(Class);
-}
-
-/// Perform propagation of DLL attributes from a derived class to a
-/// templated base class for MS compatibility.
-void Sema::propagateDLLAttrToBaseClassTemplate(
-    CXXRecordDecl *Class, Attr *ClassAttr,
-    ClassTemplateSpecializationDecl *BaseTemplateSpec, SourceLocation BaseLoc) {
-  if (getDLLAttr(
-          BaseTemplateSpec->getSpecializedTemplate()->getTemplatedDecl())) {
-    // If the base class template has a DLL attribute, don't try to change it.
-    return;
-  }
-
-  auto TSK = BaseTemplateSpec->getSpecializationKind();
-  if (!getDLLAttr(BaseTemplateSpec) &&
-      (TSK == TSK_Undeclared || TSK == TSK_ExplicitInstantiationDeclaration ||
-       TSK == TSK_ImplicitInstantiation)) {
-    // The template hasn't been instantiated yet (or it has, but only as an
-    // explicit instantiation declaration or implicit instantiation, which means
-    // we haven't codegenned any members yet), so propagate the attribute.
-    auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
-    NewAttr->setInherited(true);
-    BaseTemplateSpec->addAttr(NewAttr);
-
-    // If this was an import, mark that we propagated it from a derived class to
-    // a base class template specialization.
-    if (auto *ImportAttr = dyn_cast<DLLImportAttr>(NewAttr))
-      ImportAttr->setPropagatedToBaseTemplate();
-
-    // If the template is already instantiated, checkDLLAttributeRedeclaration()
-    // needs to be run again to work see the new attribute. Otherwise this will
-    // get run whenever the template is instantiated.
-    if (TSK != TSK_Undeclared)
-      checkClassLevelDLLAttribute(BaseTemplateSpec);
-
-    return;
-  }
-
-  if (getDLLAttr(BaseTemplateSpec)) {
-    // The template has already been specialized or instantiated with an
-    // attribute, explicitly or through propagation. We should not try to change
-    // it.
-    return;
-  }
-
-  // The template was previously instantiated or explicitly specialized without
-  // a dll attribute, It's too late for us to add an attribute, so warn that
-  // this is unsupported.
-  Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
-      << BaseTemplateSpec->isExplicitSpecialization();
-  Diag(ClassAttr->getLocation(), diag::note_attribute);
-  if (BaseTemplateSpec->isExplicitSpecialization()) {
-    Diag(BaseTemplateSpec->getLocation(),
-           diag::note_template_class_explicit_specialization_was_here)
-        << BaseTemplateSpec;
-  } else {
-    Diag(BaseTemplateSpec->getPointOfInstantiation(),
-           diag::note_template_class_instantiation_was_here)
-        << BaseTemplateSpec;
-  }
-}
-
-static void DefineImplicitSpecialMember(Sema &S, CXXMethodDecl *MD,
-                                        SourceLocation DefaultLoc) {
-  switch (S.getSpecialMember(MD)) {
-  case Sema::CXXDefaultConstructor:
-    S.DefineImplicitDefaultConstructor(DefaultLoc,
-                                       cast<CXXConstructorDecl>(MD));
-    break;
-  case Sema::CXXCopyConstructor:
-    S.DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
-    break;
-  case Sema::CXXCopyAssignment:
-    S.DefineImplicitCopyAssignment(DefaultLoc, MD);
-    break;
-  case Sema::CXXDestructor:
-    S.DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
-    break;
-  case Sema::CXXMoveConstructor:
-    S.DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
-    break;
-  case Sema::CXXMoveAssignment:
-    S.DefineImplicitMoveAssignment(DefaultLoc, MD);
-    break;
-  case Sema::CXXInvalid:
-    llvm_unreachable("Invalid special member.");
-  }
-}
-
-/// Determine whether a type is permitted to be passed or returned in
-/// registers, per C++ [class.temporary]p3.
-static bool canPassInRegisters(Sema &S, CXXRecordDecl *D,
-                               TargetInfo::CallingConvKind CCK) {
-  if (D->isDependentType() || D->isInvalidDecl())
-    return false;
-
-  // Clang <= 4 used the pre-C++11 rule, which ignores move operations.
-  // The PS4 platform ABI follows the behavior of Clang 3.2.
-  if (CCK == TargetInfo::CCK_ClangABI4OrPS4)
-    return !D->hasNonTrivialDestructorForCall() &&
-           !D->hasNonTrivialCopyConstructorForCall();
-
-  if (CCK == TargetInfo::CCK_MicrosoftWin64) {
-    bool CopyCtorIsTrivial = false, CopyCtorIsTrivialForCall = false;
-    bool DtorIsTrivialForCall = false;
-
-    // If a class has at least one non-deleted, trivial copy constructor, it
-    // is passed according to the C ABI. Otherwise, it is passed indirectly.
-    //
-    // Note: This permits classes with non-trivial copy or move ctors to be
-    // passed in registers, so long as they *also* have a trivial copy ctor,
-    // which is non-conforming.
-    if (D->needsImplicitCopyConstructor()) {
-      if (!D->defaultedCopyConstructorIsDeleted()) {
-        if (D->hasTrivialCopyConstructor())
-          CopyCtorIsTrivial = true;
-        if (D->hasTrivialCopyConstructorForCall())
-          CopyCtorIsTrivialForCall = true;
-      }
-    } else {
-      for (const CXXConstructorDecl *CD : D->ctors()) {
-        if (CD->isCopyConstructor() && !CD->isDeleted()) {
-          if (CD->isTrivial())
-            CopyCtorIsTrivial = true;
-          if (CD->isTrivialForCall())
-            CopyCtorIsTrivialForCall = true;
-        }
-      }
-    }
-
-    if (D->needsImplicitDestructor()) {
-      if (!D->defaultedDestructorIsDeleted() &&
-          D->hasTrivialDestructorForCall())
-        DtorIsTrivialForCall = true;
-    } else if (const auto *DD = D->getDestructor()) {
-      if (!DD->isDeleted() && DD->isTrivialForCall())
-        DtorIsTrivialForCall = true;
-    }
-
-    // If the copy ctor and dtor are both trivial-for-calls, pass direct.
-    if (CopyCtorIsTrivialForCall && DtorIsTrivialForCall)
-      return true;
-
-    // If a class has a destructor, we'd really like to pass it indirectly
-    // because it allows us to elide copies.  Unfortunately, MSVC makes that
-    // impossible for small types, which it will pass in a single register or
-    // stack slot. Most objects with dtors are large-ish, so handle that early.
-    // We can't call out all large objects as being indirect because there are
-    // multiple x64 calling conventions and the C++ ABI code shouldn't dictate
-    // how we pass large POD types.
-
-    // Note: This permits small classes with nontrivial destructors to be
-    // passed in registers, which is non-conforming.
-    if (CopyCtorIsTrivial &&
-        S.getASTContext().getTypeSize(D->getTypeForDecl()) <= 64)
-      return true;
-    return false;
-  }
-
-  // Per C++ [class.temporary]p3, the relevant condition is:
-  //   each copy constructor, move constructor, and destructor of X is
-  //   either trivial or deleted, and X has at least one non-deleted copy
-  //   or move constructor
-  bool HasNonDeletedCopyOrMove = false;
-
-  if (D->needsImplicitCopyConstructor() &&
-      !D->defaultedCopyConstructorIsDeleted()) {
-    if (!D->hasTrivialCopyConstructorForCall())
-      return false;
-    HasNonDeletedCopyOrMove = true;
-  }
-
-  if (S.getLangOpts().CPlusPlus11 && D->needsImplicitMoveConstructor() &&
-      !D->defaultedMoveConstructorIsDeleted()) {
-    if (!D->hasTrivialMoveConstructorForCall())
-      return false;
-    HasNonDeletedCopyOrMove = true;
-  }
-
-  if (D->needsImplicitDestructor() && !D->defaultedDestructorIsDeleted() &&
-      !D->hasTrivialDestructorForCall())
-    return false;
-
-  for (const CXXMethodDecl *MD : D->methods()) {
-    if (MD->isDeleted())
-      continue;
-
-    auto *CD = dyn_cast<CXXConstructorDecl>(MD);
-    if (CD && CD->isCopyOrMoveConstructor())
-      HasNonDeletedCopyOrMove = true;
-    else if (!isa<CXXDestructorDecl>(MD))
-      continue;
-
-    if (!MD->isTrivialForCall())
-      return false;
-  }
-
-  return HasNonDeletedCopyOrMove;
-}
-
-/// Perform semantic checks on a class definition that has been
-/// completing, introducing implicitly-declared members, checking for
-/// abstract types, etc.
-void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
-  if (!Record)
-    return;
-
-  if (Record->isAbstract() && !Record->isInvalidDecl()) {
-    AbstractUsageInfo Info(*this, Record);
-    CheckAbstractClassUsage(Info, Record);
-  }
-
-  // If this is not an aggregate type and has no user-declared constructor,
-  // complain about any non-static data members of reference or const scalar
-  // type, since they will never get initializers.
-  if (!Record->isInvalidDecl() && !Record->isDependentType() &&
-      !Record->isAggregate() && !Record->hasUserDeclaredConstructor() &&
-      !Record->isLambda()) {
-    bool Complained = false;
-    for (const auto *F : Record->fields()) {
-      if (F->hasInClassInitializer() || F->isUnnamedBitfield())
-        continue;
-
-      if (F->getType()->isReferenceType() ||
-          (F->getType().isConstQualified() && F->getType()->isScalarType())) {
-        if (!Complained) {
-          Diag(Record->getLocation(), diag::warn_no_constructor_for_refconst)
-            << Record->getTagKind() << Record;
-          Complained = true;
-        }
-
-        Diag(F->getLocation(), diag::note_refconst_member_not_initialized)
-          << F->getType()->isReferenceType()
-          << F->getDeclName();
-      }
-    }
-  }
-
-  if (Record->getIdentifier()) {
-    // C++ [class.mem]p13:
-    //   If T is the name of a class, then each of the following shall have a
-    //   name different from T:
-    //     - every member of every anonymous union that is a member of class T.
-    //
-    // C++ [class.mem]p14:
-    //   In addition, if class T has a user-declared constructor (12.1), every
-    //   non-static data member of class T shall have a name different from T.
-    DeclContext::lookup_result R = Record->lookup(Record->getDeclName());
-    for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
-         ++I) {
-      NamedDecl *D = (*I)->getUnderlyingDecl();
-      if (((isa<FieldDecl>(D) || isa<UnresolvedUsingValueDecl>(D)) &&
-           Record->hasUserDeclaredConstructor()) ||
-          isa<IndirectFieldDecl>(D)) {
-        Diag((*I)->getLocation(), diag::err_member_name_of_class)
-          << D->getDeclName();
-        break;
-      }
-    }
-  }
-
-  // Warn if the class has virtual methods but non-virtual public destructor.
-  if (Record->isPolymorphic() && !Record->isDependentType()) {
-    CXXDestructorDecl *dtor = Record->getDestructor();
-    if ((!dtor || (!dtor->isVirtual() && dtor->getAccess() == AS_public)) &&
-        !Record->hasAttr<FinalAttr>())
-      Diag(dtor ? dtor->getLocation() : Record->getLocation(),
-           diag::warn_non_virtual_dtor) << Context.getRecordType(Record);
-  }
-
-  if (Record->isAbstract()) {
-    if (FinalAttr *FA = Record->getAttr<FinalAttr>()) {
-      Diag(Record->getLocation(), diag::warn_abstract_final_class)
-        << FA->isSpelledAsSealed();
-      DiagnoseAbstractType(Record);
-    }
-  }
-
-  // See if trivial_abi has to be dropped.
-  if (Record->hasAttr<TrivialABIAttr>())
-    checkIllFormedTrivialABIStruct(*Record);
-
-  // Set HasTrivialSpecialMemberForCall if the record has attribute
-  // "trivial_abi".
-  bool HasTrivialABI = Record->hasAttr<TrivialABIAttr>();
-
-  if (HasTrivialABI)
-    Record->setHasTrivialSpecialMemberForCall();
-
-  bool HasMethodWithOverrideControl = false,
-       HasOverridingMethodWithoutOverrideControl = false;
-  if (!Record->isDependentType()) {
-    for (auto *M : Record->methods()) {
-      // See if a method overloads virtual methods in a base
-      // class without overriding any.
-      if (!M->isStatic())
-        DiagnoseHiddenVirtualMethods(M);
-      if (M->hasAttr<OverrideAttr>())
-        HasMethodWithOverrideControl = true;
-      else if (M->size_overridden_methods() > 0)
-        HasOverridingMethodWithoutOverrideControl = true;
-      // Check whether the explicitly-defaulted special members are valid.
-      if (!M->isInvalidDecl() && M->isExplicitlyDefaulted())
-        CheckExplicitlyDefaultedSpecialMember(M);
-
-      // For an explicitly defaulted or deleted special member, we defer
-      // determining triviality until the class is complete. That time is now!
-      CXXSpecialMember CSM = getSpecialMember(M);
-      if (!M->isImplicit() && !M->isUserProvided()) {
-        if (CSM != CXXInvalid) {
-          M->setTrivial(SpecialMemberIsTrivial(M, CSM));
-          // Inform the class that we've finished declaring this member.
-          Record->finishedDefaultedOrDeletedMember(M);
-          M->setTrivialForCall(
-              HasTrivialABI ||
-              SpecialMemberIsTrivial(M, CSM, TAH_ConsiderTrivialABI));
-          Record->setTrivialForCallFlags(M);
-        }
-      }
-
-      // Set triviality for the purpose of calls if this is a user-provided
-      // copy/move constructor or destructor.
-      if ((CSM == CXXCopyConstructor || CSM == CXXMoveConstructor ||
-           CSM == CXXDestructor) && M->isUserProvided()) {
-        M->setTrivialForCall(HasTrivialABI);
-        Record->setTrivialForCallFlags(M);
-      }
-
-      if (!M->isInvalidDecl() && M->isExplicitlyDefaulted() &&
-          M->hasAttr<DLLExportAttr>()) {
-        if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
-            M->isTrivial() &&
-            (CSM == CXXDefaultConstructor || CSM == CXXCopyConstructor ||
-             CSM == CXXDestructor))
-          M->dropAttr<DLLExportAttr>();
-
-        if (M->hasAttr<DLLExportAttr>()) {
-          DefineImplicitSpecialMember(*this, M, M->getLocation());
-          ActOnFinishInlineFunctionDef(M);
-        }
-      }
-    }
-  }
-
-  if (HasMethodWithOverrideControl &&
-      HasOverridingMethodWithoutOverrideControl) {
-    // At least one method has the 'override' control declared.
-    // Diagnose all other overridden methods which do not have 'override' specified on them.
-    for (auto *M : Record->methods())
-      DiagnoseAbsenceOfOverrideControl(M);
-  }
-
-  // ms_struct is a request to use the same ABI rules as MSVC.  Check
-  // whether this class uses any C++ features that are implemented
-  // completely differently in MSVC, and if so, emit a diagnostic.
-  // That diagnostic defaults to an error, but we allow projects to
-  // map it down to a warning (or ignore it).  It's a fairly common
-  // practice among users of the ms_struct pragma to mass-annotate
-  // headers, sweeping up a bunch of types that the project doesn't
-  // really rely on MSVC-compatible layout for.  We must therefore
-  // support "ms_struct except for C++ stuff" as a secondary ABI.
-  if (Record->isMsStruct(Context) &&
-      (Record->isPolymorphic() || Record->getNumBases())) {
-    Diag(Record->getLocation(), diag::warn_cxx_ms_struct);
-  }
-
-  checkClassLevelDLLAttribute(Record);
-  checkClassLevelCodeSegAttribute(Record);
-
-  bool ClangABICompat4 =
-      Context.getLangOpts().getClangABICompat() <= LangOptions::ClangABI::Ver4;
-  TargetInfo::CallingConvKind CCK =
-      Context.getTargetInfo().getCallingConvKind(ClangABICompat4);
-  bool CanPass = canPassInRegisters(*this, Record, CCK);
-
-  // Do not change ArgPassingRestrictions if it has already been set to
-  // APK_CanNeverPassInRegs.
-  if (Record->getArgPassingRestrictions() != RecordDecl::APK_CanNeverPassInRegs)
-    Record->setArgPassingRestrictions(CanPass
-                                          ? RecordDecl::APK_CanPassInRegs
-                                          : RecordDecl::APK_CannotPassInRegs);
-
-  // If canPassInRegisters returns true despite the record having a non-trivial
-  // destructor, the record is destructed in the callee. This happens only when
-  // the record or one of its subobjects has a field annotated with trivial_abi
-  // or a field qualified with ObjC __strong/__weak.
-  if (Context.getTargetInfo().getCXXABI().areArgsDestroyedLeftToRightInCallee())
-    Record->setParamDestroyedInCallee(true);
-  else if (Record->hasNonTrivialDestructor())
-    Record->setParamDestroyedInCallee(CanPass);
-
-  if (getLangOpts().ForceEmitVTables) {
-    // If we want to emit all the vtables, we need to mark it as used.  This
-    // is especially required for cases like vtable assumption loads.
-    MarkVTableUsed(Record->getInnerLocStart(), Record);
-  }
-}
-
-/// Look up the special member function that would be called by a special
-/// member function for a subobject of class type.
-///
-/// \param Class The class type of the subobject.
-/// \param CSM The kind of special member function.
-/// \param FieldQuals If the subobject is a field, its cv-qualifiers.
-/// \param ConstRHS True if this is a copy operation with a const object
-///        on its RHS, that is, if the argument to the outer special member
-///        function is 'const' and this is not a field marked 'mutable'.
-static Sema::SpecialMemberOverloadResult lookupCallFromSpecialMember(
-    Sema &S, CXXRecordDecl *Class, Sema::CXXSpecialMember CSM,
-    unsigned FieldQuals, bool ConstRHS) {
-  unsigned LHSQuals = 0;
-  if (CSM == Sema::CXXCopyAssignment || CSM == Sema::CXXMoveAssignment)
-    LHSQuals = FieldQuals;
-
-  unsigned RHSQuals = FieldQuals;
-  if (CSM == Sema::CXXDefaultConstructor || CSM == Sema::CXXDestructor)
-    RHSQuals = 0;
-  else if (ConstRHS)
-    RHSQuals |= Qualifiers::Const;
-
-  return S.LookupSpecialMember(Class, CSM,
-                               RHSQuals & Qualifiers::Const,
-                               RHSQuals & Qualifiers::Volatile,
-                               false,
-                               LHSQuals & Qualifiers::Const,
-                               LHSQuals & Qualifiers::Volatile);
-}
-
-class Sema::InheritedConstructorInfo {
-  Sema &S;
-  SourceLocation UseLoc;
-
-  /// A mapping from the base classes through which the constructor was
-  /// inherited to the using shadow declaration in that base class (or a null
-  /// pointer if the constructor was declared in that base class).
-  llvm::DenseMap<CXXRecordDecl *, ConstructorUsingShadowDecl *>
-      InheritedFromBases;
-
-public:
-  InheritedConstructorInfo(Sema &S, SourceLocation UseLoc,
-                           ConstructorUsingShadowDecl *Shadow)
-      : S(S), UseLoc(UseLoc) {
-    bool DiagnosedMultipleConstructedBases = false;
-    CXXRecordDecl *ConstructedBase = nullptr;
-    UsingDecl *ConstructedBaseUsing = nullptr;
-
-    // Find the set of such base class subobjects and check that there's a
-    // unique constructed subobject.
-    for (auto *D : Shadow->redecls()) {
-      auto *DShadow = cast<ConstructorUsingShadowDecl>(D);
-      auto *DNominatedBase = DShadow->getNominatedBaseClass();
-      auto *DConstructedBase = DShadow->getConstructedBaseClass();
-
-      InheritedFromBases.insert(
-          std::make_pair(DNominatedBase->getCanonicalDecl(),
-                         DShadow->getNominatedBaseClassShadowDecl()));
-      if (DShadow->constructsVirtualBase())
-        InheritedFromBases.insert(
-            std::make_pair(DConstructedBase->getCanonicalDecl(),
-                           DShadow->getConstructedBaseClassShadowDecl()));
-      else
-        assert(DNominatedBase == DConstructedBase);
-
-      // [class.inhctor.init]p2:
-      //   If the constructor was inherited from multiple base class subobjects
-      //   of type B, the program is ill-formed.
-      if (!ConstructedBase) {
-        ConstructedBase = DConstructedBase;
-        ConstructedBaseUsing = D->getUsingDecl();
-      } else if (ConstructedBase != DConstructedBase &&
-                 !Shadow->isInvalidDecl()) {
-        if (!DiagnosedMultipleConstructedBases) {
-          S.Diag(UseLoc, diag::err_ambiguous_inherited_constructor)
-              << Shadow->getTargetDecl();
-          S.Diag(ConstructedBaseUsing->getLocation(),
-               diag::note_ambiguous_inherited_constructor_using)
-              << ConstructedBase;
-          DiagnosedMultipleConstructedBases = true;
-        }
-        S.Diag(D->getUsingDecl()->getLocation(),
-               diag::note_ambiguous_inherited_constructor_using)
-            << DConstructedBase;
-      }
-    }
-
-    if (DiagnosedMultipleConstructedBases)
-      Shadow->setInvalidDecl();
-  }
-
-  /// Find the constructor to use for inherited construction of a base class,
-  /// and whether that base class constructor inherits the constructor from a
-  /// virtual base class (in which case it won't actually invoke it).
-  std::pair<CXXConstructorDecl *, bool>
-  findConstructorForBase(CXXRecordDecl *Base, CXXConstructorDecl *Ctor) const {
-    auto It = InheritedFromBases.find(Base->getCanonicalDecl());
-    if (It == InheritedFromBases.end())
-      return std::make_pair(nullptr, false);
-
-    // This is an intermediary class.
-    if (It->second)
-      return std::make_pair(
-          S.findInheritingConstructor(UseLoc, Ctor, It->second),
-          It->second->constructsVirtualBase());
-
-    // This is the base class from which the constructor was inherited.
-    return std::make_pair(Ctor, false);
-  }
-};
-
-/// Is the special member function which would be selected to perform the
-/// specified operation on the specified class type a constexpr constructor?
-static bool
-specialMemberIsConstexpr(Sema &S, CXXRecordDecl *ClassDecl,
-                         Sema::CXXSpecialMember CSM, unsigned Quals,
-                         bool ConstRHS,
-                         CXXConstructorDecl *InheritedCtor = nullptr,
-                         Sema::InheritedConstructorInfo *Inherited = nullptr) {
-  // If we're inheriting a constructor, see if we need to call it for this base
-  // class.
-  if (InheritedCtor) {
-    assert(CSM == Sema::CXXDefaultConstructor);
-    auto BaseCtor =
-        Inherited->findConstructorForBase(ClassDecl, InheritedCtor).first;
-    if (BaseCtor)
-      return BaseCtor->isConstexpr();
-  }
-
-  if (CSM == Sema::CXXDefaultConstructor)
-    return ClassDecl->hasConstexprDefaultConstructor();
-
-  Sema::SpecialMemberOverloadResult SMOR =
-      lookupCallFromSpecialMember(S, ClassDecl, CSM, Quals, ConstRHS);
-  if (!SMOR.getMethod())
-    // A constructor we wouldn't select can't be "involved in initializing"
-    // anything.
-    return true;
-  return SMOR.getMethod()->isConstexpr();
-}
-
-/// Determine whether the specified special member function would be constexpr
-/// if it were implicitly defined.
-static bool defaultedSpecialMemberIsConstexpr(
-    Sema &S, CXXRecordDecl *ClassDecl, Sema::CXXSpecialMember CSM,
-    bool ConstArg, CXXConstructorDecl *InheritedCtor = nullptr,
-    Sema::InheritedConstructorInfo *Inherited = nullptr) {
-  if (!S.getLangOpts().CPlusPlus11)
-    return false;
-
-  // C++11 [dcl.constexpr]p4:
-  // In the definition of a constexpr constructor [...]
-  bool Ctor = true;
-  switch (CSM) {
-  case Sema::CXXDefaultConstructor:
-    if (Inherited)
-      break;
-    // Since default constructor lookup is essentially trivial (and cannot
-    // involve, for instance, template instantiation), we compute whether a
-    // defaulted default constructor is constexpr directly within CXXRecordDecl.
-    //
-    // This is important for performance; we need to know whether the default
-    // constructor is constexpr to determine whether the type is a literal type.
-    return ClassDecl->defaultedDefaultConstructorIsConstexpr();
-
-  case Sema::CXXCopyConstructor:
-  case Sema::CXXMoveConstructor:
-    // For copy or move constructors, we need to perform overload resolution.
-    break;
-
-  case Sema::CXXCopyAssignment:
-  case Sema::CXXMoveAssignment:
-    if (!S.getLangOpts().CPlusPlus14)
-      return false;
-    // In C++1y, we need to perform overload resolution.
-    Ctor = false;
-    break;
-
-  case Sema::CXXDestructor:
-  case Sema::CXXInvalid:
-    return false;
-  }
-
-  //   -- if the class is a non-empty union, or for each non-empty anonymous
-  //      union member of a non-union class, exactly one non-static data member
-  //      shall be initialized; [DR1359]
-  //
-  // If we squint, this is guaranteed, since exactly one non-static data member
-  // will be initialized (if the constructor isn't deleted), we just don't know
-  // which one.
-  if (Ctor && ClassDecl->isUnion())
-    return CSM == Sema::CXXDefaultConstructor
-               ? ClassDecl->hasInClassInitializer() ||
-                     !ClassDecl->hasVariantMembers()
-               : true;
-
-  //   -- the class shall not have any virtual base classes;
-  if (Ctor && ClassDecl->getNumVBases())
-    return false;
-
-  // C++1y [class.copy]p26:
-  //   -- [the class] is a literal type, and
-  if (!Ctor && !ClassDecl->isLiteral())
-    return false;
-
-  //   -- every constructor involved in initializing [...] base class
-  //      sub-objects shall be a constexpr constructor;
-  //   -- the assignment operator selected to copy/move each direct base
-  //      class is a constexpr function, and
-  for (const auto &B : ClassDecl->bases()) {
-    const RecordType *BaseType = B.getType()->getAs<RecordType>();
-    if (!BaseType) continue;
-
-    CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
-    if (!specialMemberIsConstexpr(S, BaseClassDecl, CSM, 0, ConstArg,
-                                  InheritedCtor, Inherited))
-      return false;
-  }
-
-  //   -- every constructor involved in initializing non-static data members
-  //      [...] shall be a constexpr constructor;
-  //   -- every non-static data member and base class sub-object shall be
-  //      initialized
-  //   -- for each non-static data member of X that is of class type (or array
-  //      thereof), the assignment operator selected to copy/move that member is
-  //      a constexpr function
-  for (const auto *F : ClassDecl->fields()) {
-    if (F->isInvalidDecl())
-      continue;
-    if (CSM == Sema::CXXDefaultConstructor && F->hasInClassInitializer())
-      continue;
-    QualType BaseType = S.Context.getBaseElementType(F->getType());
-    if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) {
-      CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
-      if (!specialMemberIsConstexpr(S, FieldRecDecl, CSM,
-                                    BaseType.getCVRQualifiers(),
-                                    ConstArg && !F->isMutable()))
-        return false;
-    } else if (CSM == Sema::CXXDefaultConstructor) {
-      return false;
-    }
-  }
-
-  // All OK, it's constexpr!
-  return true;
-}
-
-static Sema::ImplicitExceptionSpecification
-ComputeDefaultedSpecialMemberExceptionSpec(
-    Sema &S, SourceLocation Loc, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
-    Sema::InheritedConstructorInfo *ICI);
-
-static Sema::ImplicitExceptionSpecification
-computeImplicitExceptionSpec(Sema &S, SourceLocation Loc, CXXMethodDecl *MD) {
-  auto CSM = S.getSpecialMember(MD);
-  if (CSM != Sema::CXXInvalid)
-    return ComputeDefaultedSpecialMemberExceptionSpec(S, Loc, MD, CSM, nullptr);
-
-  auto *CD = cast<CXXConstructorDecl>(MD);
-  assert(CD->getInheritedConstructor() &&
-         "only special members have implicit exception specs");
-  Sema::InheritedConstructorInfo ICI(
-      S, Loc, CD->getInheritedConstructor().getShadowDecl());
-  return ComputeDefaultedSpecialMemberExceptionSpec(
-      S, Loc, CD, Sema::CXXDefaultConstructor, &ICI);
-}
-
-static FunctionProtoType::ExtProtoInfo getImplicitMethodEPI(Sema &S,
-                                                            CXXMethodDecl *MD) {
-  FunctionProtoType::ExtProtoInfo EPI;
-
-  // Build an exception specification pointing back at this member.
-  EPI.ExceptionSpec.Type = EST_Unevaluated;
-  EPI.ExceptionSpec.SourceDecl = MD;
-
-  // Set the calling convention to the default for C++ instance methods.
-  EPI.ExtInfo = EPI.ExtInfo.withCallingConv(
-      S.Context.getDefaultCallingConvention(/*IsVariadic=*/false,
-                                            /*IsCXXMethod=*/true));
-  return EPI;
-}
-
-void Sema::EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD) {
-  const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
-  if (FPT->getExceptionSpecType() != EST_Unevaluated)
-    return;
-
-  // Evaluate the exception specification.
-  auto IES = computeImplicitExceptionSpec(*this, Loc, MD);
-  auto ESI = IES.getExceptionSpec();
-
-  // Update the type of the special member to use it.
-  UpdateExceptionSpec(MD, ESI);
-
-  // A user-provided destructor can be defined outside the class. When that
-  // happens, be sure to update the exception specification on both
-  // declarations.
-  const FunctionProtoType *CanonicalFPT =
-    MD->getCanonicalDecl()->getType()->castAs<FunctionProtoType>();
-  if (CanonicalFPT->getExceptionSpecType() == EST_Unevaluated)
-    UpdateExceptionSpec(MD->getCanonicalDecl(), ESI);
-}
-
-void Sema::CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD) {
-  CXXRecordDecl *RD = MD->getParent();
-  CXXSpecialMember CSM = getSpecialMember(MD);
-
-  assert(MD->isExplicitlyDefaulted() && CSM != CXXInvalid &&
-         "not an explicitly-defaulted special member");
-
-  // Whether this was the first-declared instance of the constructor.
-  // This affects whether we implicitly add an exception spec and constexpr.
-  bool First = MD == MD->getCanonicalDecl();
-
-  bool HadError = false;
-
-  // C++11 [dcl.fct.def.default]p1:
-  //   A function that is explicitly defaulted shall
-  //     -- be a special member function (checked elsewhere),
-  //     -- have the same type (except for ref-qualifiers, and except that a
-  //        copy operation can take a non-const reference) as an implicit
-  //        declaration, and
-  //     -- not have default arguments.
-  // C++2a changes the second bullet to instead delete the function if it's
-  // defaulted on its first declaration, unless it's "an assignment operator,
-  // and its return type differs or its parameter type is not a reference".
-  bool DeleteOnTypeMismatch = getLangOpts().CPlusPlus2a && First;
-  bool ShouldDeleteForTypeMismatch = false;
-  unsigned ExpectedParams = 1;
-  if (CSM == CXXDefaultConstructor || CSM == CXXDestructor)
-    ExpectedParams = 0;
-  if (MD->getNumParams() != ExpectedParams) {
-    // This checks for default arguments: a copy or move constructor with a
-    // default argument is classified as a default constructor, and assignment
-    // operations and destructors can't have default arguments.
-    Diag(MD->getLocation(), diag::err_defaulted_special_member_params)
-      << CSM << MD->getSourceRange();
-    HadError = true;
-  } else if (MD->isVariadic()) {
-    if (DeleteOnTypeMismatch)
-      ShouldDeleteForTypeMismatch = true;
-    else {
-      Diag(MD->getLocation(), diag::err_defaulted_special_member_variadic)
-        << CSM << MD->getSourceRange();
-      HadError = true;
-    }
-  }
-
-  const FunctionProtoType *Type = MD->getType()->getAs<FunctionProtoType>();
-
-  bool CanHaveConstParam = false;
-  if (CSM == CXXCopyConstructor)
-    CanHaveConstParam = RD->implicitCopyConstructorHasConstParam();
-  else if (CSM == CXXCopyAssignment)
-    CanHaveConstParam = RD->implicitCopyAssignmentHasConstParam();
-
-  QualType ReturnType = Context.VoidTy;
-  if (CSM == CXXCopyAssignment || CSM == CXXMoveAssignment) {
-    // Check for return type matching.
-    ReturnType = Type->getReturnType();
-
-    QualType DeclType = Context.getTypeDeclType(RD);
-    DeclType = Context.getAddrSpaceQualType(DeclType, MD->getTypeQualifiers().getAddressSpace());
-    QualType ExpectedReturnType = Context.getLValueReferenceType(DeclType);
-
-    if (!Context.hasSameType(ReturnType, ExpectedReturnType)) {
-      Diag(MD->getLocation(), diag::err_defaulted_special_member_return_type)
-        << (CSM == CXXMoveAssignment) << ExpectedReturnType;
-      HadError = true;
-    }
-
-    // A defaulted special member cannot have cv-qualifiers.
-    if (Type->getTypeQuals().hasConst() || Type->getTypeQuals().hasVolatile()) {
-      if (DeleteOnTypeMismatch)
-        ShouldDeleteForTypeMismatch = true;
-      else {
-        Diag(MD->getLocation(), diag::err_defaulted_special_member_quals)
-          << (CSM == CXXMoveAssignment) << getLangOpts().CPlusPlus14;
-        HadError = true;
-      }
-    }
-  }
-
-  // Check for parameter type matching.
-  QualType ArgType = ExpectedParams ? Type->getParamType(0) : QualType();
-  bool HasConstParam = false;
-  if (ExpectedParams && ArgType->isReferenceType()) {
-    // Argument must be reference to possibly-const T.
-    QualType ReferentType = ArgType->getPointeeType();
-    HasConstParam = ReferentType.isConstQualified();
-
-    if (ReferentType.isVolatileQualified()) {
-      if (DeleteOnTypeMismatch)
-        ShouldDeleteForTypeMismatch = true;
-      else {
-        Diag(MD->getLocation(),
-             diag::err_defaulted_special_member_volatile_param) << CSM;
-        HadError = true;
-      }
-    }
-
-    if (HasConstParam && !CanHaveConstParam) {
-      if (DeleteOnTypeMismatch)
-        ShouldDeleteForTypeMismatch = true;
-      else if (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment) {
-        Diag(MD->getLocation(),
-             diag::err_defaulted_special_member_copy_const_param)
-          << (CSM == CXXCopyAssignment);
-        // FIXME: Explain why this special member can't be const.
-        HadError = true;
-      } else {
-        Diag(MD->getLocation(),
-             diag::err_defaulted_special_member_move_const_param)
-          << (CSM == CXXMoveAssignment);
-        HadError = true;
-      }
-    }
-  } else if (ExpectedParams) {
-    // A copy assignment operator can take its argument by value, but a
-    // defaulted one cannot.
-    assert(CSM == CXXCopyAssignment && "unexpected non-ref argument");
-    Diag(MD->getLocation(), diag::err_defaulted_copy_assign_not_ref);
-    HadError = true;
-  }
-
-  // C++11 [dcl.fct.def.default]p2:
-  //   An explicitly-defaulted function may be declared constexpr only if it
-  //   would have been implicitly declared as constexpr,
-  // Do not apply this rule to members of class templates, since core issue 1358
-  // makes such functions always instantiate to constexpr functions. For
-  // functions which cannot be constexpr (for non-constructors in C++11 and for
-  // destructors in C++1y), this is checked elsewhere.
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, RD, CSM,
-                                                     HasConstParam);
-  if ((getLangOpts().CPlusPlus14 ? !isa<CXXDestructorDecl>(MD)
-                                 : isa<CXXConstructorDecl>(MD)) &&
-      MD->isConstexpr() && !Constexpr &&
-      MD->getTemplatedKind() == FunctionDecl::TK_NonTemplate) {
-    Diag(MD->getBeginLoc(), diag::err_incorrect_defaulted_constexpr) << CSM;
-    // FIXME: Explain why the special member can't be constexpr.
-    HadError = true;
-  }
-
-  //   and may have an explicit exception-specification only if it is compatible
-  //   with the exception-specification on the implicit declaration.
-  if (Type->hasExceptionSpec()) {
-    // Delay the check if this is the first declaration of the special member,
-    // since we may not have parsed some necessary in-class initializers yet.
-    if (First) {
-      // If the exception specification needs to be instantiated, do so now,
-      // before we clobber it with an EST_Unevaluated specification below.
-      if (Type->getExceptionSpecType() == EST_Uninstantiated) {
-        InstantiateExceptionSpec(MD->getBeginLoc(), MD);
-        Type = MD->getType()->getAs<FunctionProtoType>();
-      }
-      DelayedDefaultedMemberExceptionSpecs.push_back(std::make_pair(MD, Type));
-    } else
-      CheckExplicitlyDefaultedMemberExceptionSpec(MD, Type);
-  }
-
-  //   If a function is explicitly defaulted on its first declaration,
-  if (First) {
-    //  -- it is implicitly considered to be constexpr if the implicit
-    //     definition would be,
-    MD->setConstexpr(Constexpr);
-
-    //  -- it is implicitly considered to have the same exception-specification
-    //     as if it had been implicitly declared,
-    FunctionProtoType::ExtProtoInfo EPI = Type->getExtProtoInfo();
-    EPI.ExceptionSpec.Type = EST_Unevaluated;
-    EPI.ExceptionSpec.SourceDecl = MD;
-    MD->setType(Context.getFunctionType(ReturnType,
-                                        llvm::makeArrayRef(&ArgType,
-                                                           ExpectedParams),
-                                        EPI));
-  }
-
-  if (ShouldDeleteForTypeMismatch || ShouldDeleteSpecialMember(MD, CSM)) {
-    if (First) {
-      SetDeclDeleted(MD, MD->getLocation());
-      if (!inTemplateInstantiation() && !HadError) {
-        Diag(MD->getLocation(), diag::warn_defaulted_method_deleted) << CSM;
-        if (ShouldDeleteForTypeMismatch) {
-          Diag(MD->getLocation(), diag::note_deleted_type_mismatch) << CSM;
-        } else {
-          ShouldDeleteSpecialMember(MD, CSM, nullptr, /*Diagnose*/true);
-        }
-      }
-      if (ShouldDeleteForTypeMismatch && !HadError) {
-        Diag(MD->getLocation(),
-             diag::warn_cxx17_compat_defaulted_method_type_mismatch) << CSM;
-      }
-    } else {
-      // C++11 [dcl.fct.def.default]p4:
-      //   [For a] user-provided explicitly-defaulted function [...] if such a
-      //   function is implicitly defined as deleted, the program is ill-formed.
-      Diag(MD->getLocation(), diag::err_out_of_line_default_deletes) << CSM;
-      assert(!ShouldDeleteForTypeMismatch && "deleted non-first decl");
-      ShouldDeleteSpecialMember(MD, CSM, nullptr, /*Diagnose*/true);
-      HadError = true;
-    }
-  }
-
-  if (HadError)
-    MD->setInvalidDecl();
-}
-
-/// Check whether the exception specification provided for an
-/// explicitly-defaulted special member matches the exception specification
-/// that would have been generated for an implicit special member, per
-/// C++11 [dcl.fct.def.default]p2.
-void Sema::CheckExplicitlyDefaultedMemberExceptionSpec(
-    CXXMethodDecl *MD, const FunctionProtoType *SpecifiedType) {
-  // If the exception specification was explicitly specified but hadn't been
-  // parsed when the method was defaulted, grab it now.
-  if (SpecifiedType->getExceptionSpecType() == EST_Unparsed)
-    SpecifiedType =
-        MD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
-
-  // Compute the implicit exception specification.
-  CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
-                                                       /*IsCXXMethod=*/true);
-  FunctionProtoType::ExtProtoInfo EPI(CC);
-  auto IES = computeImplicitExceptionSpec(*this, MD->getLocation(), MD);
-  EPI.ExceptionSpec = IES.getExceptionSpec();
-  const FunctionProtoType *ImplicitType = cast<FunctionProtoType>(
-    Context.getFunctionType(Context.VoidTy, None, EPI));
-
-  // Ensure that it matches.
-  CheckEquivalentExceptionSpec(
-    PDiag(diag::err_incorrect_defaulted_exception_spec)
-      << getSpecialMember(MD), PDiag(),
-    ImplicitType, SourceLocation(),
-    SpecifiedType, MD->getLocation());
-}
-
-void Sema::CheckDelayedMemberExceptionSpecs() {
-  decltype(DelayedOverridingExceptionSpecChecks) Overriding;
-  decltype(DelayedEquivalentExceptionSpecChecks) Equivalent;
-  decltype(DelayedDefaultedMemberExceptionSpecs) Defaulted;
-
-  std::swap(Overriding, DelayedOverridingExceptionSpecChecks);
-  std::swap(Equivalent, DelayedEquivalentExceptionSpecChecks);
-  std::swap(Defaulted, DelayedDefaultedMemberExceptionSpecs);
-
-  // Perform any deferred checking of exception specifications for virtual
-  // destructors.
-  for (auto &Check : Overriding)
-    CheckOverridingFunctionExceptionSpec(Check.first, Check.second);
-
-  // Perform any deferred checking of exception specifications for befriended
-  // special members.
-  for (auto &Check : Equivalent)
-    CheckEquivalentExceptionSpec(Check.second, Check.first);
-
-  // Check that any explicitly-defaulted methods have exception specifications
-  // compatible with their implicit exception specifications.
-  for (auto &Spec : Defaulted)
-    CheckExplicitlyDefaultedMemberExceptionSpec(Spec.first, Spec.second);
-}
-
-namespace {
-/// CRTP base class for visiting operations performed by a special member
-/// function (or inherited constructor).
-template<typename Derived>
-struct SpecialMemberVisitor {
-  Sema &S;
-  CXXMethodDecl *MD;
-  Sema::CXXSpecialMember CSM;
-  Sema::InheritedConstructorInfo *ICI;
-
-  // Properties of the special member, computed for convenience.
-  bool IsConstructor = false, IsAssignment = false, ConstArg = false;
-
-  SpecialMemberVisitor(Sema &S, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
-                       Sema::InheritedConstructorInfo *ICI)
-      : S(S), MD(MD), CSM(CSM), ICI(ICI) {
-    switch (CSM) {
-    case Sema::CXXDefaultConstructor:
-    case Sema::CXXCopyConstructor:
-    case Sema::CXXMoveConstructor:
-      IsConstructor = true;
-      break;
-    case Sema::CXXCopyAssignment:
-    case Sema::CXXMoveAssignment:
-      IsAssignment = true;
-      break;
-    case Sema::CXXDestructor:
-      break;
-    case Sema::CXXInvalid:
-      llvm_unreachable("invalid special member kind");
-    }
-
-    if (MD->getNumParams()) {
-      if (const ReferenceType *RT =
-              MD->getParamDecl(0)->getType()->getAs<ReferenceType>())
-        ConstArg = RT->getPointeeType().isConstQualified();
-    }
-  }
-
-  Derived &getDerived() { return static_cast<Derived&>(*this); }
-
-  /// Is this a "move" special member?
-  bool isMove() const {
-    return CSM == Sema::CXXMoveConstructor || CSM == Sema::CXXMoveAssignment;
-  }
-
-  /// Look up the corresponding special member in the given class.
-  Sema::SpecialMemberOverloadResult lookupIn(CXXRecordDecl *Class,
-                                             unsigned Quals, bool IsMutable) {
-    return lookupCallFromSpecialMember(S, Class, CSM, Quals,
-                                       ConstArg && !IsMutable);
-  }
-
-  /// Look up the constructor for the specified base class to see if it's
-  /// overridden due to this being an inherited constructor.
-  Sema::SpecialMemberOverloadResult lookupInheritedCtor(CXXRecordDecl *Class) {
-    if (!ICI)
-      return {};
-    assert(CSM == Sema::CXXDefaultConstructor);
-    auto *BaseCtor =
-      cast<CXXConstructorDecl>(MD)->getInheritedConstructor().getConstructor();
-    if (auto *MD = ICI->findConstructorForBase(Class, BaseCtor).first)
-      return MD;
-    return {};
-  }
-
-  /// A base or member subobject.
-  typedef llvm::PointerUnion<CXXBaseSpecifier*, FieldDecl*> Subobject;
-
-  /// Get the location to use for a subobject in diagnostics.
-  static SourceLocation getSubobjectLoc(Subobject Subobj) {
-    // FIXME: For an indirect virtual base, the direct base leading to
-    // the indirect virtual base would be a more useful choice.
-    if (auto *B = Subobj.dyn_cast<CXXBaseSpecifier*>())
-      return B->getBaseTypeLoc();
-    else
-      return Subobj.get<FieldDecl*>()->getLocation();
-  }
-
-  enum BasesToVisit {
-    /// Visit all non-virtual (direct) bases.
-    VisitNonVirtualBases,
-    /// Visit all direct bases, virtual or not.
-    VisitDirectBases,
-    /// Visit all non-virtual bases, and all virtual bases if the class
-    /// is not abstract.
-    VisitPotentiallyConstructedBases,
-    /// Visit all direct or virtual bases.
-    VisitAllBases
-  };
-
-  // Visit the bases and members of the class.
-  bool visit(BasesToVisit Bases) {
-    CXXRecordDecl *RD = MD->getParent();
-
-    if (Bases == VisitPotentiallyConstructedBases)
-      Bases = RD->isAbstract() ? VisitNonVirtualBases : VisitAllBases;
-
-    for (auto &B : RD->bases())
-      if ((Bases == VisitDirectBases || !B.isVirtual()) &&
-          getDerived().visitBase(&B))
-        return true;
-
-    if (Bases == VisitAllBases)
-      for (auto &B : RD->vbases())
-        if (getDerived().visitBase(&B))
-          return true;
-
-    for (auto *F : RD->fields())
-      if (!F->isInvalidDecl() && !F->isUnnamedBitfield() &&
-          getDerived().visitField(F))
-        return true;
-
-    return false;
-  }
-};
-}
-
-namespace {
-struct SpecialMemberDeletionInfo
-    : SpecialMemberVisitor<SpecialMemberDeletionInfo> {
-  bool Diagnose;
-
-  SourceLocation Loc;
-
-  bool AllFieldsAreConst;
-
-  SpecialMemberDeletionInfo(Sema &S, CXXMethodDecl *MD,
-                            Sema::CXXSpecialMember CSM,
-                            Sema::InheritedConstructorInfo *ICI, bool Diagnose)
-      : SpecialMemberVisitor(S, MD, CSM, ICI), Diagnose(Diagnose),
-        Loc(MD->getLocation()), AllFieldsAreConst(true) {}
-
-  bool inUnion() const { return MD->getParent()->isUnion(); }
-
-  Sema::CXXSpecialMember getEffectiveCSM() {
-    return ICI ? Sema::CXXInvalid : CSM;
-  }
-
-  bool visitBase(CXXBaseSpecifier *Base) { return shouldDeleteForBase(Base); }
-  bool visitField(FieldDecl *Field) { return shouldDeleteForField(Field); }
-
-  bool shouldDeleteForBase(CXXBaseSpecifier *Base);
-  bool shouldDeleteForField(FieldDecl *FD);
-  bool shouldDeleteForAllConstMembers();
-
-  bool shouldDeleteForClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
-                                     unsigned Quals);
-  bool shouldDeleteForSubobjectCall(Subobject Subobj,
-                                    Sema::SpecialMemberOverloadResult SMOR,
-                                    bool IsDtorCallInCtor);
-
-  bool isAccessible(Subobject Subobj, CXXMethodDecl *D);
-};
-}
-
-/// Is the given special member inaccessible when used on the given
-/// sub-object.
-bool SpecialMemberDeletionInfo::isAccessible(Subobject Subobj,
-                                             CXXMethodDecl *target) {
-  /// If we're operating on a base class, the object type is the
-  /// type of this special member.
-  QualType objectTy;
-  AccessSpecifier access = target->getAccess();
-  if (CXXBaseSpecifier *base = Subobj.dyn_cast<CXXBaseSpecifier*>()) {
-    objectTy = S.Context.getTypeDeclType(MD->getParent());
-    access = CXXRecordDecl::MergeAccess(base->getAccessSpecifier(), access);
-
-  // If we're operating on a field, the object type is the type of the field.
-  } else {
-    objectTy = S.Context.getTypeDeclType(target->getParent());
-  }
-
-  return S.isSpecialMemberAccessibleForDeletion(target, access, objectTy);
-}
-
-/// Check whether we should delete a special member due to the implicit
-/// definition containing a call to a special member of a subobject.
-bool SpecialMemberDeletionInfo::shouldDeleteForSubobjectCall(
-    Subobject Subobj, Sema::SpecialMemberOverloadResult SMOR,
-    bool IsDtorCallInCtor) {
-  CXXMethodDecl *Decl = SMOR.getMethod();
-  FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
-
-  int DiagKind = -1;
-
-  if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::NoMemberOrDeleted)
-    DiagKind = !Decl ? 0 : 1;
-  else if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
-    DiagKind = 2;
-  else if (!isAccessible(Subobj, Decl))
-    DiagKind = 3;
-  else if (!IsDtorCallInCtor && Field && Field->getParent()->isUnion() &&
-           !Decl->isTrivial()) {
-    // A member of a union must have a trivial corresponding special member.
-    // As a weird special case, a destructor call from a union's constructor
-    // must be accessible and non-deleted, but need not be trivial. Such a
-    // destructor is never actually called, but is semantically checked as
-    // if it were.
-    DiagKind = 4;
-  }
-
-  if (DiagKind == -1)
-    return false;
-
-  if (Diagnose) {
-    if (Field) {
-      S.Diag(Field->getLocation(),
-             diag::note_deleted_special_member_class_subobject)
-        << getEffectiveCSM() << MD->getParent() << /*IsField*/true
-        << Field << DiagKind << IsDtorCallInCtor;
-    } else {
-      CXXBaseSpecifier *Base = Subobj.get<CXXBaseSpecifier*>();
-      S.Diag(Base->getBeginLoc(),
-             diag::note_deleted_special_member_class_subobject)
-          << getEffectiveCSM() << MD->getParent() << /*IsField*/ false
-          << Base->getType() << DiagKind << IsDtorCallInCtor;
-    }
-
-    if (DiagKind == 1)
-      S.NoteDeletedFunction(Decl);
-    // FIXME: Explain inaccessibility if DiagKind == 3.
-  }
-
-  return true;
-}
-
-/// Check whether we should delete a special member function due to having a
-/// direct or virtual base class or non-static data member of class type M.
-bool SpecialMemberDeletionInfo::shouldDeleteForClassSubobject(
-    CXXRecordDecl *Class, Subobject Subobj, unsigned Quals) {
-  FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
-  bool IsMutable = Field && Field->isMutable();
-
-  // C++11 [class.ctor]p5:
-  // -- any direct or virtual base class, or non-static data member with no
-  //    brace-or-equal-initializer, has class type M (or array thereof) and
-  //    either M has no default constructor or overload resolution as applied
-  //    to M's default constructor results in an ambiguity or in a function
-  //    that is deleted or inaccessible
-  // C++11 [class.copy]p11, C++11 [class.copy]p23:
-  // -- a direct or virtual base class B that cannot be copied/moved because
-  //    overload resolution, as applied to B's corresponding special member,
-  //    results in an ambiguity or a function that is deleted or inaccessible
-  //    from the defaulted special member
-  // C++11 [class.dtor]p5:
-  // -- any direct or virtual base class [...] has a type with a destructor
-  //    that is deleted or inaccessible
-  if (!(CSM == Sema::CXXDefaultConstructor &&
-        Field && Field->hasInClassInitializer()) &&
-      shouldDeleteForSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable),
-                                   false))
-    return true;
-
-  // C++11 [class.ctor]p5, C++11 [class.copy]p11:
-  // -- any direct or virtual base class or non-static data member has a
-  //    type with a destructor that is deleted or inaccessible
-  if (IsConstructor) {
-    Sema::SpecialMemberOverloadResult SMOR =
-        S.LookupSpecialMember(Class, Sema::CXXDestructor,
-                              false, false, false, false, false);
-    if (shouldDeleteForSubobjectCall(Subobj, SMOR, true))
-      return true;
-  }
-
-  return false;
-}
-
-/// Check whether we should delete a special member function due to the class
-/// having a particular direct or virtual base class.
-bool SpecialMemberDeletionInfo::shouldDeleteForBase(CXXBaseSpecifier *Base) {
-  CXXRecordDecl *BaseClass = Base->getType()->getAsCXXRecordDecl();
-  // If program is correct, BaseClass cannot be null, but if it is, the error
-  // must be reported elsewhere.
-  if (!BaseClass)
-    return false;
-  // If we have an inheriting constructor, check whether we're calling an
-  // inherited constructor instead of a default constructor.
-  Sema::SpecialMemberOverloadResult SMOR = lookupInheritedCtor(BaseClass);
-  if (auto *BaseCtor = SMOR.getMethod()) {
-    // Note that we do not check access along this path; other than that,
-    // this is the same as shouldDeleteForSubobjectCall(Base, BaseCtor, false);
-    // FIXME: Check that the base has a usable destructor! Sink this into
-    // shouldDeleteForClassSubobject.
-    if (BaseCtor->isDeleted() && Diagnose) {
-      S.Diag(Base->getBeginLoc(),
-             diag::note_deleted_special_member_class_subobject)
-          << getEffectiveCSM() << MD->getParent() << /*IsField*/ false
-          << Base->getType() << /*Deleted*/ 1 << /*IsDtorCallInCtor*/ false;
-      S.NoteDeletedFunction(BaseCtor);
-    }
-    return BaseCtor->isDeleted();
-  }
-  return shouldDeleteForClassSubobject(BaseClass, Base, 0);
-}
-
-/// Check whether we should delete a special member function due to the class
-/// having a particular non-static data member.
-bool SpecialMemberDeletionInfo::shouldDeleteForField(FieldDecl *FD) {
-  QualType FieldType = S.Context.getBaseElementType(FD->getType());
-  CXXRecordDecl *FieldRecord = FieldType->getAsCXXRecordDecl();
-
-  if (CSM == Sema::CXXDefaultConstructor) {
-    // For a default constructor, all references must be initialized in-class
-    // and, if a union, it must have a non-const member.
-    if (FieldType->isReferenceType() && !FD->hasInClassInitializer()) {
-      if (Diagnose)
-        S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
-          << !!ICI << MD->getParent() << FD << FieldType << /*Reference*/0;
-      return true;
-    }
-    // C++11 [class.ctor]p5: any non-variant non-static data member of
-    // const-qualified type (or array thereof) with no
-    // brace-or-equal-initializer does not have a user-provided default
-    // constructor.
-    if (!inUnion() && FieldType.isConstQualified() &&
-        !FD->hasInClassInitializer() &&
-        (!FieldRecord || !FieldRecord->hasUserProvidedDefaultConstructor())) {
-      if (Diagnose)
-        S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
-          << !!ICI << MD->getParent() << FD << FD->getType() << /*Const*/1;
-      return true;
-    }
-
-    if (inUnion() && !FieldType.isConstQualified())
-      AllFieldsAreConst = false;
-  } else if (CSM == Sema::CXXCopyConstructor) {
-    // For a copy constructor, data members must not be of rvalue reference
-    // type.
-    if (FieldType->isRValueReferenceType()) {
-      if (Diagnose)
-        S.Diag(FD->getLocation(), diag::note_deleted_copy_ctor_rvalue_reference)
-          << MD->getParent() << FD << FieldType;
-      return true;
-    }
-  } else if (IsAssignment) {
-    // For an assignment operator, data members must not be of reference type.
-    if (FieldType->isReferenceType()) {
-      if (Diagnose)
-        S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
-          << isMove() << MD->getParent() << FD << FieldType << /*Reference*/0;
-      return true;
-    }
-    if (!FieldRecord && FieldType.isConstQualified()) {
-      // C++11 [class.copy]p23:
-      // -- a non-static data member of const non-class type (or array thereof)
-      if (Diagnose)
-        S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
-          << isMove() << MD->getParent() << FD << FD->getType() << /*Const*/1;
-      return true;
-    }
-  }
-
-  if (FieldRecord) {
-    // Some additional restrictions exist on the variant members.
-    if (!inUnion() && FieldRecord->isUnion() &&
-        FieldRecord->isAnonymousStructOrUnion()) {
-      bool AllVariantFieldsAreConst = true;
-
-      // FIXME: Handle anonymous unions declared within anonymous unions.
-      for (auto *UI : FieldRecord->fields()) {
-        QualType UnionFieldType = S.Context.getBaseElementType(UI->getType());
-
-        if (!UnionFieldType.isConstQualified())
-          AllVariantFieldsAreConst = false;
-
-        CXXRecordDecl *UnionFieldRecord = UnionFieldType->getAsCXXRecordDecl();
-        if (UnionFieldRecord &&
-            shouldDeleteForClassSubobject(UnionFieldRecord, UI,
-                                          UnionFieldType.getCVRQualifiers()))
-          return true;
-      }
-
-      // At least one member in each anonymous union must be non-const
-      if (CSM == Sema::CXXDefaultConstructor && AllVariantFieldsAreConst &&
-          !FieldRecord->field_empty()) {
-        if (Diagnose)
-          S.Diag(FieldRecord->getLocation(),
-                 diag::note_deleted_default_ctor_all_const)
-            << !!ICI << MD->getParent() << /*anonymous union*/1;
-        return true;
-      }
-
-      // Don't check the implicit member of the anonymous union type.
-      // This is technically non-conformant, but sanity demands it.
-      return false;
-    }
-
-    if (shouldDeleteForClassSubobject(FieldRecord, FD,
-                                      FieldType.getCVRQualifiers()))
-      return true;
-  }
-
-  return false;
-}
-
-/// C++11 [class.ctor] p5:
-///   A defaulted default constructor for a class X is defined as deleted if
-/// X is a union and all of its variant members are of const-qualified type.
-bool SpecialMemberDeletionInfo::shouldDeleteForAllConstMembers() {
-  // This is a silly definition, because it gives an empty union a deleted
-  // default constructor. Don't do that.
-  if (CSM == Sema::CXXDefaultConstructor && inUnion() && AllFieldsAreConst) {
-    bool AnyFields = false;
-    for (auto *F : MD->getParent()->fields())
-      if ((AnyFields = !F->isUnnamedBitfield()))
-        break;
-    if (!AnyFields)
-      return false;
-    if (Diagnose)
-      S.Diag(MD->getParent()->getLocation(),
-             diag::note_deleted_default_ctor_all_const)
-        << !!ICI << MD->getParent() << /*not anonymous union*/0;
-    return true;
-  }
-  return false;
-}
-
-/// Determine whether a defaulted special member function should be defined as
-/// deleted, as specified in C++11 [class.ctor]p5, C++11 [class.copy]p11,
-/// C++11 [class.copy]p23, and C++11 [class.dtor]p5.
-bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
-                                     InheritedConstructorInfo *ICI,
-                                     bool Diagnose) {
-  if (MD->isInvalidDecl())
-    return false;
-  CXXRecordDecl *RD = MD->getParent();
-  assert(!RD->isDependentType() && "do deletion after instantiation");
-  if (!LangOpts.CPlusPlus11 || RD->isInvalidDecl())
-    return false;
-
-  // C++11 [expr.lambda.prim]p19:
-  //   The closure type associated with a lambda-expression has a
-  //   deleted (8.4.3) default constructor and a deleted copy
-  //   assignment operator.
-  // C++2a adds back these operators if the lambda has no capture-default.
-  if (RD->isLambda() && !RD->lambdaIsDefaultConstructibleAndAssignable() &&
-      (CSM == CXXDefaultConstructor || CSM == CXXCopyAssignment)) {
-    if (Diagnose)
-      Diag(RD->getLocation(), diag::note_lambda_decl);
-    return true;
-  }
-
-  // For an anonymous struct or union, the copy and assignment special members
-  // will never be used, so skip the check. For an anonymous union declared at
-  // namespace scope, the constructor and destructor are used.
-  if (CSM != CXXDefaultConstructor && CSM != CXXDestructor &&
-      RD->isAnonymousStructOrUnion())
-    return false;
-
-  // C++11 [class.copy]p7, p18:
-  //   If the class definition declares a move constructor or move assignment
-  //   operator, an implicitly declared copy constructor or copy assignment
-  //   operator is defined as deleted.
-  if (MD->isImplicit() &&
-      (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)) {
-    CXXMethodDecl *UserDeclaredMove = nullptr;
-
-    // In Microsoft mode up to MSVC 2013, a user-declared move only causes the
-    // deletion of the corresponding copy operation, not both copy operations.
-    // MSVC 2015 has adopted the standards conforming behavior.
-    bool DeletesOnlyMatchingCopy =
-        getLangOpts().MSVCCompat &&
-        !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015);
-
-    if (RD->hasUserDeclaredMoveConstructor() &&
-        (!DeletesOnlyMatchingCopy || CSM == CXXCopyConstructor)) {
-      if (!Diagnose) return true;
-
-      // Find any user-declared move constructor.
-      for (auto *I : RD->ctors()) {
-        if (I->isMoveConstructor()) {
-          UserDeclaredMove = I;
-          break;
-        }
-      }
-      assert(UserDeclaredMove);
-    } else if (RD->hasUserDeclaredMoveAssignment() &&
-               (!DeletesOnlyMatchingCopy || CSM == CXXCopyAssignment)) {
-      if (!Diagnose) return true;
-
-      // Find any user-declared move assignment operator.
-      for (auto *I : RD->methods()) {
-        if (I->isMoveAssignmentOperator()) {
-          UserDeclaredMove = I;
-          break;
-        }
-      }
-      assert(UserDeclaredMove);
-    }
-
-    if (UserDeclaredMove) {
-      Diag(UserDeclaredMove->getLocation(),
-           diag::note_deleted_copy_user_declared_move)
-        << (CSM == CXXCopyAssignment) << RD
-        << UserDeclaredMove->isMoveAssignmentOperator();
-      return true;
-    }
-  }
-
-  // Do access control from the special member function
-  ContextRAII MethodContext(*this, MD);
-
-  // C++11 [class.dtor]p5:
-  // -- for a virtual destructor, lookup of the non-array deallocation function
-  //    results in an ambiguity or in a function that is deleted or inaccessible
-  if (CSM == CXXDestructor && MD->isVirtual()) {
-    FunctionDecl *OperatorDelete = nullptr;
-    DeclarationName Name =
-      Context.DeclarationNames.getCXXOperatorName(OO_Delete);
-    if (FindDeallocationFunction(MD->getLocation(), MD->getParent(), Name,
-                                 OperatorDelete, /*Diagnose*/false)) {
-      if (Diagnose)
-        Diag(RD->getLocation(), diag::note_deleted_dtor_no_operator_delete);
-      return true;
-    }
-  }
-
-  SpecialMemberDeletionInfo SMI(*this, MD, CSM, ICI, Diagnose);
-
-  // Per DR1611, do not consider virtual bases of constructors of abstract
-  // classes, since we are not going to construct them.
-  // Per DR1658, do not consider virtual bases of destructors of abstract
-  // classes either.
-  // Per DR2180, for assignment operators we only assign (and thus only
-  // consider) direct bases.
-  if (SMI.visit(SMI.IsAssignment ? SMI.VisitDirectBases
-                                 : SMI.VisitPotentiallyConstructedBases))
-    return true;
-
-  if (SMI.shouldDeleteForAllConstMembers())
-    return true;
-
-  if (getLangOpts().CUDA) {
-    // We should delete the special member in CUDA mode if target inference
-    // failed.
-    // For inherited constructors (non-null ICI), CSM may be passed so that MD
-    // is treated as certain special member, which may not reflect what special
-    // member MD really is. However inferCUDATargetForImplicitSpecialMember
-    // expects CSM to match MD, therefore recalculate CSM.
-    assert(ICI || CSM == getSpecialMember(MD));
-    auto RealCSM = CSM;
-    if (ICI)
-      RealCSM = getSpecialMember(MD);
-
-    return inferCUDATargetForImplicitSpecialMember(RD, RealCSM, MD,
-                                                   SMI.ConstArg, Diagnose);
-  }
-
-  return false;
-}
-
-/// Perform lookup for a special member of the specified kind, and determine
-/// whether it is trivial. If the triviality can be determined without the
-/// lookup, skip it. This is intended for use when determining whether a
-/// special member of a containing object is trivial, and thus does not ever
-/// perform overload resolution for default constructors.
-///
-/// If \p Selected is not \c NULL, \c *Selected will be filled in with the
-/// member that was most likely to be intended to be trivial, if any.
-///
-/// If \p ForCall is true, look at CXXRecord::HasTrivialSpecialMembersForCall to
-/// determine whether the special member is trivial.
-static bool findTrivialSpecialMember(Sema &S, CXXRecordDecl *RD,
-                                     Sema::CXXSpecialMember CSM, unsigned Quals,
-                                     bool ConstRHS,
-                                     Sema::TrivialABIHandling TAH,
-                                     CXXMethodDecl **Selected) {
-  if (Selected)
-    *Selected = nullptr;
-
-  switch (CSM) {
-  case Sema::CXXInvalid:
-    llvm_unreachable("not a special member");
-
-  case Sema::CXXDefaultConstructor:
-    // C++11 [class.ctor]p5:
-    //   A default constructor is trivial if:
-    //    - all the [direct subobjects] have trivial default constructors
-    //
-    // Note, no overload resolution is performed in this case.
-    if (RD->hasTrivialDefaultConstructor())
-      return true;
-
-    if (Selected) {
-      // If there's a default constructor which could have been trivial, dig it
-      // out. Otherwise, if there's any user-provided default constructor, point
-      // to that as an example of why there's not a trivial one.
-      CXXConstructorDecl *DefCtor = nullptr;
-      if (RD->needsImplicitDefaultConstructor())
-        S.DeclareImplicitDefaultConstructor(RD);
-      for (auto *CI : RD->ctors()) {
-        if (!CI->isDefaultConstructor())
-          continue;
-        DefCtor = CI;
-        if (!DefCtor->isUserProvided())
-          break;
-      }
-
-      *Selected = DefCtor;
-    }
-
-    return false;
-
-  case Sema::CXXDestructor:
-    // C++11 [class.dtor]p5:
-    //   A destructor is trivial if:
-    //    - all the direct [subobjects] have trivial destructors
-    if (RD->hasTrivialDestructor() ||
-        (TAH == Sema::TAH_ConsiderTrivialABI &&
-         RD->hasTrivialDestructorForCall()))
-      return true;
-
-    if (Selected) {
-      if (RD->needsImplicitDestructor())
-        S.DeclareImplicitDestructor(RD);
-      *Selected = RD->getDestructor();
-    }
-
-    return false;
-
-  case Sema::CXXCopyConstructor:
-    // C++11 [class.copy]p12:
-    //   A copy constructor is trivial if:
-    //    - the constructor selected to copy each direct [subobject] is trivial
-    if (RD->hasTrivialCopyConstructor() ||
-        (TAH == Sema::TAH_ConsiderTrivialABI &&
-         RD->hasTrivialCopyConstructorForCall())) {
-      if (Quals == Qualifiers::Const)
-        // We must either select the trivial copy constructor or reach an
-        // ambiguity; no need to actually perform overload resolution.
-        return true;
-    } else if (!Selected) {
-      return false;
-    }
-    // In C++98, we are not supposed to perform overload resolution here, but we
-    // treat that as a language defect, as suggested on cxx-abi-dev, to treat
-    // cases like B as having a non-trivial copy constructor:
-    //   struct A { template<typename T> A(T&); };
-    //   struct B { mutable A a; };
-    goto NeedOverloadResolution;
-
-  case Sema::CXXCopyAssignment:
-    // C++11 [class.copy]p25:
-    //   A copy assignment operator is trivial if:
-    //    - the assignment operator selected to copy each direct [subobject] is
-    //      trivial
-    if (RD->hasTrivialCopyAssignment()) {
-      if (Quals == Qualifiers::Const)
-        return true;
-    } else if (!Selected) {
-      return false;
-    }
-    // In C++98, we are not supposed to perform overload resolution here, but we
-    // treat that as a language defect.
-    goto NeedOverloadResolution;
-
-  case Sema::CXXMoveConstructor:
-  case Sema::CXXMoveAssignment:
-  NeedOverloadResolution:
-    Sema::SpecialMemberOverloadResult SMOR =
-        lookupCallFromSpecialMember(S, RD, CSM, Quals, ConstRHS);
-
-    // The standard doesn't describe how to behave if the lookup is ambiguous.
-    // We treat it as not making the member non-trivial, just like the standard
-    // mandates for the default constructor. This should rarely matter, because
-    // the member will also be deleted.
-    if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
-      return true;
-
-    if (!SMOR.getMethod()) {
-      assert(SMOR.getKind() ==
-             Sema::SpecialMemberOverloadResult::NoMemberOrDeleted);
-      return false;
-    }
-
-    // We deliberately don't check if we found a deleted special member. We're
-    // not supposed to!
-    if (Selected)
-      *Selected = SMOR.getMethod();
-
-    if (TAH == Sema::TAH_ConsiderTrivialABI &&
-        (CSM == Sema::CXXCopyConstructor || CSM == Sema::CXXMoveConstructor))
-      return SMOR.getMethod()->isTrivialForCall();
-    return SMOR.getMethod()->isTrivial();
-  }
-
-  llvm_unreachable("unknown special method kind");
-}
-
-static CXXConstructorDecl *findUserDeclaredCtor(CXXRecordDecl *RD) {
-  for (auto *CI : RD->ctors())
-    if (!CI->isImplicit())
-      return CI;
-
-  // Look for constructor templates.
-  typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl> tmpl_iter;
-  for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end()); TI != TE; ++TI) {
-    if (CXXConstructorDecl *CD =
-          dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl()))
-      return CD;
-  }
-
-  return nullptr;
-}
-
-/// The kind of subobject we are checking for triviality. The values of this
-/// enumeration are used in diagnostics.
-enum TrivialSubobjectKind {
-  /// The subobject is a base class.
-  TSK_BaseClass,
-  /// The subobject is a non-static data member.
-  TSK_Field,
-  /// The object is actually the complete object.
-  TSK_CompleteObject
-};
-
-/// Check whether the special member selected for a given type would be trivial.
-static bool checkTrivialSubobjectCall(Sema &S, SourceLocation SubobjLoc,
-                                      QualType SubType, bool ConstRHS,
-                                      Sema::CXXSpecialMember CSM,
-                                      TrivialSubobjectKind Kind,
-                                      Sema::TrivialABIHandling TAH, bool Diagnose) {
-  CXXRecordDecl *SubRD = SubType->getAsCXXRecordDecl();
-  if (!SubRD)
-    return true;
-
-  CXXMethodDecl *Selected;
-  if (findTrivialSpecialMember(S, SubRD, CSM, SubType.getCVRQualifiers(),
-                               ConstRHS, TAH, Diagnose ? &Selected : nullptr))
-    return true;
-
-  if (Diagnose) {
-    if (ConstRHS)
-      SubType.addConst();
-
-    if (!Selected && CSM == Sema::CXXDefaultConstructor) {
-      S.Diag(SubobjLoc, diag::note_nontrivial_no_def_ctor)
-        << Kind << SubType.getUnqualifiedType();
-      if (CXXConstructorDecl *CD = findUserDeclaredCtor(SubRD))
-        S.Diag(CD->getLocation(), diag::note_user_declared_ctor);
-    } else if (!Selected)
-      S.Diag(SubobjLoc, diag::note_nontrivial_no_copy)
-        << Kind << SubType.getUnqualifiedType() << CSM << SubType;
-    else if (Selected->isUserProvided()) {
-      if (Kind == TSK_CompleteObject)
-        S.Diag(Selected->getLocation(), diag::note_nontrivial_user_provided)
-          << Kind << SubType.getUnqualifiedType() << CSM;
-      else {
-        S.Diag(SubobjLoc, diag::note_nontrivial_user_provided)
-          << Kind << SubType.getUnqualifiedType() << CSM;
-        S.Diag(Selected->getLocation(), diag::note_declared_at);
-      }
-    } else {
-      if (Kind != TSK_CompleteObject)
-        S.Diag(SubobjLoc, diag::note_nontrivial_subobject)
-          << Kind << SubType.getUnqualifiedType() << CSM;
-
-      // Explain why the defaulted or deleted special member isn't trivial.
-      S.SpecialMemberIsTrivial(Selected, CSM, Sema::TAH_IgnoreTrivialABI,
-                               Diagnose);
-    }
-  }
-
-  return false;
-}
-
-/// Check whether the members of a class type allow a special member to be
-/// trivial.
-static bool checkTrivialClassMembers(Sema &S, CXXRecordDecl *RD,
-                                     Sema::CXXSpecialMember CSM,
-                                     bool ConstArg,
-                                     Sema::TrivialABIHandling TAH,
-                                     bool Diagnose) {
-  for (const auto *FI : RD->fields()) {
-    if (FI->isInvalidDecl() || FI->isUnnamedBitfield())
-      continue;
-
-    QualType FieldType = S.Context.getBaseElementType(FI->getType());
-
-    // Pretend anonymous struct or union members are members of this class.
-    if (FI->isAnonymousStructOrUnion()) {
-      if (!checkTrivialClassMembers(S, FieldType->getAsCXXRecordDecl(),
-                                    CSM, ConstArg, TAH, Diagnose))
-        return false;
-      continue;
-    }
-
-    // C++11 [class.ctor]p5:
-    //   A default constructor is trivial if [...]
-    //    -- no non-static data member of its class has a
-    //       brace-or-equal-initializer
-    if (CSM == Sema::CXXDefaultConstructor && FI->hasInClassInitializer()) {
-      if (Diagnose)
-        S.Diag(FI->getLocation(), diag::note_nontrivial_in_class_init) << FI;
-      return false;
-    }
-
-    // Objective C ARC 4.3.5:
-    //   [...] nontrivally ownership-qualified types are [...] not trivially
-    //   default constructible, copy constructible, move constructible, copy
-    //   assignable, move assignable, or destructible [...]
-    if (FieldType.hasNonTrivialObjCLifetime()) {
-      if (Diagnose)
-        S.Diag(FI->getLocation(), diag::note_nontrivial_objc_ownership)
-          << RD << FieldType.getObjCLifetime();
-      return false;
-    }
-
-    bool ConstRHS = ConstArg && !FI->isMutable();
-    if (!checkTrivialSubobjectCall(S, FI->getLocation(), FieldType, ConstRHS,
-                                   CSM, TSK_Field, TAH, Diagnose))
-      return false;
-  }
-
-  return true;
-}
-
-/// Diagnose why the specified class does not have a trivial special member of
-/// the given kind.
-void Sema::DiagnoseNontrivial(const CXXRecordDecl *RD, CXXSpecialMember CSM) {
-  QualType Ty = Context.getRecordType(RD);
-
-  bool ConstArg = (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment);
-  checkTrivialSubobjectCall(*this, RD->getLocation(), Ty, ConstArg, CSM,
-                            TSK_CompleteObject, TAH_IgnoreTrivialABI,
-                            /*Diagnose*/true);
-}
-
-/// Determine whether a defaulted or deleted special member function is trivial,
-/// as specified in C++11 [class.ctor]p5, C++11 [class.copy]p12,
-/// C++11 [class.copy]p25, and C++11 [class.dtor]p5.
-bool Sema::SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
-                                  TrivialABIHandling TAH, bool Diagnose) {
-  assert(!MD->isUserProvided() && CSM != CXXInvalid && "not special enough");
-
-  CXXRecordDecl *RD = MD->getParent();
-
-  bool ConstArg = false;
-
-  // C++11 [class.copy]p12, p25: [DR1593]
-  //   A [special member] is trivial if [...] its parameter-type-list is
-  //   equivalent to the parameter-type-list of an implicit declaration [...]
-  switch (CSM) {
-  case CXXDefaultConstructor:
-  case CXXDestructor:
-    // Trivial default constructors and destructors cannot have parameters.
-    break;
-
-  case CXXCopyConstructor:
-  case CXXCopyAssignment: {
-    // Trivial copy operations always have const, non-volatile parameter types.
-    ConstArg = true;
-    const ParmVarDecl *Param0 = MD->getParamDecl(0);
-    const ReferenceType *RT = Param0->getType()->getAs<ReferenceType>();
-    if (!RT || RT->getPointeeType().getCVRQualifiers() != Qualifiers::Const) {
-      if (Diagnose)
-        Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
-          << Param0->getSourceRange() << Param0->getType()
-          << Context.getLValueReferenceType(
-               Context.getRecordType(RD).withConst());
-      return false;
-    }
-    break;
-  }
-
-  case CXXMoveConstructor:
-  case CXXMoveAssignment: {
-    // Trivial move operations always have non-cv-qualified parameters.
-    const ParmVarDecl *Param0 = MD->getParamDecl(0);
-    const RValueReferenceType *RT =
-      Param0->getType()->getAs<RValueReferenceType>();
-    if (!RT || RT->getPointeeType().getCVRQualifiers()) {
-      if (Diagnose)
-        Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
-          << Param0->getSourceRange() << Param0->getType()
-          << Context.getRValueReferenceType(Context.getRecordType(RD));
-      return false;
-    }
-    break;
-  }
-
-  case CXXInvalid:
-    llvm_unreachable("not a special member");
-  }
-
-  if (MD->getMinRequiredArguments() < MD->getNumParams()) {
-    if (Diagnose)
-      Diag(MD->getParamDecl(MD->getMinRequiredArguments())->getLocation(),
-           diag::note_nontrivial_default_arg)
-        << MD->getParamDecl(MD->getMinRequiredArguments())->getSourceRange();
-    return false;
-  }
-  if (MD->isVariadic()) {
-    if (Diagnose)
-      Diag(MD->getLocation(), diag::note_nontrivial_variadic);
-    return false;
-  }
-
-  // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
-  //   A copy/move [constructor or assignment operator] is trivial if
-  //    -- the [member] selected to copy/move each direct base class subobject
-  //       is trivial
-  //
-  // C++11 [class.copy]p12, C++11 [class.copy]p25:
-  //   A [default constructor or destructor] is trivial if
-  //    -- all the direct base classes have trivial [default constructors or
-  //       destructors]
-  for (const auto &BI : RD->bases())
-    if (!checkTrivialSubobjectCall(*this, BI.getBeginLoc(), BI.getType(),
-                                   ConstArg, CSM, TSK_BaseClass, TAH, Diagnose))
-      return false;
-
-  // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
-  //   A copy/move [constructor or assignment operator] for a class X is
-  //   trivial if
-  //    -- for each non-static data member of X that is of class type (or array
-  //       thereof), the constructor selected to copy/move that member is
-  //       trivial
-  //
-  // C++11 [class.copy]p12, C++11 [class.copy]p25:
-  //   A [default constructor or destructor] is trivial if
-  //    -- for all of the non-static data members of its class that are of class
-  //       type (or array thereof), each such class has a trivial [default
-  //       constructor or destructor]
-  if (!checkTrivialClassMembers(*this, RD, CSM, ConstArg, TAH, Diagnose))
-    return false;
-
-  // C++11 [class.dtor]p5:
-  //   A destructor is trivial if [...]
-  //    -- the destructor is not virtual
-  if (CSM == CXXDestructor && MD->isVirtual()) {
-    if (Diagnose)
-      Diag(MD->getLocation(), diag::note_nontrivial_virtual_dtor) << RD;
-    return false;
-  }
-
-  // C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25:
-  //   A [special member] for class X is trivial if [...]
-  //    -- class X has no virtual functions and no virtual base classes
-  if (CSM != CXXDestructor && MD->getParent()->isDynamicClass()) {
-    if (!Diagnose)
-      return false;
-
-    if (RD->getNumVBases()) {
-      // Check for virtual bases. We already know that the corresponding
-      // member in all bases is trivial, so vbases must all be direct.
-      CXXBaseSpecifier &BS = *RD->vbases_begin();
-      assert(BS.isVirtual());
-      Diag(BS.getBeginLoc(), diag::note_nontrivial_has_virtual) << RD << 1;
-      return false;
-    }
-
-    // Must have a virtual method.
-    for (const auto *MI : RD->methods()) {
-      if (MI->isVirtual()) {
-        SourceLocation MLoc = MI->getBeginLoc();
-        Diag(MLoc, diag::note_nontrivial_has_virtual) << RD << 0;
-        return false;
-      }
-    }
-
-    llvm_unreachable("dynamic class with no vbases and no virtual functions");
-  }
-
-  // Looks like it's trivial!
-  return true;
-}
-
-namespace {
-struct FindHiddenVirtualMethod {
-  Sema *S;
-  CXXMethodDecl *Method;
-  llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverridenAndUsingBaseMethods;
-  SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
-
-private:
-  /// Check whether any most overridden method from MD in Methods
-  static bool CheckMostOverridenMethods(
-      const CXXMethodDecl *MD,
-      const llvm::SmallPtrSetImpl<const CXXMethodDecl *> &Methods) {
-    if (MD->size_overridden_methods() == 0)
-      return Methods.count(MD->getCanonicalDecl());
-    for (const CXXMethodDecl *O : MD->overridden_methods())
-      if (CheckMostOverridenMethods(O, Methods))
-        return true;
-    return false;
-  }
-
-public:
-  /// Member lookup function that determines whether a given C++
-  /// method overloads virtual methods in a base class without overriding any,
-  /// to be used with CXXRecordDecl::lookupInBases().
-  bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
-    RecordDecl *BaseRecord =
-        Specifier->getType()->getAs<RecordType>()->getDecl();
-
-    DeclarationName Name = Method->getDeclName();
-    assert(Name.getNameKind() == DeclarationName::Identifier);
-
-    bool foundSameNameMethod = false;
-    SmallVector<CXXMethodDecl *, 8> overloadedMethods;
-    for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
-         Path.Decls = Path.Decls.slice(1)) {
-      NamedDecl *D = Path.Decls.front();
-      if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
-        MD = MD->getCanonicalDecl();
-        foundSameNameMethod = true;
-        // Interested only in hidden virtual methods.
-        if (!MD->isVirtual())
-          continue;
-        // If the method we are checking overrides a method from its base
-        // don't warn about the other overloaded methods. Clang deviates from
-        // GCC by only diagnosing overloads of inherited virtual functions that
-        // do not override any other virtual functions in the base. GCC's
-        // -Woverloaded-virtual diagnoses any derived function hiding a virtual
-        // function from a base class. These cases may be better served by a
-        // warning (not specific to virtual functions) on call sites when the
-        // call would select a different function from the base class, were it
-        // visible.
-        // See FIXME in test/SemaCXX/warn-overload-virtual.cpp for an example.
-        if (!S->IsOverload(Method, MD, false))
-          return true;
-        // Collect the overload only if its hidden.
-        if (!CheckMostOverridenMethods(MD, OverridenAndUsingBaseMethods))
-          overloadedMethods.push_back(MD);
-      }
-    }
-
-    if (foundSameNameMethod)
-      OverloadedMethods.append(overloadedMethods.begin(),
-                               overloadedMethods.end());
-    return foundSameNameMethod;
-  }
-};
-} // end anonymous namespace
-
-/// Add the most overriden methods from MD to Methods
-static void AddMostOverridenMethods(const CXXMethodDecl *MD,
-                        llvm::SmallPtrSetImpl<const CXXMethodDecl *>& Methods) {
-  if (MD->size_overridden_methods() == 0)
-    Methods.insert(MD->getCanonicalDecl());
-  else
-    for (const CXXMethodDecl *O : MD->overridden_methods())
-      AddMostOverridenMethods(O, Methods);
-}
-
-/// Check if a method overloads virtual methods in a base class without
-/// overriding any.
-void Sema::FindHiddenVirtualMethods(CXXMethodDecl *MD,
-                          SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
-  if (!MD->getDeclName().isIdentifier())
-    return;
-
-  CXXBasePaths Paths(/*FindAmbiguities=*/true, // true to look in all bases.
-                     /*bool RecordPaths=*/false,
-                     /*bool DetectVirtual=*/false);
-  FindHiddenVirtualMethod FHVM;
-  FHVM.Method = MD;
-  FHVM.S = this;
-
-  // Keep the base methods that were overridden or introduced in the subclass
-  // by 'using' in a set. A base method not in this set is hidden.
-  CXXRecordDecl *DC = MD->getParent();
-  DeclContext::lookup_result R = DC->lookup(MD->getDeclName());
-  for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E; ++I) {
-    NamedDecl *ND = *I;
-    if (UsingShadowDecl *shad = dyn_cast<UsingShadowDecl>(*I))
-      ND = shad->getTargetDecl();
-    if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
-      AddMostOverridenMethods(MD, FHVM.OverridenAndUsingBaseMethods);
-  }
-
-  if (DC->lookupInBases(FHVM, Paths))
-    OverloadedMethods = FHVM.OverloadedMethods;
-}
-
-void Sema::NoteHiddenVirtualMethods(CXXMethodDecl *MD,
-                          SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
-  for (unsigned i = 0, e = OverloadedMethods.size(); i != e; ++i) {
-    CXXMethodDecl *overloadedMD = OverloadedMethods[i];
-    PartialDiagnostic PD = PDiag(
-         diag::note_hidden_overloaded_virtual_declared_here) << overloadedMD;
-    HandleFunctionTypeMismatch(PD, MD->getType(), overloadedMD->getType());
-    Diag(overloadedMD->getLocation(), PD);
-  }
-}
-
-/// Diagnose methods which overload virtual methods in a base class
-/// without overriding any.
-void Sema::DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD) {
-  if (MD->isInvalidDecl())
-    return;
-
-  if (Diags.isIgnored(diag::warn_overloaded_virtual, MD->getLocation()))
-    return;
-
-  SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
-  FindHiddenVirtualMethods(MD, OverloadedMethods);
-  if (!OverloadedMethods.empty()) {
-    Diag(MD->getLocation(), diag::warn_overloaded_virtual)
-      << MD << (OverloadedMethods.size() > 1);
-
-    NoteHiddenVirtualMethods(MD, OverloadedMethods);
-  }
-}
-
-void Sema::checkIllFormedTrivialABIStruct(CXXRecordDecl &RD) {
-  auto PrintDiagAndRemoveAttr = [&]() {
-    // No diagnostics if this is a template instantiation.
-    if (!isTemplateInstantiation(RD.getTemplateSpecializationKind()))
-      Diag(RD.getAttr<TrivialABIAttr>()->getLocation(),
-           diag::ext_cannot_use_trivial_abi) << &RD;
-    RD.dropAttr<TrivialABIAttr>();
-  };
-
-  // Ill-formed if the struct has virtual functions.
-  if (RD.isPolymorphic()) {
-    PrintDiagAndRemoveAttr();
-    return;
-  }
-
-  for (const auto &B : RD.bases()) {
-    // Ill-formed if the base class is non-trivial for the purpose of calls or a
-    // virtual base.
-    if ((!B.getType()->isDependentType() &&
-         !B.getType()->getAsCXXRecordDecl()->canPassInRegisters()) ||
-        B.isVirtual()) {
-      PrintDiagAndRemoveAttr();
-      return;
-    }
-  }
-
-  for (const auto *FD : RD.fields()) {
-    // Ill-formed if the field is an ObjectiveC pointer or of a type that is
-    // non-trivial for the purpose of calls.
-    QualType FT = FD->getType();
-    if (FT.getObjCLifetime() == Qualifiers::OCL_Weak) {
-      PrintDiagAndRemoveAttr();
-      return;
-    }
-
-    if (const auto *RT = FT->getBaseElementTypeUnsafe()->getAs<RecordType>())
-      if (!RT->isDependentType() &&
-          !cast<CXXRecordDecl>(RT->getDecl())->canPassInRegisters()) {
-        PrintDiagAndRemoveAttr();
-        return;
-      }
-  }
-}
-
-void Sema::ActOnFinishCXXMemberSpecification(
-    Scope *S, SourceLocation RLoc, Decl *TagDecl, SourceLocation LBrac,
-    SourceLocation RBrac, const ParsedAttributesView &AttrList) {
-  if (!TagDecl)
-    return;
-
-  AdjustDeclIfTemplate(TagDecl);
-
-  for (const ParsedAttr &AL : AttrList) {
-    if (AL.getKind() != ParsedAttr::AT_Visibility)
-      continue;
-    AL.setInvalid();
-    Diag(AL.getLoc(), diag::warn_attribute_after_definition_ignored)
-        << AL.getName();
-  }
-
-  ActOnFields(S, RLoc, TagDecl, llvm::makeArrayRef(
-              // strict aliasing violation!
-              reinterpret_cast<Decl**>(FieldCollector->getCurFields()),
-              FieldCollector->getCurNumFields()), LBrac, RBrac, AttrList);
-
-  CheckCompletedCXXClass(cast<CXXRecordDecl>(TagDecl));
-}
-
-/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared
-/// special functions, such as the default constructor, copy
-/// constructor, or destructor, to the given C++ class (C++
-/// [special]p1).  This routine can only be executed just before the
-/// definition of the class is complete.
-void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) {
-  if (ClassDecl->needsImplicitDefaultConstructor()) {
-    ++ASTContext::NumImplicitDefaultConstructors;
-
-    if (ClassDecl->hasInheritedConstructor())
-      DeclareImplicitDefaultConstructor(ClassDecl);
-  }
-
-  if (ClassDecl->needsImplicitCopyConstructor()) {
-    ++ASTContext::NumImplicitCopyConstructors;
-
-    // If the properties or semantics of the copy constructor couldn't be
-    // determined while the class was being declared, force a declaration
-    // of it now.
-    if (ClassDecl->needsOverloadResolutionForCopyConstructor() ||
-        ClassDecl->hasInheritedConstructor())
-      DeclareImplicitCopyConstructor(ClassDecl);
-    // For the MS ABI we need to know whether the copy ctor is deleted. A
-    // prerequisite for deleting the implicit copy ctor is that the class has a
-    // move ctor or move assignment that is either user-declared or whose
-    // semantics are inherited from a subobject. FIXME: We should provide a more
-    // direct way for CodeGen to ask whether the constructor was deleted.
-    else if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
-             (ClassDecl->hasUserDeclaredMoveConstructor() ||
-              ClassDecl->needsOverloadResolutionForMoveConstructor() ||
-              ClassDecl->hasUserDeclaredMoveAssignment() ||
-              ClassDecl->needsOverloadResolutionForMoveAssignment()))
-      DeclareImplicitCopyConstructor(ClassDecl);
-  }
-
-  if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveConstructor()) {
-    ++ASTContext::NumImplicitMoveConstructors;
-
-    if (ClassDecl->needsOverloadResolutionForMoveConstructor() ||
-        ClassDecl->hasInheritedConstructor())
-      DeclareImplicitMoveConstructor(ClassDecl);
-  }
-
-  if (ClassDecl->needsImplicitCopyAssignment()) {
-    ++ASTContext::NumImplicitCopyAssignmentOperators;
-
-    // If we have a dynamic class, then the copy assignment operator may be
-    // virtual, so we have to declare it immediately. This ensures that, e.g.,
-    // it shows up in the right place in the vtable and that we diagnose
-    // problems with the implicit exception specification.
-    if (ClassDecl->isDynamicClass() ||
-        ClassDecl->needsOverloadResolutionForCopyAssignment() ||
-        ClassDecl->hasInheritedAssignment())
-      DeclareImplicitCopyAssignment(ClassDecl);
-  }
-
-  if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveAssignment()) {
-    ++ASTContext::NumImplicitMoveAssignmentOperators;
-
-    // Likewise for the move assignment operator.
-    if (ClassDecl->isDynamicClass() ||
-        ClassDecl->needsOverloadResolutionForMoveAssignment() ||
-        ClassDecl->hasInheritedAssignment())
-      DeclareImplicitMoveAssignment(ClassDecl);
-  }
-
-  if (ClassDecl->needsImplicitDestructor()) {
-    ++ASTContext::NumImplicitDestructors;
-
-    // If we have a dynamic class, then the destructor may be virtual, so we
-    // have to declare the destructor immediately. This ensures that, e.g., it
-    // shows up in the right place in the vtable and that we diagnose problems
-    // with the implicit exception specification.
-    if (ClassDecl->isDynamicClass() ||
-        ClassDecl->needsOverloadResolutionForDestructor())
-      DeclareImplicitDestructor(ClassDecl);
-  }
-}
-
-unsigned Sema::ActOnReenterTemplateScope(Scope *S, Decl *D) {
-  if (!D)
-    return 0;
-
-  // The order of template parameters is not important here. All names
-  // get added to the same scope.
-  SmallVector<TemplateParameterList *, 4> ParameterLists;
-
-  if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
-    D = TD->getTemplatedDecl();
-
-  if (auto *PSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(D))
-    ParameterLists.push_back(PSD->getTemplateParameters());
-
-  if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
-    for (unsigned i = 0; i < DD->getNumTemplateParameterLists(); ++i)
-      ParameterLists.push_back(DD->getTemplateParameterList(i));
-
-    if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
-      if (FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
-        ParameterLists.push_back(FTD->getTemplateParameters());
-    }
-  }
-
-  if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
-    for (unsigned i = 0; i < TD->getNumTemplateParameterLists(); ++i)
-      ParameterLists.push_back(TD->getTemplateParameterList(i));
-
-    if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) {
-      if (ClassTemplateDecl *CTD = RD->getDescribedClassTemplate())
-        ParameterLists.push_back(CTD->getTemplateParameters());
-    }
-  }
-
-  unsigned Count = 0;
-  for (TemplateParameterList *Params : ParameterLists) {
-    if (Params->size() > 0)
-      // Ignore explicit specializations; they don't contribute to the template
-      // depth.
-      ++Count;
-    for (NamedDecl *Param : *Params) {
-      if (Param->getDeclName()) {
-        S->AddDecl(Param);
-        IdResolver.AddDecl(Param);
-      }
-    }
-  }
-
-  return Count;
-}
-
-void Sema::ActOnStartDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
-  if (!RecordD) return;
-  AdjustDeclIfTemplate(RecordD);
-  CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordD);
-  PushDeclContext(S, Record);
-}
-
-void Sema::ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
-  if (!RecordD) return;
-  PopDeclContext();
-}
-
-/// This is used to implement the constant expression evaluation part of the
-/// attribute enable_if extension. There is nothing in standard C++ which would
-/// require reentering parameters.
-void Sema::ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param) {
-  if (!Param)
-    return;
-
-  S->AddDecl(Param);
-  if (Param->getDeclName())
-    IdResolver.AddDecl(Param);
-}
-
-/// ActOnStartDelayedCXXMethodDeclaration - We have completed
-/// parsing a top-level (non-nested) C++ class, and we are now
-/// parsing those parts of the given Method declaration that could
-/// not be parsed earlier (C++ [class.mem]p2), such as default
-/// arguments. This action should enter the scope of the given
-/// Method declaration as if we had just parsed the qualified method
-/// name. However, it should not bring the parameters into scope;
-/// that will be performed by ActOnDelayedCXXMethodParameter.
-void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
-}
-
-/// ActOnDelayedCXXMethodParameter - We've already started a delayed
-/// C++ method declaration. We're (re-)introducing the given
-/// function parameter into scope for use in parsing later parts of
-/// the method declaration. For example, we could see an
-/// ActOnParamDefaultArgument event for this parameter.
-void Sema::ActOnDelayedCXXMethodParameter(Scope *S, Decl *ParamD) {
-  if (!ParamD)
-    return;
-
-  ParmVarDecl *Param = cast<ParmVarDecl>(ParamD);
-
-  // If this parameter has an unparsed default argument, clear it out
-  // to make way for the parsed default argument.
-  if (Param->hasUnparsedDefaultArg())
-    Param->setDefaultArg(nullptr);
-
-  S->AddDecl(Param);
-  if (Param->getDeclName())
-    IdResolver.AddDecl(Param);
-}
-
-/// ActOnFinishDelayedCXXMethodDeclaration - We have finished
-/// processing the delayed method declaration for Method. The method
-/// declaration is now considered finished. There may be a separate
-/// ActOnStartOfFunctionDef action later (not necessarily
-/// immediately!) for this method, if it was also defined inside the
-/// class body.
-void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
-  if (!MethodD)
-    return;
-
-  AdjustDeclIfTemplate(MethodD);
-
-  FunctionDecl *Method = cast<FunctionDecl>(MethodD);
-
-  // Now that we have our default arguments, check the constructor
-  // again. It could produce additional diagnostics or affect whether
-  // the class has implicitly-declared destructors, among other
-  // things.
-  if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method))
-    CheckConstructor(Constructor);
-
-  // Check the default arguments, which we may have added.
-  if (!Method->isInvalidDecl())
-    CheckCXXDefaultArguments(Method);
-}
-
-/// CheckConstructorDeclarator - Called by ActOnDeclarator to check
-/// the well-formedness of the constructor declarator @p D with type @p
-/// R. If there are any errors in the declarator, this routine will
-/// emit diagnostics and set the invalid bit to true.  In any case, the type
-/// will be updated to reflect a well-formed type for the constructor and
-/// returned.
-QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R,
-                                          StorageClass &SC) {
-  bool isVirtual = D.getDeclSpec().isVirtualSpecified();
-
-  // C++ [class.ctor]p3:
-  //   A constructor shall not be virtual (10.3) or static (9.4). A
-  //   constructor can be invoked for a const, volatile or const
-  //   volatile object. A constructor shall not be declared const,
-  //   volatile, or const volatile (9.3.2).
-  if (isVirtual) {
-    if (!D.isInvalidType())
-      Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
-        << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc())
-        << SourceRange(D.getIdentifierLoc());
-    D.setInvalidType();
-  }
-  if (SC == SC_Static) {
-    if (!D.isInvalidType())
-      Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
-        << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
-        << SourceRange(D.getIdentifierLoc());
-    D.setInvalidType();
-    SC = SC_None;
-  }
-
-  if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
-    diagnoseIgnoredQualifiers(
-        diag::err_constructor_return_type, TypeQuals, SourceLocation(),
-        D.getDeclSpec().getConstSpecLoc(), D.getDeclSpec().getVolatileSpecLoc(),
-        D.getDeclSpec().getRestrictSpecLoc(),
-        D.getDeclSpec().getAtomicSpecLoc());
-    D.setInvalidType();
-  }
-
-  DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
-  if (FTI.hasMethodTypeQualifiers()) {
-    FTI.MethodQualifiers->forEachQualifier(
-        [&](DeclSpec::TQ TypeQual, StringRef QualName, SourceLocation SL) {
-          Diag(SL, diag::err_invalid_qualified_constructor)
-              << QualName << SourceRange(SL);
-        });
-    D.setInvalidType();
-  }
-
-  // C++0x [class.ctor]p4:
-  //   A constructor shall not be declared with a ref-qualifier.
-  if (FTI.hasRefQualifier()) {
-    Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_constructor)
-      << FTI.RefQualifierIsLValueRef
-      << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
-    D.setInvalidType();
-  }
-
-  // Rebuild the function type "R" without any type qualifiers (in
-  // case any of the errors above fired) and with "void" as the
-  // return type, since constructors don't have return types.
-  const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
-  if (Proto->getReturnType() == Context.VoidTy && !D.isInvalidType())
-    return R;
-
-  FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
-  EPI.TypeQuals = Qualifiers();
-  EPI.RefQualifier = RQ_None;
-
-  return Context.getFunctionType(Context.VoidTy, Proto->getParamTypes(), EPI);
-}
-
-/// CheckConstructor - Checks a fully-formed constructor for
-/// well-formedness, issuing any diagnostics required. Returns true if
-/// the constructor declarator is invalid.
-void Sema::CheckConstructor(CXXConstructorDecl *Constructor) {
-  CXXRecordDecl *ClassDecl
-    = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext());
-  if (!ClassDecl)
-    return Constructor->setInvalidDecl();
-
-  // C++ [class.copy]p3:
-  //   A declaration of a constructor for a class X is ill-formed if
-  //   its first parameter is of type (optionally cv-qualified) X and
-  //   either there are no other parameters or else all other
-  //   parameters have default arguments.
-  if (!Constructor->isInvalidDecl() &&
-      ((Constructor->getNumParams() == 1) ||
-       (Constructor->getNumParams() > 1 &&
-        Constructor->getParamDecl(1)->hasDefaultArg())) &&
-      Constructor->getTemplateSpecializationKind()
-                                              != TSK_ImplicitInstantiation) {
-    QualType ParamType = Constructor->getParamDecl(0)->getType();
-    QualType ClassTy = Context.getTagDeclType(ClassDecl);
-    if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) {
-      SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation();
-      const char *ConstRef
-        = Constructor->getParamDecl(0)->getIdentifier() ? "const &"
-                                                        : " const &";
-      Diag(ParamLoc, diag::err_constructor_byvalue_arg)
-        << FixItHint::CreateInsertion(ParamLoc, ConstRef);
-
-      // FIXME: Rather that making the constructor invalid, we should endeavor
-      // to fix the type.
-      Constructor->setInvalidDecl();
-    }
-  }
-}
-
-/// CheckDestructor - Checks a fully-formed destructor definition for
-/// well-formedness, issuing any diagnostics required.  Returns true
-/// on error.
-bool Sema::CheckDestructor(CXXDestructorDecl *Destructor) {
-  CXXRecordDecl *RD = Destructor->getParent();
-
-  if (!Destructor->getOperatorDelete() && Destructor->isVirtual()) {
-    SourceLocation Loc;
-
-    if (!Destructor->isImplicit())
-      Loc = Destructor->getLocation();
-    else
-      Loc = RD->getLocation();
-
-    // If we have a virtual destructor, look up the deallocation function
-    if (FunctionDecl *OperatorDelete =
-            FindDeallocationFunctionForDestructor(Loc, RD)) {
-      Expr *ThisArg = nullptr;
-
-      // If the notional 'delete this' expression requires a non-trivial
-      // conversion from 'this' to the type of a destroying operator delete's
-      // first parameter, perform that conversion now.
-      if (OperatorDelete->isDestroyingOperatorDelete()) {
-        QualType ParamType = OperatorDelete->getParamDecl(0)->getType();
-        if (!declaresSameEntity(ParamType->getAsCXXRecordDecl(), RD)) {
-          // C++ [class.dtor]p13:
-          //   ... as if for the expression 'delete this' appearing in a
-          //   non-virtual destructor of the destructor's class.
-          ContextRAII SwitchContext(*this, Destructor);
-          ExprResult This =
-              ActOnCXXThis(OperatorDelete->getParamDecl(0)->getLocation());
-          assert(!This.isInvalid() && "couldn't form 'this' expr in dtor?");
-          This = PerformImplicitConversion(This.get(), ParamType, AA_Passing);
-          if (This.isInvalid()) {
-            // FIXME: Register this as a context note so that it comes out
-            // in the right order.
-            Diag(Loc, diag::note_implicit_delete_this_in_destructor_here);
-            return true;
-          }
-          ThisArg = This.get();
-        }
-      }
-
-      DiagnoseUseOfDecl(OperatorDelete, Loc);
-      MarkFunctionReferenced(Loc, OperatorDelete);
-      Destructor->setOperatorDelete(OperatorDelete, ThisArg);
-    }
-  }
-
-  return false;
-}
-
-/// CheckDestructorDeclarator - Called by ActOnDeclarator to check
-/// the well-formednes of the destructor declarator @p D with type @p
-/// R. If there are any errors in the declarator, this routine will
-/// emit diagnostics and set the declarator to invalid.  Even if this happens,
-/// will be updated to reflect a well-formed type for the destructor and
-/// returned.
-QualType Sema::CheckDestructorDeclarator(Declarator &D, QualType R,
-                                         StorageClass& SC) {
-  // C++ [class.dtor]p1:
-  //   [...] A typedef-name that names a class is a class-name
-  //   (7.1.3); however, a typedef-name that names a class shall not
-  //   be used as the identifier in the declarator for a destructor
-  //   declaration.
-  QualType DeclaratorType = GetTypeFromParser(D.getName().DestructorName);
-  if (const TypedefType *TT = DeclaratorType->getAs<TypedefType>())
-    Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
-      << DeclaratorType << isa<TypeAliasDecl>(TT->getDecl());
-  else if (const TemplateSpecializationType *TST =
-             DeclaratorType->getAs<TemplateSpecializationType>())
-    if (TST->isTypeAlias())
-      Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
-        << DeclaratorType << 1;
-
-  // C++ [class.dtor]p2:
-  //   A destructor is used to destroy objects of its class type. A
-  //   destructor takes no parameters, and no return type can be
-  //   specified for it (not even void). The address of a destructor
-  //   shall not be taken. A destructor shall not be static. A
-  //   destructor can be invoked for a const, volatile or const
-  //   volatile object. A destructor shall not be declared const,
-  //   volatile or const volatile (9.3.2).
-  if (SC == SC_Static) {
-    if (!D.isInvalidType())
-      Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be)
-        << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
-        << SourceRange(D.getIdentifierLoc())
-        << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
-
-    SC = SC_None;
-  }
-  if (!D.isInvalidType()) {
-    // Destructors don't have return types, but the parser will
-    // happily parse something like:
-    //
-    //   class X {
-    //     float ~X();
-    //   };
-    //
-    // The return type will be eliminated later.
-    if (D.getDeclSpec().hasTypeSpecifier())
-      Diag(D.getIdentifierLoc(), diag::err_destructor_return_type)
-        << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
-        << SourceRange(D.getIdentifierLoc());
-    else if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
-      diagnoseIgnoredQualifiers(diag::err_destructor_return_type, TypeQuals,
-                                SourceLocation(),
-                                D.getDeclSpec().getConstSpecLoc(),
-                                D.getDeclSpec().getVolatileSpecLoc(),
-                                D.getDeclSpec().getRestrictSpecLoc(),
-                                D.getDeclSpec().getAtomicSpecLoc());
-      D.setInvalidType();
-    }
-  }
-
-  DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
-  if (FTI.hasMethodTypeQualifiers() && !D.isInvalidType()) {
-    FTI.MethodQualifiers->forEachQualifier(
-        [&](DeclSpec::TQ TypeQual, StringRef QualName, SourceLocation SL) {
-          Diag(SL, diag::err_invalid_qualified_destructor)
-              << QualName << SourceRange(SL);
-        });
-    D.setInvalidType();
-  }
-
-  // C++0x [class.dtor]p2:
-  //   A destructor shall not be declared with a ref-qualifier.
-  if (FTI.hasRefQualifier()) {
-    Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_destructor)
-      << FTI.RefQualifierIsLValueRef
-      << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
-    D.setInvalidType();
-  }
-
-  // Make sure we don't have any parameters.
-  if (FTIHasNonVoidParameters(FTI)) {
-    Diag(D.getIdentifierLoc(), diag::err_destructor_with_params);
-
-    // Delete the parameters.
-    FTI.freeParams();
-    D.setInvalidType();
-  }
-
-  // Make sure the destructor isn't variadic.
-  if (FTI.isVariadic) {
-    Diag(D.getIdentifierLoc(), diag::err_destructor_variadic);
-    D.setInvalidType();
-  }
-
-  // Rebuild the function type "R" without any type qualifiers or
-  // parameters (in case any of the errors above fired) and with
-  // "void" as the return type, since destructors don't have return
-  // types.
-  if (!D.isInvalidType())
-    return R;
-
-  const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
-  FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
-  EPI.Variadic = false;
-  EPI.TypeQuals = Qualifiers();
-  EPI.RefQualifier = RQ_None;
-  return Context.getFunctionType(Context.VoidTy, None, EPI);
-}
-
-static void extendLeft(SourceRange &R, SourceRange Before) {
-  if (Before.isInvalid())
-    return;
-  R.setBegin(Before.getBegin());
-  if (R.getEnd().isInvalid())
-    R.setEnd(Before.getEnd());
-}
-
-static void extendRight(SourceRange &R, SourceRange After) {
-  if (After.isInvalid())
-    return;
-  if (R.getBegin().isInvalid())
-    R.setBegin(After.getBegin());
-  R.setEnd(After.getEnd());
-}
-
-/// CheckConversionDeclarator - Called by ActOnDeclarator to check the
-/// well-formednes of the conversion function declarator @p D with
-/// type @p R. If there are any errors in the declarator, this routine
-/// will emit diagnostics and return true. Otherwise, it will return
-/// false. Either way, the type @p R will be updated to reflect a
-/// well-formed type for the conversion operator.
-void Sema::CheckConversionDeclarator(Declarator &D, QualType &R,
-                                     StorageClass& SC) {
-  // C++ [class.conv.fct]p1:
-  //   Neither parameter types nor return type can be specified. The
-  //   type of a conversion function (8.3.5) is "function taking no
-  //   parameter returning conversion-type-id."
-  if (SC == SC_Static) {
-    if (!D.isInvalidType())
-      Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member)
-        << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
-        << D.getName().getSourceRange();
-    D.setInvalidType();
-    SC = SC_None;
-  }
-
-  TypeSourceInfo *ConvTSI = nullptr;
-  QualType ConvType =
-      GetTypeFromParser(D.getName().ConversionFunctionId, &ConvTSI);
-
-  const DeclSpec &DS = D.getDeclSpec();
-  if (DS.hasTypeSpecifier() && !D.isInvalidType()) {
-    // Conversion functions don't have return types, but the parser will
-    // happily parse something like:
-    //
-    //   class X {
-    //     float operator bool();
-    //   };
-    //
-    // The return type will be changed later anyway.
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type)
-      << SourceRange(DS.getTypeSpecTypeLoc())
-      << SourceRange(D.getIdentifierLoc());
-    D.setInvalidType();
-  } else if (DS.getTypeQualifiers() && !D.isInvalidType()) {
-    // It's also plausible that the user writes type qualifiers in the wrong
-    // place, such as:
-    //   struct S { const operator int(); };
-    // FIXME: we could provide a fixit to move the qualifiers onto the
-    // conversion type.
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_with_complex_decl)
-        << SourceRange(D.getIdentifierLoc()) << 0;
-    D.setInvalidType();
-  }
-
-  const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
-
-  // Make sure we don't have any parameters.
-  if (Proto->getNumParams() > 0) {
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params);
-
-    // Delete the parameters.
-    D.getFunctionTypeInfo().freeParams();
-    D.setInvalidType();
-  } else if (Proto->isVariadic()) {
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic);
-    D.setInvalidType();
-  }
-
-  // Diagnose "&operator bool()" and other such nonsense.  This
-  // is actually a gcc extension which we don't support.
-  if (Proto->getReturnType() != ConvType) {
-    bool NeedsTypedef = false;
-    SourceRange Before, After;
-
-    // Walk the chunks and extract information on them for our diagnostic.
-    bool PastFunctionChunk = false;
-    for (auto &Chunk : D.type_objects()) {
-      switch (Chunk.Kind) {
-      case DeclaratorChunk::Function:
-        if (!PastFunctionChunk) {
-          if (Chunk.Fun.HasTrailingReturnType) {
-            TypeSourceInfo *TRT = nullptr;
-            GetTypeFromParser(Chunk.Fun.getTrailingReturnType(), &TRT);
-            if (TRT) extendRight(After, TRT->getTypeLoc().getSourceRange());
-          }
-          PastFunctionChunk = true;
-          break;
-        }
-        LLVM_FALLTHROUGH;
-      case DeclaratorChunk::Array:
-        NeedsTypedef = true;
-        extendRight(After, Chunk.getSourceRange());
-        break;
-
-      case DeclaratorChunk::Pointer:
-      case DeclaratorChunk::BlockPointer:
-      case DeclaratorChunk::Reference:
-      case DeclaratorChunk::MemberPointer:
-      case DeclaratorChunk::Pipe:
-        extendLeft(Before, Chunk.getSourceRange());
-        break;
-
-      case DeclaratorChunk::Paren:
-        extendLeft(Before, Chunk.Loc);
-        extendRight(After, Chunk.EndLoc);
-        break;
-      }
-    }
-
-    SourceLocation Loc = Before.isValid() ? Before.getBegin() :
-                         After.isValid()  ? After.getBegin() :
-                                            D.getIdentifierLoc();
-    auto &&DB = Diag(Loc, diag::err_conv_function_with_complex_decl);
-    DB << Before << After;
-
-    if (!NeedsTypedef) {
-      DB << /*don't need a typedef*/0;
-
-      // If we can provide a correct fix-it hint, do so.
-      if (After.isInvalid() && ConvTSI) {
-        SourceLocation InsertLoc =
-            getLocForEndOfToken(ConvTSI->getTypeLoc().getEndLoc());
-        DB << FixItHint::CreateInsertion(InsertLoc, " ")
-           << FixItHint::CreateInsertionFromRange(
-                  InsertLoc, CharSourceRange::getTokenRange(Before))
-           << FixItHint::CreateRemoval(Before);
-      }
-    } else if (!Proto->getReturnType()->isDependentType()) {
-      DB << /*typedef*/1 << Proto->getReturnType();
-    } else if (getLangOpts().CPlusPlus11) {
-      DB << /*alias template*/2 << Proto->getReturnType();
-    } else {
-      DB << /*might not be fixable*/3;
-    }
-
-    // Recover by incorporating the other type chunks into the result type.
-    // Note, this does *not* change the name of the function. This is compatible
-    // with the GCC extension:
-    //   struct S { &operator int(); } s;
-    //   int &r = s.operator int(); // ok in GCC
-    //   S::operator int&() {} // error in GCC, function name is 'operator int'.
-    ConvType = Proto->getReturnType();
-  }
-
-  // C++ [class.conv.fct]p4:
-  //   The conversion-type-id shall not represent a function type nor
-  //   an array type.
-  if (ConvType->isArrayType()) {
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array);
-    ConvType = Context.getPointerType(ConvType);
-    D.setInvalidType();
-  } else if (ConvType->isFunctionType()) {
-    Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function);
-    ConvType = Context.getPointerType(ConvType);
-    D.setInvalidType();
-  }
-
-  // Rebuild the function type "R" without any parameters (in case any
-  // of the errors above fired) and with the conversion type as the
-  // return type.
-  if (D.isInvalidType())
-    R = Context.getFunctionType(ConvType, None, Proto->getExtProtoInfo());
-
-  // C++0x explicit conversion operators.
-  if (DS.isExplicitSpecified())
-    Diag(DS.getExplicitSpecLoc(),
-         getLangOpts().CPlusPlus11
-             ? diag::warn_cxx98_compat_explicit_conversion_functions
-             : diag::ext_explicit_conversion_functions)
-        << SourceRange(DS.getExplicitSpecLoc());
-}
-
-/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete
-/// the declaration of the given C++ conversion function. This routine
-/// is responsible for recording the conversion function in the C++
-/// class, if possible.
-Decl *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) {
-  assert(Conversion && "Expected to receive a conversion function declaration");
-
-  CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext());
-
-  // Make sure we aren't redeclaring the conversion function.
-  QualType ConvType = Context.getCanonicalType(Conversion->getConversionType());
-
-  // C++ [class.conv.fct]p1:
-  //   [...] A conversion function is never used to convert a
-  //   (possibly cv-qualified) object to the (possibly cv-qualified)
-  //   same object type (or a reference to it), to a (possibly
-  //   cv-qualified) base class of that type (or a reference to it),
-  //   or to (possibly cv-qualified) void.
-  // FIXME: Suppress this warning if the conversion function ends up being a
-  // virtual function that overrides a virtual function in a base class.
-  QualType ClassType
-    = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
-  if (const ReferenceType *ConvTypeRef = ConvType->getAs<ReferenceType>())
-    ConvType = ConvTypeRef->getPointeeType();
-  if (Conversion->getTemplateSpecializationKind() != TSK_Undeclared &&
-      Conversion->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
-    /* Suppress diagnostics for instantiations. */;
-  else if (ConvType->isRecordType()) {
-    ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType();
-    if (ConvType == ClassType)
-      Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used)
-        << ClassType;
-    else if (IsDerivedFrom(Conversion->getLocation(), ClassType, ConvType))
-      Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used)
-        <<  ClassType << ConvType;
-  } else if (ConvType->isVoidType()) {
-    Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used)
-      << ClassType << ConvType;
-  }
-
-  if (FunctionTemplateDecl *ConversionTemplate
-                                = Conversion->getDescribedFunctionTemplate())
-    return ConversionTemplate;
-
-  return Conversion;
-}
-
-namespace {
-/// Utility class to accumulate and print a diagnostic listing the invalid
-/// specifier(s) on a declaration.
-struct BadSpecifierDiagnoser {
-  BadSpecifierDiagnoser(Sema &S, SourceLocation Loc, unsigned DiagID)
-      : S(S), Diagnostic(S.Diag(Loc, DiagID)) {}
-  ~BadSpecifierDiagnoser() {
-    Diagnostic << Specifiers;
-  }
-
-  template<typename T> void check(SourceLocation SpecLoc, T Spec) {
-    return check(SpecLoc, DeclSpec::getSpecifierName(Spec));
-  }
-  void check(SourceLocation SpecLoc, DeclSpec::TST Spec) {
-    return check(SpecLoc,
-                 DeclSpec::getSpecifierName(Spec, S.getPrintingPolicy()));
-  }
-  void check(SourceLocation SpecLoc, const char *Spec) {
-    if (SpecLoc.isInvalid()) return;
-    Diagnostic << SourceRange(SpecLoc, SpecLoc);
-    if (!Specifiers.empty()) Specifiers += " ";
-    Specifiers += Spec;
-  }
-
-  Sema &S;
-  Sema::SemaDiagnosticBuilder Diagnostic;
-  std::string Specifiers;
-};
-}
-
-/// Check the validity of a declarator that we parsed for a deduction-guide.
-/// These aren't actually declarators in the grammar, so we need to check that
-/// the user didn't specify any pieces that are not part of the deduction-guide
-/// grammar.
-void Sema::CheckDeductionGuideDeclarator(Declarator &D, QualType &R,
-                                         StorageClass &SC) {
-  TemplateName GuidedTemplate = D.getName().TemplateName.get().get();
-  TemplateDecl *GuidedTemplateDecl = GuidedTemplate.getAsTemplateDecl();
-  assert(GuidedTemplateDecl && "missing template decl for deduction guide");
-
-  // C++ [temp.deduct.guide]p3:
-  //   A deduction-gide shall be declared in the same scope as the
-  //   corresponding class template.
-  if (!CurContext->getRedeclContext()->Equals(
-          GuidedTemplateDecl->getDeclContext()->getRedeclContext())) {
-    Diag(D.getIdentifierLoc(), diag::err_deduction_guide_wrong_scope)
-      << GuidedTemplateDecl;
-    Diag(GuidedTemplateDecl->getLocation(), diag::note_template_decl_here);
-  }
-
-  auto &DS = D.getMutableDeclSpec();
-  // We leave 'friend' and 'virtual' to be rejected in the normal way.
-  if (DS.hasTypeSpecifier() || DS.getTypeQualifiers() ||
-      DS.getStorageClassSpecLoc().isValid() || DS.isInlineSpecified() ||
-      DS.isNoreturnSpecified() || DS.isConstexprSpecified()) {
-    BadSpecifierDiagnoser Diagnoser(
-        *this, D.getIdentifierLoc(),
-        diag::err_deduction_guide_invalid_specifier);
-
-    Diagnoser.check(DS.getStorageClassSpecLoc(), DS.getStorageClassSpec());
-    DS.ClearStorageClassSpecs();
-    SC = SC_None;
-
-    // 'explicit' is permitted.
-    Diagnoser.check(DS.getInlineSpecLoc(), "inline");
-    Diagnoser.check(DS.getNoreturnSpecLoc(), "_Noreturn");
-    Diagnoser.check(DS.getConstexprSpecLoc(), "constexpr");
-    DS.ClearConstexprSpec();
-
-    Diagnoser.check(DS.getConstSpecLoc(), "const");
-    Diagnoser.check(DS.getRestrictSpecLoc(), "__restrict");
-    Diagnoser.check(DS.getVolatileSpecLoc(), "volatile");
-    Diagnoser.check(DS.getAtomicSpecLoc(), "_Atomic");
-    Diagnoser.check(DS.getUnalignedSpecLoc(), "__unaligned");
-    DS.ClearTypeQualifiers();
-
-    Diagnoser.check(DS.getTypeSpecComplexLoc(), DS.getTypeSpecComplex());
-    Diagnoser.check(DS.getTypeSpecSignLoc(), DS.getTypeSpecSign());
-    Diagnoser.check(DS.getTypeSpecWidthLoc(), DS.getTypeSpecWidth());
-    Diagnoser.check(DS.getTypeSpecTypeLoc(), DS.getTypeSpecType());
-    DS.ClearTypeSpecType();
-  }
-
-  if (D.isInvalidType())
-    return;
-
-  // Check the declarator is simple enough.
-  bool FoundFunction = false;
-  for (const DeclaratorChunk &Chunk : llvm::reverse(D.type_objects())) {
-    if (Chunk.Kind == DeclaratorChunk::Paren)
-      continue;
-    if (Chunk.Kind != DeclaratorChunk::Function || FoundFunction) {
-      Diag(D.getDeclSpec().getBeginLoc(),
-           diag::err_deduction_guide_with_complex_decl)
-          << D.getSourceRange();
-      break;
-    }
-    if (!Chunk.Fun.hasTrailingReturnType()) {
-      Diag(D.getName().getBeginLoc(),
-           diag::err_deduction_guide_no_trailing_return_type);
-      break;
-    }
-
-    // Check that the return type is written as a specialization of
-    // the template specified as the deduction-guide's name.
-    ParsedType TrailingReturnType = Chunk.Fun.getTrailingReturnType();
-    TypeSourceInfo *TSI = nullptr;
-    QualType RetTy = GetTypeFromParser(TrailingReturnType, &TSI);
-    assert(TSI && "deduction guide has valid type but invalid return type?");
-    bool AcceptableReturnType = false;
-    bool MightInstantiateToSpecialization = false;
-    if (auto RetTST =
-            TSI->getTypeLoc().getAs<TemplateSpecializationTypeLoc>()) {
-      TemplateName SpecifiedName = RetTST.getTypePtr()->getTemplateName();
-      bool TemplateMatches =
-          Context.hasSameTemplateName(SpecifiedName, GuidedTemplate);
-      if (SpecifiedName.getKind() == TemplateName::Template && TemplateMatches)
-        AcceptableReturnType = true;
-      else {
-        // This could still instantiate to the right type, unless we know it
-        // names the wrong class template.
-        auto *TD = SpecifiedName.getAsTemplateDecl();
-        MightInstantiateToSpecialization = !(TD && isa<ClassTemplateDecl>(TD) &&
-                                             !TemplateMatches);
-      }
-    } else if (!RetTy.hasQualifiers() && RetTy->isDependentType()) {
-      MightInstantiateToSpecialization = true;
-    }
-
-    if (!AcceptableReturnType) {
-      Diag(TSI->getTypeLoc().getBeginLoc(),
-           diag::err_deduction_guide_bad_trailing_return_type)
-          << GuidedTemplate << TSI->getType()
-          << MightInstantiateToSpecialization
-          << TSI->getTypeLoc().getSourceRange();
-    }
-
-    // Keep going to check that we don't have any inner declarator pieces (we
-    // could still have a function returning a pointer to a function).
-    FoundFunction = true;
-  }
-
-  if (D.isFunctionDefinition())
-    Diag(D.getIdentifierLoc(), diag::err_deduction_guide_defines_function);
-}
-
-//===----------------------------------------------------------------------===//
-// Namespace Handling
-//===----------------------------------------------------------------------===//
-
-/// Diagnose a mismatch in 'inline' qualifiers when a namespace is
-/// reopened.
-static void DiagnoseNamespaceInlineMismatch(Sema &S, SourceLocation KeywordLoc,
-                                            SourceLocation Loc,
-                                            IdentifierInfo *II, bool *IsInline,
-                                            NamespaceDecl *PrevNS) {
-  assert(*IsInline != PrevNS->isInline());
-
-  // HACK: Work around a bug in libstdc++4.6's <atomic>, where
-  // std::__atomic[0,1,2] are defined as non-inline namespaces, then reopened as
-  // inline namespaces, with the intention of bringing names into namespace std.
-  //
-  // We support this just well enough to get that case working; this is not
-  // sufficient to support reopening namespaces as inline in general.
-  if (*IsInline && II && II->getName().startswith("__atomic") &&
-      S.getSourceManager().isInSystemHeader(Loc)) {
-    // Mark all prior declarations of the namespace as inline.
-    for (NamespaceDecl *NS = PrevNS->getMostRecentDecl(); NS;
-         NS = NS->getPreviousDecl())
-      NS->setInline(*IsInline);
-    // Patch up the lookup table for the containing namespace. This isn't really
-    // correct, but it's good enough for this particular case.
-    for (auto *I : PrevNS->decls())
-      if (auto *ND = dyn_cast<NamedDecl>(I))
-        PrevNS->getParent()->makeDeclVisibleInContext(ND);
-    return;
-  }
-
-  if (PrevNS->isInline())
-    // The user probably just forgot the 'inline', so suggest that it
-    // be added back.
-    S.Diag(Loc, diag::warn_inline_namespace_reopened_noninline)
-      << FixItHint::CreateInsertion(KeywordLoc, "inline ");
-  else
-    S.Diag(Loc, diag::err_inline_namespace_mismatch);
-
-  S.Diag(PrevNS->getLocation(), diag::note_previous_definition);
-  *IsInline = PrevNS->isInline();
-}
-
-/// ActOnStartNamespaceDef - This is called at the start of a namespace
-/// definition.
-Decl *Sema::ActOnStartNamespaceDef(
-    Scope *NamespcScope, SourceLocation InlineLoc, SourceLocation NamespaceLoc,
-    SourceLocation IdentLoc, IdentifierInfo *II, SourceLocation LBrace,
-    const ParsedAttributesView &AttrList, UsingDirectiveDecl *&UD) {
-  SourceLocation StartLoc = InlineLoc.isValid() ? InlineLoc : NamespaceLoc;
-  // For anonymous namespace, take the location of the left brace.
-  SourceLocation Loc = II ? IdentLoc : LBrace;
-  bool IsInline = InlineLoc.isValid();
-  bool IsInvalid = false;
-  bool IsStd = false;
-  bool AddToKnown = false;
-  Scope *DeclRegionScope = NamespcScope->getParent();
-
-  NamespaceDecl *PrevNS = nullptr;
-  if (II) {
-    // C++ [namespace.def]p2:
-    //   The identifier in an original-namespace-definition shall not
-    //   have been previously defined in the declarative region in
-    //   which the original-namespace-definition appears. The
-    //   identifier in an original-namespace-definition is the name of
-    //   the namespace. Subsequently in that declarative region, it is
-    //   treated as an original-namespace-name.
-    //
-    // Since namespace names are unique in their scope, and we don't
-    // look through using directives, just look for any ordinary names
-    // as if by qualified name lookup.
-    LookupResult R(*this, II, IdentLoc, LookupOrdinaryName,
-                   ForExternalRedeclaration);
-    LookupQualifiedName(R, CurContext->getRedeclContext());
-    NamedDecl *PrevDecl =
-        R.isSingleResult() ? R.getRepresentativeDecl() : nullptr;
-    PrevNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl);
-
-    if (PrevNS) {
-      // This is an extended namespace definition.
-      if (IsInline != PrevNS->isInline())
-        DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, Loc, II,
-                                        &IsInline, PrevNS);
-    } else if (PrevDecl) {
-      // This is an invalid name redefinition.
-      Diag(Loc, diag::err_redefinition_different_kind)
-        << II;
-      Diag(PrevDecl->getLocation(), diag::note_previous_definition);
-      IsInvalid = true;
-      // Continue on to push Namespc as current DeclContext and return it.
-    } else if (II->isStr("std") &&
-               CurContext->getRedeclContext()->isTranslationUnit()) {
-      // This is the first "real" definition of the namespace "std", so update
-      // our cache of the "std" namespace to point at this definition.
-      PrevNS = getStdNamespace();
-      IsStd = true;
-      AddToKnown = !IsInline;
-    } else {
-      // We've seen this namespace for the first time.
-      AddToKnown = !IsInline;
-    }
-  } else {
-    // Anonymous namespaces.
-
-    // Determine whether the parent already has an anonymous namespace.
-    DeclContext *Parent = CurContext->getRedeclContext();
-    if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
-      PrevNS = TU->getAnonymousNamespace();
-    } else {
-      NamespaceDecl *ND = cast<NamespaceDecl>(Parent);
-      PrevNS = ND->getAnonymousNamespace();
-    }
-
-    if (PrevNS && IsInline != PrevNS->isInline())
-      DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, NamespaceLoc, II,
-                                      &IsInline, PrevNS);
-  }
-
-  NamespaceDecl *Namespc = NamespaceDecl::Create(Context, CurContext, IsInline,
-                                                 StartLoc, Loc, II, PrevNS);
-  if (IsInvalid)
-    Namespc->setInvalidDecl();
-
-  ProcessDeclAttributeList(DeclRegionScope, Namespc, AttrList);
-  AddPragmaAttributes(DeclRegionScope, Namespc);
-
-  // FIXME: Should we be merging attributes?
-  if (const VisibilityAttr *Attr = Namespc->getAttr<VisibilityAttr>())
-    PushNamespaceVisibilityAttr(Attr, Loc);
-
-  if (IsStd)
-    StdNamespace = Namespc;
-  if (AddToKnown)
-    KnownNamespaces[Namespc] = false;
-
-  if (II) {
-    PushOnScopeChains(Namespc, DeclRegionScope);
-  } else {
-    // Link the anonymous namespace into its parent.
-    DeclContext *Parent = CurContext->getRedeclContext();
-    if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
-      TU->setAnonymousNamespace(Namespc);
-    } else {
-      cast<NamespaceDecl>(Parent)->setAnonymousNamespace(Namespc);
-    }
-
-    CurContext->addDecl(Namespc);
-
-    // C++ [namespace.unnamed]p1.  An unnamed-namespace-definition
-    //   behaves as if it were replaced by
-    //     namespace unique { /* empty body */ }
-    //     using namespace unique;
-    //     namespace unique { namespace-body }
-    //   where all occurrences of 'unique' in a translation unit are
-    //   replaced by the same identifier and this identifier differs
-    //   from all other identifiers in the entire program.
-
-    // We just create the namespace with an empty name and then add an
-    // implicit using declaration, just like the standard suggests.
-    //
-    // CodeGen enforces the "universally unique" aspect by giving all
-    // declarations semantically contained within an anonymous
-    // namespace internal linkage.
-
-    if (!PrevNS) {
-      UD = UsingDirectiveDecl::Create(Context, Parent,
-                                      /* 'using' */ LBrace,
-                                      /* 'namespace' */ SourceLocation(),
-                                      /* qualifier */ NestedNameSpecifierLoc(),
-                                      /* identifier */ SourceLocation(),
-                                      Namespc,
-                                      /* Ancestor */ Parent);
-      UD->setImplicit();
-      Parent->addDecl(UD);
-    }
-  }
-
-  ActOnDocumentableDecl(Namespc);
-
-  // Although we could have an invalid decl (i.e. the namespace name is a
-  // redefinition), push it as current DeclContext and try to continue parsing.
-  // FIXME: We should be able to push Namespc here, so that the each DeclContext
-  // for the namespace has the declarations that showed up in that particular
-  // namespace definition.
-  PushDeclContext(NamespcScope, Namespc);
-  return Namespc;
-}
-
-/// getNamespaceDecl - Returns the namespace a decl represents. If the decl
-/// is a namespace alias, returns the namespace it points to.
-static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) {
-  if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D))
-    return AD->getNamespace();
-  return dyn_cast_or_null<NamespaceDecl>(D);
-}
-
-/// ActOnFinishNamespaceDef - This callback is called after a namespace is
-/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef.
-void Sema::ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace) {
-  NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl);
-  assert(Namespc && "Invalid parameter, expected NamespaceDecl");
-  Namespc->setRBraceLoc(RBrace);
-  PopDeclContext();
-  if (Namespc->hasAttr<VisibilityAttr>())
-    PopPragmaVisibility(true, RBrace);
-}
-
-CXXRecordDecl *Sema::getStdBadAlloc() const {
-  return cast_or_null<CXXRecordDecl>(
-                                  StdBadAlloc.get(Context.getExternalSource()));
-}
-
-EnumDecl *Sema::getStdAlignValT() const {
-  return cast_or_null<EnumDecl>(StdAlignValT.get(Context.getExternalSource()));
-}
-
-NamespaceDecl *Sema::getStdNamespace() const {
-  return cast_or_null<NamespaceDecl>(
-                                 StdNamespace.get(Context.getExternalSource()));
-}
-
-NamespaceDecl *Sema::lookupStdExperimentalNamespace() {
-  if (!StdExperimentalNamespaceCache) {
-    if (auto Std = getStdNamespace()) {
-      LookupResult Result(*this, &PP.getIdentifierTable().get("experimental"),
-                          SourceLocation(), LookupNamespaceName);
-      if (!LookupQualifiedName(Result, Std) ||
-          !(StdExperimentalNamespaceCache =
-                Result.getAsSingle<NamespaceDecl>()))
-        Result.suppressDiagnostics();
-    }
-  }
-  return StdExperimentalNamespaceCache;
-}
-
-namespace {
-
-enum UnsupportedSTLSelect {
-  USS_InvalidMember,
-  USS_MissingMember,
-  USS_NonTrivial,
-  USS_Other
-};
-
-struct InvalidSTLDiagnoser {
-  Sema &S;
-  SourceLocation Loc;
-  QualType TyForDiags;
-
-  QualType operator()(UnsupportedSTLSelect Sel = USS_Other, StringRef Name = "",
-                      const VarDecl *VD = nullptr) {
-    {
-      auto D = S.Diag(Loc, diag::err_std_compare_type_not_supported)
-               << TyForDiags << ((int)Sel);
-      if (Sel == USS_InvalidMember || Sel == USS_MissingMember) {
-        assert(!Name.empty());
-        D << Name;
-      }
-    }
-    if (Sel == USS_InvalidMember) {
-      S.Diag(VD->getLocation(), diag::note_var_declared_here)
-          << VD << VD->getSourceRange();
-    }
-    return QualType();
-  }
-};
-} // namespace
-
-QualType Sema::CheckComparisonCategoryType(ComparisonCategoryType Kind,
-                                           SourceLocation Loc) {
-  assert(getLangOpts().CPlusPlus &&
-         "Looking for comparison category type outside of C++.");
-
-  // Check if we've already successfully checked the comparison category type
-  // before. If so, skip checking it again.
-  ComparisonCategoryInfo *Info = Context.CompCategories.lookupInfo(Kind);
-  if (Info && FullyCheckedComparisonCategories[static_cast<unsigned>(Kind)])
-    return Info->getType();
-
-  // If lookup failed
-  if (!Info) {
-    std::string NameForDiags = "std::";
-    NameForDiags += ComparisonCategories::getCategoryString(Kind);
-    Diag(Loc, diag::err_implied_comparison_category_type_not_found)
-        << NameForDiags;
-    return QualType();
-  }
-
-  assert(Info->Kind == Kind);
-  assert(Info->Record);
-
-  // Update the Record decl in case we encountered a forward declaration on our
-  // first pass. FIXME: This is a bit of a hack.
-  if (Info->Record->hasDefinition())
-    Info->Record = Info->Record->getDefinition();
-
-  // Use an elaborated type for diagnostics which has a name containing the
-  // prepended 'std' namespace but not any inline namespace names.
-  QualType TyForDiags = [&]() {
-    auto *NNS =
-        NestedNameSpecifier::Create(Context, nullptr, getStdNamespace());
-    return Context.getElaboratedType(ETK_None, NNS, Info->getType());
-  }();
-
-  if (RequireCompleteType(Loc, TyForDiags, diag::err_incomplete_type))
-    return QualType();
-
-  InvalidSTLDiagnoser UnsupportedSTLError{*this, Loc, TyForDiags};
-
-  if (!Info->Record->isTriviallyCopyable())
-    return UnsupportedSTLError(USS_NonTrivial);
-
-  for (const CXXBaseSpecifier &BaseSpec : Info->Record->bases()) {
-    CXXRecordDecl *Base = BaseSpec.getType()->getAsCXXRecordDecl();
-    // Tolerate empty base classes.
-    if (Base->isEmpty())
-      continue;
-    // Reject STL implementations which have at least one non-empty base.
-    return UnsupportedSTLError();
-  }
-
-  // Check that the STL has implemented the types using a single integer field.
-  // This expectation allows better codegen for builtin operators. We require:
-  //   (1) The class has exactly one field.
-  //   (2) The field is an integral or enumeration type.
-  auto FIt = Info->Record->field_begin(), FEnd = Info->Record->field_end();
-  if (std::distance(FIt, FEnd) != 1 ||
-      !FIt->getType()->isIntegralOrEnumerationType()) {
-    return UnsupportedSTLError();
-  }
-
-  // Build each of the require values and store them in Info.
-  for (ComparisonCategoryResult CCR :
-       ComparisonCategories::getPossibleResultsForType(Kind)) {
-    StringRef MemName = ComparisonCategories::getResultString(CCR);
-    ComparisonCategoryInfo::ValueInfo *ValInfo = Info->lookupValueInfo(CCR);
-
-    if (!ValInfo)
-      return UnsupportedSTLError(USS_MissingMember, MemName);
-
-    VarDecl *VD = ValInfo->VD;
-    assert(VD && "should not be null!");
-
-    // Attempt to diagnose reasons why the STL definition of this type
-    // might be foobar, including it failing to be a constant expression.
-    // TODO Handle more ways the lookup or result can be invalid.
-    if (!VD->isStaticDataMember() || !VD->isConstexpr() || !VD->hasInit() ||
-        !VD->checkInitIsICE())
-      return UnsupportedSTLError(USS_InvalidMember, MemName, VD);
-
-    // Attempt to evaluate the var decl as a constant expression and extract
-    // the value of its first field as a ICE. If this fails, the STL
-    // implementation is not supported.
-    if (!ValInfo->hasValidIntValue())
-      return UnsupportedSTLError();
-
-    MarkVariableReferenced(Loc, VD);
-  }
-
-  // We've successfully built the required types and expressions. Update
-  // the cache and return the newly cached value.
-  FullyCheckedComparisonCategories[static_cast<unsigned>(Kind)] = true;
-  return Info->getType();
-}
-
-/// Retrieve the special "std" namespace, which may require us to
-/// implicitly define the namespace.
-NamespaceDecl *Sema::getOrCreateStdNamespace() {
-  if (!StdNamespace) {
-    // The "std" namespace has not yet been defined, so build one implicitly.
-    StdNamespace = NamespaceDecl::Create(Context,
-                                         Context.getTranslationUnitDecl(),
-                                         /*Inline=*/false,
-                                         SourceLocation(), SourceLocation(),
-                                         &PP.getIdentifierTable().get("std"),
-                                         /*PrevDecl=*/nullptr);
-    getStdNamespace()->setImplicit(true);
-  }
-
-  return getStdNamespace();
-}
-
-bool Sema::isStdInitializerList(QualType Ty, QualType *Element) {
-  assert(getLangOpts().CPlusPlus &&
-         "Looking for std::initializer_list outside of C++.");
-
-  // We're looking for implicit instantiations of
-  // template <typename E> class std::initializer_list.
-
-  if (!StdNamespace) // If we haven't seen namespace std yet, this can't be it.
-    return false;
-
-  ClassTemplateDecl *Template = nullptr;
-  const TemplateArgument *Arguments = nullptr;
-
-  if (const RecordType *RT = Ty->getAs<RecordType>()) {
-
-    ClassTemplateSpecializationDecl *Specialization =
-        dyn_cast<ClassTemplateSpecializationDecl>(RT->getDecl());
-    if (!Specialization)
-      return false;
-
-    Template = Specialization->getSpecializedTemplate();
-    Arguments = Specialization->getTemplateArgs().data();
-  } else if (const TemplateSpecializationType *TST =
-                 Ty->getAs<TemplateSpecializationType>()) {
-    Template = dyn_cast_or_null<ClassTemplateDecl>(
-        TST->getTemplateName().getAsTemplateDecl());
-    Arguments = TST->getArgs();
-  }
-  if (!Template)
-    return false;
-
-  if (!StdInitializerList) {
-    // Haven't recognized std::initializer_list yet, maybe this is it.
-    CXXRecordDecl *TemplateClass = Template->getTemplatedDecl();
-    if (TemplateClass->getIdentifier() !=
-            &PP.getIdentifierTable().get("initializer_list") ||
-        !getStdNamespace()->InEnclosingNamespaceSetOf(
-            TemplateClass->getDeclContext()))
-      return false;
-    // This is a template called std::initializer_list, but is it the right
-    // template?
-    TemplateParameterList *Params = Template->getTemplateParameters();
-    if (Params->getMinRequiredArguments() != 1)
-      return false;
-    if (!isa<TemplateTypeParmDecl>(Params->getParam(0)))
-      return false;
-
-    // It's the right template.
-    StdInitializerList = Template;
-  }
-
-  if (Template->getCanonicalDecl() != StdInitializerList->getCanonicalDecl())
-    return false;
-
-  // This is an instance of std::initializer_list. Find the argument type.
-  if (Element)
-    *Element = Arguments[0].getAsType();
-  return true;
-}
-
-static ClassTemplateDecl *LookupStdInitializerList(Sema &S, SourceLocation Loc){
-  NamespaceDecl *Std = S.getStdNamespace();
-  if (!Std) {
-    S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
-    return nullptr;
-  }
-
-  LookupResult Result(S, &S.PP.getIdentifierTable().get("initializer_list"),
-                      Loc, Sema::LookupOrdinaryName);
-  if (!S.LookupQualifiedName(Result, Std)) {
-    S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
-    return nullptr;
-  }
-  ClassTemplateDecl *Template = Result.getAsSingle<ClassTemplateDecl>();
-  if (!Template) {
-    Result.suppressDiagnostics();
-    // We found something weird. Complain about the first thing we found.
-    NamedDecl *Found = *Result.begin();
-    S.Diag(Found->getLocation(), diag::err_malformed_std_initializer_list);
-    return nullptr;
-  }
-
-  // We found some template called std::initializer_list. Now verify that it's
-  // correct.
-  TemplateParameterList *Params = Template->getTemplateParameters();
-  if (Params->getMinRequiredArguments() != 1 ||
-      !isa<TemplateTypeParmDecl>(Params->getParam(0))) {
-    S.Diag(Template->getLocation(), diag::err_malformed_std_initializer_list);
-    return nullptr;
-  }
-
-  return Template;
-}
-
-QualType Sema::BuildStdInitializerList(QualType Element, SourceLocation Loc) {
-  if (!StdInitializerList) {
-    StdInitializerList = LookupStdInitializerList(*this, Loc);
-    if (!StdInitializerList)
-      return QualType();
-  }
-
-  TemplateArgumentListInfo Args(Loc, Loc);
-  Args.addArgument(TemplateArgumentLoc(TemplateArgument(Element),
-                                       Context.getTrivialTypeSourceInfo(Element,
-                                                                        Loc)));
-  return Context.getCanonicalType(
-      CheckTemplateIdType(TemplateName(StdInitializerList), Loc, Args));
-}
-
-bool Sema::isInitListConstructor(const FunctionDecl *Ctor) {
-  // C++ [dcl.init.list]p2:
-  //   A constructor is an initializer-list constructor if its first parameter
-  //   is of type std::initializer_list<E> or reference to possibly cv-qualified
-  //   std::initializer_list<E> for some type E, and either there are no other
-  //   parameters or else all other parameters have default arguments.
-  if (Ctor->getNumParams() < 1 ||
-      (Ctor->getNumParams() > 1 && !Ctor->getParamDecl(1)->hasDefaultArg()))
-    return false;
-
-  QualType ArgType = Ctor->getParamDecl(0)->getType();
-  if (const ReferenceType *RT = ArgType->getAs<ReferenceType>())
-    ArgType = RT->getPointeeType().getUnqualifiedType();
-
-  return isStdInitializerList(ArgType, nullptr);
-}
-
-/// Determine whether a using statement is in a context where it will be
-/// apply in all contexts.
-static bool IsUsingDirectiveInToplevelContext(DeclContext *CurContext) {
-  switch (CurContext->getDeclKind()) {
-    case Decl::TranslationUnit:
-      return true;
-    case Decl::LinkageSpec:
-      return IsUsingDirectiveInToplevelContext(CurContext->getParent());
-    default:
-      return false;
-  }
-}
-
-namespace {
-
-// Callback to only accept typo corrections that are namespaces.
-class NamespaceValidatorCCC : public CorrectionCandidateCallback {
-public:
-  bool ValidateCandidate(const TypoCorrection &candidate) override {
-    if (NamedDecl *ND = candidate.getCorrectionDecl())
-      return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
-    return false;
-  }
-};
-
-}
-
-static bool TryNamespaceTypoCorrection(Sema &S, LookupResult &R, Scope *Sc,
-                                       CXXScopeSpec &SS,
-                                       SourceLocation IdentLoc,
-                                       IdentifierInfo *Ident) {
-  R.clear();
-  if (TypoCorrection Corrected =
-          S.CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), Sc, &SS,
-                        llvm::make_unique<NamespaceValidatorCCC>(),
-                        Sema::CTK_ErrorRecovery)) {
-    if (DeclContext *DC = S.computeDeclContext(SS, false)) {
-      std::string CorrectedStr(Corrected.getAsString(S.getLangOpts()));
-      bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
-                              Ident->getName().equals(CorrectedStr);
-      S.diagnoseTypo(Corrected,
-                     S.PDiag(diag::err_using_directive_member_suggest)
-                       << Ident << DC << DroppedSpecifier << SS.getRange(),
-                     S.PDiag(diag::note_namespace_defined_here));
-    } else {
-      S.diagnoseTypo(Corrected,
-                     S.PDiag(diag::err_using_directive_suggest) << Ident,
-                     S.PDiag(diag::note_namespace_defined_here));
-    }
-    R.addDecl(Corrected.getFoundDecl());
-    return true;
-  }
-  return false;
-}
-
-Decl *Sema::ActOnUsingDirective(Scope *S, SourceLocation UsingLoc,
-                                SourceLocation NamespcLoc, CXXScopeSpec &SS,
-                                SourceLocation IdentLoc,
-                                IdentifierInfo *NamespcName,
-                                const ParsedAttributesView &AttrList) {
-  assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
-  assert(NamespcName && "Invalid NamespcName.");
-  assert(IdentLoc.isValid() && "Invalid NamespceName location.");
-
-  // This can only happen along a recovery path.
-  while (S->isTemplateParamScope())
-    S = S->getParent();
-  assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
-
-  UsingDirectiveDecl *UDir = nullptr;
-  NestedNameSpecifier *Qualifier = nullptr;
-  if (SS.isSet())
-    Qualifier = SS.getScopeRep();
-
-  // Lookup namespace name.
-  LookupResult R(*this, NamespcName, IdentLoc, LookupNamespaceName);
-  LookupParsedName(R, S, &SS);
-  if (R.isAmbiguous())
-    return nullptr;
-
-  if (R.empty()) {
-    R.clear();
-    // Allow "using namespace std;" or "using namespace ::std;" even if
-    // "std" hasn't been defined yet, for GCC compatibility.
-    if ((!Qualifier || Qualifier->getKind() == NestedNameSpecifier::Global) &&
-        NamespcName->isStr("std")) {
-      Diag(IdentLoc, diag::ext_using_undefined_std);
-      R.addDecl(getOrCreateStdNamespace());
-      R.resolveKind();
-    }
-    // Otherwise, attempt typo correction.
-    else TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, NamespcName);
-  }
-
-  if (!R.empty()) {
-    NamedDecl *Named = R.getRepresentativeDecl();
-    NamespaceDecl *NS = R.getAsSingle<NamespaceDecl>();
-    assert(NS && "expected namespace decl");
-
-    // The use of a nested name specifier may trigger deprecation warnings.
-    DiagnoseUseOfDecl(Named, IdentLoc);
-
-    // C++ [namespace.udir]p1:
-    //   A using-directive specifies that the names in the nominated
-    //   namespace can be used in the scope in which the
-    //   using-directive appears after the using-directive. During
-    //   unqualified name lookup (3.4.1), the names appear as if they
-    //   were declared in the nearest enclosing namespace which
-    //   contains both the using-directive and the nominated
-    //   namespace. [Note: in this context, "contains" means "contains
-    //   directly or indirectly". ]
-
-    // Find enclosing context containing both using-directive and
-    // nominated namespace.
-    DeclContext *CommonAncestor = NS;
-    while (CommonAncestor && !CommonAncestor->Encloses(CurContext))
-      CommonAncestor = CommonAncestor->getParent();
-
-    UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, NamespcLoc,
-                                      SS.getWithLocInContext(Context),
-                                      IdentLoc, Named, CommonAncestor);
-
-    if (IsUsingDirectiveInToplevelContext(CurContext) &&
-        !SourceMgr.isInMainFile(SourceMgr.getExpansionLoc(IdentLoc))) {
-      Diag(IdentLoc, diag::warn_using_directive_in_header);
-    }
-
-    PushUsingDirective(S, UDir);
-  } else {
-    Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
-  }
-
-  if (UDir)
-    ProcessDeclAttributeList(S, UDir, AttrList);
-
-  return UDir;
-}
-
-void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) {
-  // If the scope has an associated entity and the using directive is at
-  // namespace or translation unit scope, add the UsingDirectiveDecl into
-  // its lookup structure so qualified name lookup can find it.
-  DeclContext *Ctx = S->getEntity();
-  if (Ctx && !Ctx->isFunctionOrMethod())
-    Ctx->addDecl(UDir);
-  else
-    // Otherwise, it is at block scope. The using-directives will affect lookup
-    // only to the end of the scope.
-    S->PushUsingDirective(UDir);
-}
-
-Decl *Sema::ActOnUsingDeclaration(Scope *S, AccessSpecifier AS,
-                                  SourceLocation UsingLoc,
-                                  SourceLocation TypenameLoc, CXXScopeSpec &SS,
-                                  UnqualifiedId &Name,
-                                  SourceLocation EllipsisLoc,
-                                  const ParsedAttributesView &AttrList) {
-  assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
-
-  if (SS.isEmpty()) {
-    Diag(Name.getBeginLoc(), diag::err_using_requires_qualname);
-    return nullptr;
-  }
-
-  switch (Name.getKind()) {
-  case UnqualifiedIdKind::IK_ImplicitSelfParam:
-  case UnqualifiedIdKind::IK_Identifier:
-  case UnqualifiedIdKind::IK_OperatorFunctionId:
-  case UnqualifiedIdKind::IK_LiteralOperatorId:
-  case UnqualifiedIdKind::IK_ConversionFunctionId:
-    break;
-
-  case UnqualifiedIdKind::IK_ConstructorName:
-  case UnqualifiedIdKind::IK_ConstructorTemplateId:
-    // C++11 inheriting constructors.
-    Diag(Name.getBeginLoc(),
-         getLangOpts().CPlusPlus11
-             ? diag::warn_cxx98_compat_using_decl_constructor
-             : diag::err_using_decl_constructor)
-        << SS.getRange();
-
-    if (getLangOpts().CPlusPlus11) break;
-
-    return nullptr;
-
-  case UnqualifiedIdKind::IK_DestructorName:
-    Diag(Name.getBeginLoc(), diag::err_using_decl_destructor) << SS.getRange();
-    return nullptr;
-
-  case UnqualifiedIdKind::IK_TemplateId:
-    Diag(Name.getBeginLoc(), diag::err_using_decl_template_id)
-        << SourceRange(Name.TemplateId->LAngleLoc, Name.TemplateId->RAngleLoc);
-    return nullptr;
-
-  case UnqualifiedIdKind::IK_DeductionGuideName:
-    llvm_unreachable("cannot parse qualified deduction guide name");
-  }
-
-  DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
-  DeclarationName TargetName = TargetNameInfo.getName();
-  if (!TargetName)
-    return nullptr;
-
-  // Warn about access declarations.
-  if (UsingLoc.isInvalid()) {
-    Diag(Name.getBeginLoc(), getLangOpts().CPlusPlus11
-                                 ? diag::err_access_decl
-                                 : diag::warn_access_decl_deprecated)
-        << FixItHint::CreateInsertion(SS.getRange().getBegin(), "using ");
-  }
-
-  if (EllipsisLoc.isInvalid()) {
-    if (DiagnoseUnexpandedParameterPack(SS, UPPC_UsingDeclaration) ||
-        DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC_UsingDeclaration))
-      return nullptr;
-  } else {
-    if (!SS.getScopeRep()->containsUnexpandedParameterPack() &&
-        !TargetNameInfo.containsUnexpandedParameterPack()) {
-      Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
-        << SourceRange(SS.getBeginLoc(), TargetNameInfo.getEndLoc());
-      EllipsisLoc = SourceLocation();
-    }
-  }
-
-  NamedDecl *UD =
-      BuildUsingDeclaration(S, AS, UsingLoc, TypenameLoc.isValid(), TypenameLoc,
-                            SS, TargetNameInfo, EllipsisLoc, AttrList,
-                            /*IsInstantiation*/false);
-  if (UD)
-    PushOnScopeChains(UD, S, /*AddToContext*/ false);
-
-  return UD;
-}
-
-/// Determine whether a using declaration considers the given
-/// declarations as "equivalent", e.g., if they are redeclarations of
-/// the same entity or are both typedefs of the same type.
-static bool
-IsEquivalentForUsingDecl(ASTContext &Context, NamedDecl *D1, NamedDecl *D2) {
-  if (D1->getCanonicalDecl() == D2->getCanonicalDecl())
-    return true;
-
-  if (TypedefNameDecl *TD1 = dyn_cast<TypedefNameDecl>(D1))
-    if (TypedefNameDecl *TD2 = dyn_cast<TypedefNameDecl>(D2))
-      return Context.hasSameType(TD1->getUnderlyingType(),
-                                 TD2->getUnderlyingType());
-
-  return false;
-}
-
-
-/// Determines whether to create a using shadow decl for a particular
-/// decl, given the set of decls existing prior to this using lookup.
-bool Sema::CheckUsingShadowDecl(UsingDecl *Using, NamedDecl *Orig,
-                                const LookupResult &Previous,
-                                UsingShadowDecl *&PrevShadow) {
-  // Diagnose finding a decl which is not from a base class of the
-  // current class.  We do this now because there are cases where this
-  // function will silently decide not to build a shadow decl, which
-  // will pre-empt further diagnostics.
-  //
-  // We don't need to do this in C++11 because we do the check once on
-  // the qualifier.
-  //
-  // FIXME: diagnose the following if we care enough:
-  //   struct A { int foo; };
-  //   struct B : A { using A::foo; };
-  //   template <class T> struct C : A {};
-  //   template <class T> struct D : C<T> { using B::foo; } // <---
-  // This is invalid (during instantiation) in C++03 because B::foo
-  // resolves to the using decl in B, which is not a base class of D<T>.
-  // We can't diagnose it immediately because C<T> is an unknown
-  // specialization.  The UsingShadowDecl in D<T> then points directly
-  // to A::foo, which will look well-formed when we instantiate.
-  // The right solution is to not collapse the shadow-decl chain.
-  if (!getLangOpts().CPlusPlus11 && CurContext->isRecord()) {
-    DeclContext *OrigDC = Orig->getDeclContext();
-
-    // Handle enums and anonymous structs.
-    if (isa<EnumDecl>(OrigDC)) OrigDC = OrigDC->getParent();
-    CXXRecordDecl *OrigRec = cast<CXXRecordDecl>(OrigDC);
-    while (OrigRec->isAnonymousStructOrUnion())
-      OrigRec = cast<CXXRecordDecl>(OrigRec->getDeclContext());
-
-    if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(OrigRec)) {
-      if (OrigDC == CurContext) {
-        Diag(Using->getLocation(),
-             diag::err_using_decl_nested_name_specifier_is_current_class)
-          << Using->getQualifierLoc().getSourceRange();
-        Diag(Orig->getLocation(), diag::note_using_decl_target);
-        Using->setInvalidDecl();
-        return true;
-      }
-
-      Diag(Using->getQualifierLoc().getBeginLoc(),
-           diag::err_using_decl_nested_name_specifier_is_not_base_class)
-        << Using->getQualifier()
-        << cast<CXXRecordDecl>(CurContext)
-        << Using->getQualifierLoc().getSourceRange();
-      Diag(Orig->getLocation(), diag::note_using_decl_target);
-      Using->setInvalidDecl();
-      return true;
-    }
-  }
-
-  if (Previous.empty()) return false;
-
-  NamedDecl *Target = Orig;
-  if (isa<UsingShadowDecl>(Target))
-    Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
-
-  // If the target happens to be one of the previous declarations, we
-  // don't have a conflict.
-  //
-  // FIXME: but we might be increasing its access, in which case we
-  // should redeclare it.
-  NamedDecl *NonTag = nullptr, *Tag = nullptr;
-  bool FoundEquivalentDecl = false;
-  for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
-         I != E; ++I) {
-    NamedDecl *D = (*I)->getUnderlyingDecl();
-    // We can have UsingDecls in our Previous results because we use the same
-    // LookupResult for checking whether the UsingDecl itself is a valid
-    // redeclaration.
-    if (isa<UsingDecl>(D) || isa<UsingPackDecl>(D))
-      continue;
-
-    if (auto *RD = dyn_cast<CXXRecordDecl>(D)) {
-      // C++ [class.mem]p19:
-      //   If T is the name of a class, then [every named member other than
-      //   a non-static data member] shall have a name different from T
-      if (RD->isInjectedClassName() && !isa<FieldDecl>(Target) &&
-          !isa<IndirectFieldDecl>(Target) &&
-          !isa<UnresolvedUsingValueDecl>(Target) &&
-          DiagnoseClassNameShadow(
-              CurContext,
-              DeclarationNameInfo(Using->getDeclName(), Using->getLocation())))
-        return true;
-    }
-
-    if (IsEquivalentForUsingDecl(Context, D, Target)) {
-      if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(*I))
-        PrevShadow = Shadow;
-      FoundEquivalentDecl = true;
-    } else if (isEquivalentInternalLinkageDeclaration(D, Target)) {
-      // We don't conflict with an existing using shadow decl of an equivalent
-      // declaration, but we're not a redeclaration of it.
-      FoundEquivalentDecl = true;
-    }
-
-    if (isVisible(D))
-      (isa<TagDecl>(D) ? Tag : NonTag) = D;
-  }
-
-  if (FoundEquivalentDecl)
-    return false;
-
-  if (FunctionDecl *FD = Target->getAsFunction()) {
-    NamedDecl *OldDecl = nullptr;
-    switch (CheckOverload(nullptr, FD, Previous, OldDecl,
-                          /*IsForUsingDecl*/ true)) {
-    case Ovl_Overload:
-      return false;
-
-    case Ovl_NonFunction:
-      Diag(Using->getLocation(), diag::err_using_decl_conflict);
-      break;
-
-    // We found a decl with the exact signature.
-    case Ovl_Match:
-      // If we're in a record, we want to hide the target, so we
-      // return true (without a diagnostic) to tell the caller not to
-      // build a shadow decl.
-      if (CurContext->isRecord())
-        return true;
-
-      // If we're not in a record, this is an error.
-      Diag(Using->getLocation(), diag::err_using_decl_conflict);
-      break;
-    }
-
-    Diag(Target->getLocation(), diag::note_using_decl_target);
-    Diag(OldDecl->getLocation(), diag::note_using_decl_conflict);
-    Using->setInvalidDecl();
-    return true;
-  }
-
-  // Target is not a function.
-
-  if (isa<TagDecl>(Target)) {
-    // No conflict between a tag and a non-tag.
-    if (!Tag) return false;
-
-    Diag(Using->getLocation(), diag::err_using_decl_conflict);
-    Diag(Target->getLocation(), diag::note_using_decl_target);
-    Diag(Tag->getLocation(), diag::note_using_decl_conflict);
-    Using->setInvalidDecl();
-    return true;
-  }
-
-  // No conflict between a tag and a non-tag.
-  if (!NonTag) return false;
-
-  Diag(Using->getLocation(), diag::err_using_decl_conflict);
-  Diag(Target->getLocation(), diag::note_using_decl_target);
-  Diag(NonTag->getLocation(), diag::note_using_decl_conflict);
-  Using->setInvalidDecl();
-  return true;
-}
-
-/// Determine whether a direct base class is a virtual base class.
-static bool isVirtualDirectBase(CXXRecordDecl *Derived, CXXRecordDecl *Base) {
-  if (!Derived->getNumVBases())
-    return false;
-  for (auto &B : Derived->bases())
-    if (B.getType()->getAsCXXRecordDecl() == Base)
-      return B.isVirtual();
-  llvm_unreachable("not a direct base class");
-}
-
-/// Builds a shadow declaration corresponding to a 'using' declaration.
-UsingShadowDecl *Sema::BuildUsingShadowDecl(Scope *S,
-                                            UsingDecl *UD,
-                                            NamedDecl *Orig,
-                                            UsingShadowDecl *PrevDecl) {
-  // If we resolved to another shadow declaration, just coalesce them.
-  NamedDecl *Target = Orig;
-  if (isa<UsingShadowDecl>(Target)) {
-    Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
-    assert(!isa<UsingShadowDecl>(Target) && "nested shadow declaration");
-  }
-
-  NamedDecl *NonTemplateTarget = Target;
-  if (auto *TargetTD = dyn_cast<TemplateDecl>(Target))
-    NonTemplateTarget = TargetTD->getTemplatedDecl();
-
-  UsingShadowDecl *Shadow;
-  if (isa<CXXConstructorDecl>(NonTemplateTarget)) {
-    bool IsVirtualBase =
-        isVirtualDirectBase(cast<CXXRecordDecl>(CurContext),
-                            UD->getQualifier()->getAsRecordDecl());
-    Shadow = ConstructorUsingShadowDecl::Create(
-        Context, CurContext, UD->getLocation(), UD, Orig, IsVirtualBase);
-  } else {
-    Shadow = UsingShadowDecl::Create(Context, CurContext, UD->getLocation(), UD,
-                                     Target);
-  }
-  UD->addShadowDecl(Shadow);
-
-  Shadow->setAccess(UD->getAccess());
-  if (Orig->isInvalidDecl() || UD->isInvalidDecl())
-    Shadow->setInvalidDecl();
-
-  Shadow->setPreviousDecl(PrevDecl);
-
-  if (S)
-    PushOnScopeChains(Shadow, S);
-  else
-    CurContext->addDecl(Shadow);
-
-
-  return Shadow;
-}
-
-/// Hides a using shadow declaration.  This is required by the current
-/// using-decl implementation when a resolvable using declaration in a
-/// class is followed by a declaration which would hide or override
-/// one or more of the using decl's targets; for example:
-///
-///   struct Base { void foo(int); };
-///   struct Derived : Base {
-///     using Base::foo;
-///     void foo(int);
-///   };
-///
-/// The governing language is C++03 [namespace.udecl]p12:
-///
-///   When a using-declaration brings names from a base class into a
-///   derived class scope, member functions in the derived class
-///   override and/or hide member functions with the same name and
-///   parameter types in a base class (rather than conflicting).
-///
-/// There are two ways to implement this:
-///   (1) optimistically create shadow decls when they're not hidden
-///       by existing declarations, or
-///   (2) don't create any shadow decls (or at least don't make them
-///       visible) until we've fully parsed/instantiated the class.
-/// The problem with (1) is that we might have to retroactively remove
-/// a shadow decl, which requires several O(n) operations because the
-/// decl structures are (very reasonably) not designed for removal.
-/// (2) avoids this but is very fiddly and phase-dependent.
-void Sema::HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow) {
-  if (Shadow->getDeclName().getNameKind() ==
-        DeclarationName::CXXConversionFunctionName)
-    cast<CXXRecordDecl>(Shadow->getDeclContext())->removeConversion(Shadow);
-
-  // Remove it from the DeclContext...
-  Shadow->getDeclContext()->removeDecl(Shadow);
-
-  // ...and the scope, if applicable...
-  if (S) {
-    S->RemoveDecl(Shadow);
-    IdResolver.RemoveDecl(Shadow);
-  }
-
-  // ...and the using decl.
-  Shadow->getUsingDecl()->removeShadowDecl(Shadow);
-
-  // TODO: complain somehow if Shadow was used.  It shouldn't
-  // be possible for this to happen, because...?
-}
-
-/// Find the base specifier for a base class with the given type.
-static CXXBaseSpecifier *findDirectBaseWithType(CXXRecordDecl *Derived,
-                                                QualType DesiredBase,
-                                                bool &AnyDependentBases) {
-  // Check whether the named type is a direct base class.
-  CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified();
-  for (auto &Base : Derived->bases()) {
-    CanQualType BaseType = Base.getType()->getCanonicalTypeUnqualified();
-    if (CanonicalDesiredBase == BaseType)
-      return &Base;
-    if (BaseType->isDependentType())
-      AnyDependentBases = true;
-  }
-  return nullptr;
-}
-
-namespace {
-class UsingValidatorCCC : public CorrectionCandidateCallback {
-public:
-  UsingValidatorCCC(bool HasTypenameKeyword, bool IsInstantiation,
-                    NestedNameSpecifier *NNS, CXXRecordDecl *RequireMemberOf)
-      : HasTypenameKeyword(HasTypenameKeyword),
-        IsInstantiation(IsInstantiation), OldNNS(NNS),
-        RequireMemberOf(RequireMemberOf) {}
-
-  bool ValidateCandidate(const TypoCorrection &Candidate) override {
-    NamedDecl *ND = Candidate.getCorrectionDecl();
-
-    // Keywords are not valid here.
-    if (!ND || isa<NamespaceDecl>(ND))
-      return false;
-
-    // Completely unqualified names are invalid for a 'using' declaration.
-    if (Candidate.WillReplaceSpecifier() && !Candidate.getCorrectionSpecifier())
-      return false;
-
-    // FIXME: Don't correct to a name that CheckUsingDeclRedeclaration would
-    // reject.
-
-    if (RequireMemberOf) {
-      auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
-      if (FoundRecord && FoundRecord->isInjectedClassName()) {
-        // No-one ever wants a using-declaration to name an injected-class-name
-        // of a base class, unless they're declaring an inheriting constructor.
-        ASTContext &Ctx = ND->getASTContext();
-        if (!Ctx.getLangOpts().CPlusPlus11)
-          return false;
-        QualType FoundType = Ctx.getRecordType(FoundRecord);
-
-        // Check that the injected-class-name is named as a member of its own
-        // type; we don't want to suggest 'using Derived::Base;', since that
-        // means something else.
-        NestedNameSpecifier *Specifier =
-            Candidate.WillReplaceSpecifier()
-                ? Candidate.getCorrectionSpecifier()
-                : OldNNS;
-        if (!Specifier->getAsType() ||
-            !Ctx.hasSameType(QualType(Specifier->getAsType(), 0), FoundType))
-          return false;
-
-        // Check that this inheriting constructor declaration actually names a
-        // direct base class of the current class.
-        bool AnyDependentBases = false;
-        if (!findDirectBaseWithType(RequireMemberOf,
-                                    Ctx.getRecordType(FoundRecord),
-                                    AnyDependentBases) &&
-            !AnyDependentBases)
-          return false;
-      } else {
-        auto *RD = dyn_cast<CXXRecordDecl>(ND->getDeclContext());
-        if (!RD || RequireMemberOf->isProvablyNotDerivedFrom(RD))
-          return false;
-
-        // FIXME: Check that the base class member is accessible?
-      }
-    } else {
-      auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
-      if (FoundRecord && FoundRecord->isInjectedClassName())
-        return false;
-    }
-
-    if (isa<TypeDecl>(ND))
-      return HasTypenameKeyword || !IsInstantiation;
-
-    return !HasTypenameKeyword;
-  }
-
-private:
-  bool HasTypenameKeyword;
-  bool IsInstantiation;
-  NestedNameSpecifier *OldNNS;
-  CXXRecordDecl *RequireMemberOf;
-};
-} // end anonymous namespace
-
-/// Builds a using declaration.
-///
-/// \param IsInstantiation - Whether this call arises from an
-///   instantiation of an unresolved using declaration.  We treat
-///   the lookup differently for these declarations.
-NamedDecl *Sema::BuildUsingDeclaration(
-    Scope *S, AccessSpecifier AS, SourceLocation UsingLoc,
-    bool HasTypenameKeyword, SourceLocation TypenameLoc, CXXScopeSpec &SS,
-    DeclarationNameInfo NameInfo, SourceLocation EllipsisLoc,
-    const ParsedAttributesView &AttrList, bool IsInstantiation) {
-  assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
-  SourceLocation IdentLoc = NameInfo.getLoc();
-  assert(IdentLoc.isValid() && "Invalid TargetName location.");
-
-  // FIXME: We ignore attributes for now.
-
-  // For an inheriting constructor declaration, the name of the using
-  // declaration is the name of a constructor in this class, not in the
-  // base class.
-  DeclarationNameInfo UsingName = NameInfo;
-  if (UsingName.getName().getNameKind() == DeclarationName::CXXConstructorName)
-    if (auto *RD = dyn_cast<CXXRecordDecl>(CurContext))
-      UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
-          Context.getCanonicalType(Context.getRecordType(RD))));
-
-  // Do the redeclaration lookup in the current scope.
-  LookupResult Previous(*this, UsingName, LookupUsingDeclName,
-                        ForVisibleRedeclaration);
-  Previous.setHideTags(false);
-  if (S) {
-    LookupName(Previous, S);
-
-    // It is really dumb that we have to do this.
-    LookupResult::Filter F = Previous.makeFilter();
-    while (F.hasNext()) {
-      NamedDecl *D = F.next();
-      if (!isDeclInScope(D, CurContext, S))
-        F.erase();
-      // If we found a local extern declaration that's not ordinarily visible,
-      // and this declaration is being added to a non-block scope, ignore it.
-      // We're only checking for scope conflicts here, not also for violations
-      // of the linkage rules.
-      else if (!CurContext->isFunctionOrMethod() && D->isLocalExternDecl() &&
-               !(D->getIdentifierNamespace() & Decl::IDNS_Ordinary))
-        F.erase();
-    }
-    F.done();
-  } else {
-    assert(IsInstantiation && "no scope in non-instantiation");
-    if (CurContext->isRecord())
-      LookupQualifiedName(Previous, CurContext);
-    else {
-      // No redeclaration check is needed here; in non-member contexts we
-      // diagnosed all possible conflicts with other using-declarations when
-      // building the template:
-      //
-      // For a dependent non-type using declaration, the only valid case is
-      // if we instantiate to a single enumerator. We check for conflicts
-      // between shadow declarations we introduce, and we check in the template
-      // definition for conflicts between a non-type using declaration and any
-      // other declaration, which together covers all cases.
-      //
-      // A dependent typename using declaration will never successfully
-      // instantiate, since it will always name a class member, so we reject
-      // that in the template definition.
-    }
-  }
-
-  // Check for invalid redeclarations.
-  if (CheckUsingDeclRedeclaration(UsingLoc, HasTypenameKeyword,
-                                  SS, IdentLoc, Previous))
-    return nullptr;
-
-  // Check for bad qualifiers.
-  if (CheckUsingDeclQualifier(UsingLoc, HasTypenameKeyword, SS, NameInfo,
-                              IdentLoc))
-    return nullptr;
-
-  DeclContext *LookupContext = computeDeclContext(SS);
-  NamedDecl *D;
-  NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
-  if (!LookupContext || EllipsisLoc.isValid()) {
-    if (HasTypenameKeyword) {
-      // FIXME: not all declaration name kinds are legal here
-      D = UnresolvedUsingTypenameDecl::Create(Context, CurContext,
-                                              UsingLoc, TypenameLoc,
-                                              QualifierLoc,
-                                              IdentLoc, NameInfo.getName(),
-                                              EllipsisLoc);
-    } else {
-      D = UnresolvedUsingValueDecl::Create(Context, CurContext, UsingLoc,
-                                           QualifierLoc, NameInfo, EllipsisLoc);
-    }
-    D->setAccess(AS);
-    CurContext->addDecl(D);
-    return D;
-  }
-
-  auto Build = [&](bool Invalid) {
-    UsingDecl *UD =
-        UsingDecl::Create(Context, CurContext, UsingLoc, QualifierLoc,
-                          UsingName, HasTypenameKeyword);
-    UD->setAccess(AS);
-    CurContext->addDecl(UD);
-    UD->setInvalidDecl(Invalid);
-    return UD;
-  };
-  auto BuildInvalid = [&]{ return Build(true); };
-  auto BuildValid = [&]{ return Build(false); };
-
-  if (RequireCompleteDeclContext(SS, LookupContext))
-    return BuildInvalid();
-
-  // Look up the target name.
-  LookupResult R(*this, NameInfo, LookupOrdinaryName);
-
-  // Unlike most lookups, we don't always want to hide tag
-  // declarations: tag names are visible through the using declaration
-  // even if hidden by ordinary names, *except* in a dependent context
-  // where it's important for the sanity of two-phase lookup.
-  if (!IsInstantiation)
-    R.setHideTags(false);
-
-  // For the purposes of this lookup, we have a base object type
-  // equal to that of the current context.
-  if (CurContext->isRecord()) {
-    R.setBaseObjectType(
-                   Context.getTypeDeclType(cast<CXXRecordDecl>(CurContext)));
-  }
-
-  LookupQualifiedName(R, LookupContext);
-
-  // Try to correct typos if possible. If constructor name lookup finds no
-  // results, that means the named class has no explicit constructors, and we
-  // suppressed declaring implicit ones (probably because it's dependent or
-  // invalid).
-  if (R.empty() &&
-      NameInfo.getName().getNameKind() != DeclarationName::CXXConstructorName) {
-    // HACK: Work around a bug in libstdc++'s detection of ::gets. Sometimes
-    // it will believe that glibc provides a ::gets in cases where it does not,
-    // and will try to pull it into namespace std with a using-declaration.
-    // Just ignore the using-declaration in that case.
-    auto *II = NameInfo.getName().getAsIdentifierInfo();
-    if (getLangOpts().CPlusPlus14 && II && II->isStr("gets") &&
-        CurContext->isStdNamespace() &&
-        isa<TranslationUnitDecl>(LookupContext) &&
-        getSourceManager().isInSystemHeader(UsingLoc))
-      return nullptr;
-    if (TypoCorrection Corrected = CorrectTypo(
-            R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
-            llvm::make_unique<UsingValidatorCCC>(
-                HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),
-                dyn_cast<CXXRecordDecl>(CurContext)),
-            CTK_ErrorRecovery)) {
-      // We reject candidates where DroppedSpecifier == true, hence the
-      // literal '0' below.
-      diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
-                                << NameInfo.getName() << LookupContext << 0
-                                << SS.getRange());
-
-      // If we picked a correction with no attached Decl we can't do anything
-      // useful with it, bail out.
-      NamedDecl *ND = Corrected.getCorrectionDecl();
-      if (!ND)
-        return BuildInvalid();
-
-      // If we corrected to an inheriting constructor, handle it as one.
-      auto *RD = dyn_cast<CXXRecordDecl>(ND);
-      if (RD && RD->isInjectedClassName()) {
-        // The parent of the injected class name is the class itself.
-        RD = cast<CXXRecordDecl>(RD->getParent());
-
-        // Fix up the information we'll use to build the using declaration.
-        if (Corrected.WillReplaceSpecifier()) {
-          NestedNameSpecifierLocBuilder Builder;
-          Builder.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
-                              QualifierLoc.getSourceRange());
-          QualifierLoc = Builder.getWithLocInContext(Context);
-        }
-
-        // In this case, the name we introduce is the name of a derived class
-        // constructor.
-        auto *CurClass = cast<CXXRecordDecl>(CurContext);
-        UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
-            Context.getCanonicalType(Context.getRecordType(CurClass))));
-        UsingName.setNamedTypeInfo(nullptr);
-        for (auto *Ctor : LookupConstructors(RD))
-          R.addDecl(Ctor);
-        R.resolveKind();
-      } else {
-        // FIXME: Pick up all the declarations if we found an overloaded
-        // function.
-        UsingName.setName(ND->getDeclName());
-        R.addDecl(ND);
-      }
-    } else {
-      Diag(IdentLoc, diag::err_no_member)
-        << NameInfo.getName() << LookupContext << SS.getRange();
-      return BuildInvalid();
-    }
-  }
-
-  if (R.isAmbiguous())
-    return BuildInvalid();
-
-  if (HasTypenameKeyword) {
-    // If we asked for a typename and got a non-type decl, error out.
-    if (!R.getAsSingle<TypeDecl>()) {
-      Diag(IdentLoc, diag::err_using_typename_non_type);
-      for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
-        Diag((*I)->getUnderlyingDecl()->getLocation(),
-             diag::note_using_decl_target);
-      return BuildInvalid();
-    }
-  } else {
-    // If we asked for a non-typename and we got a type, error out,
-    // but only if this is an instantiation of an unresolved using
-    // decl.  Otherwise just silently find the type name.
-    if (IsInstantiation && R.getAsSingle<TypeDecl>()) {
-      Diag(IdentLoc, diag::err_using_dependent_value_is_type);
-      Diag(R.getFoundDecl()->getLocation(), diag::note_using_decl_target);
-      return BuildInvalid();
-    }
-  }
-
-  // C++14 [namespace.udecl]p6:
-  // A using-declaration shall not name a namespace.
-  if (R.getAsSingle<NamespaceDecl>()) {
-    Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_namespace)
-      << SS.getRange();
-    return BuildInvalid();
-  }
-
-  // C++14 [namespace.udecl]p7:
-  // A using-declaration shall not name a scoped enumerator.
-  if (auto *ED = R.getAsSingle<EnumConstantDecl>()) {
-    if (cast<EnumDecl>(ED->getDeclContext())->isScoped()) {
-      Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_scoped_enum)
-        << SS.getRange();
-      return BuildInvalid();
-    }
-  }
-
-  UsingDecl *UD = BuildValid();
-
-  // Some additional rules apply to inheriting constructors.
-  if (UsingName.getName().getNameKind() ==
-        DeclarationName::CXXConstructorName) {
-    // Suppress access diagnostics; the access check is instead performed at the
-    // point of use for an inheriting constructor.
-    R.suppressDiagnostics();
-    if (CheckInheritingConstructorUsingDecl(UD))
-      return UD;
-  }
-
-  for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
-    UsingShadowDecl *PrevDecl = nullptr;
-    if (!CheckUsingShadowDecl(UD, *I, Previous, PrevDecl))
-      BuildUsingShadowDecl(S, UD, *I, PrevDecl);
-  }
-
-  return UD;
-}
-
-NamedDecl *Sema::BuildUsingPackDecl(NamedDecl *InstantiatedFrom,
-                                    ArrayRef<NamedDecl *> Expansions) {
-  assert(isa<UnresolvedUsingValueDecl>(InstantiatedFrom) ||
-         isa<UnresolvedUsingTypenameDecl>(InstantiatedFrom) ||
-         isa<UsingPackDecl>(InstantiatedFrom));
-
-  auto *UPD =
-      UsingPackDecl::Create(Context, CurContext, InstantiatedFrom, Expansions);
-  UPD->setAccess(InstantiatedFrom->getAccess());
-  CurContext->addDecl(UPD);
-  return UPD;
-}
-
-/// Additional checks for a using declaration referring to a constructor name.
-bool Sema::CheckInheritingConstructorUsingDecl(UsingDecl *UD) {
-  assert(!UD->hasTypename() && "expecting a constructor name");
-
-  const Type *SourceType = UD->getQualifier()->getAsType();
-  assert(SourceType &&
-         "Using decl naming constructor doesn't have type in scope spec.");
-  CXXRecordDecl *TargetClass = cast<CXXRecordDecl>(CurContext);
-
-  // Check whether the named type is a direct base class.
-  bool AnyDependentBases = false;
-  auto *Base = findDirectBaseWithType(TargetClass, QualType(SourceType, 0),
-                                      AnyDependentBases);
-  if (!Base && !AnyDependentBases) {
-    Diag(UD->getUsingLoc(),
-         diag::err_using_decl_constructor_not_in_direct_base)
-      << UD->getNameInfo().getSourceRange()
-      << QualType(SourceType, 0) << TargetClass;
-    UD->setInvalidDecl();
-    return true;
-  }
-
-  if (Base)
-    Base->setInheritConstructors();
-
-  return false;
-}
-
-/// Checks that the given using declaration is not an invalid
-/// redeclaration.  Note that this is checking only for the using decl
-/// itself, not for any ill-formedness among the UsingShadowDecls.
-bool Sema::CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
-                                       bool HasTypenameKeyword,
-                                       const CXXScopeSpec &SS,
-                                       SourceLocation NameLoc,
-                                       const LookupResult &Prev) {
-  NestedNameSpecifier *Qual = SS.getScopeRep();
-
-  // C++03 [namespace.udecl]p8:
-  // C++0x [namespace.udecl]p10:
-  //   A using-declaration is a declaration and can therefore be used
-  //   repeatedly where (and only where) multiple declarations are
-  //   allowed.
-  //
-  // That's in non-member contexts.
-  if (!CurContext->getRedeclContext()->isRecord()) {
-    // A dependent qualifier outside a class can only ever resolve to an
-    // enumeration type. Therefore it conflicts with any other non-type
-    // declaration in the same scope.
-    // FIXME: How should we check for dependent type-type conflicts at block
-    // scope?
-    if (Qual->isDependent() && !HasTypenameKeyword) {
-      for (auto *D : Prev) {
-        if (!isa<TypeDecl>(D) && !isa<UsingDecl>(D) && !isa<UsingPackDecl>(D)) {
-          bool OldCouldBeEnumerator =
-              isa<UnresolvedUsingValueDecl>(D) || isa<EnumConstantDecl>(D);
-          Diag(NameLoc,
-               OldCouldBeEnumerator ? diag::err_redefinition
-                                    : diag::err_redefinition_different_kind)
-              << Prev.getLookupName();
-          Diag(D->getLocation(), diag::note_previous_definition);
-          return true;
-        }
-      }
-    }
-    return false;
-  }
-
-  for (LookupResult::iterator I = Prev.begin(), E = Prev.end(); I != E; ++I) {
-    NamedDecl *D = *I;
-
-    bool DTypename;
-    NestedNameSpecifier *DQual;
-    if (UsingDecl *UD = dyn_cast<UsingDecl>(D)) {
-      DTypename = UD->hasTypename();
-      DQual = UD->getQualifier();
-    } else if (UnresolvedUsingValueDecl *UD
-                 = dyn_cast<UnresolvedUsingValueDecl>(D)) {
-      DTypename = false;
-      DQual = UD->getQualifier();
-    } else if (UnresolvedUsingTypenameDecl *UD
-                 = dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
-      DTypename = true;
-      DQual = UD->getQualifier();
-    } else continue;
-
-    // using decls differ if one says 'typename' and the other doesn't.
-    // FIXME: non-dependent using decls?
-    if (HasTypenameKeyword != DTypename) continue;
-
-    // using decls differ if they name different scopes (but note that
-    // template instantiation can cause this check to trigger when it
-    // didn't before instantiation).
-    if (Context.getCanonicalNestedNameSpecifier(Qual) !=
-        Context.getCanonicalNestedNameSpecifier(DQual))
-      continue;
-
-    Diag(NameLoc, diag::err_using_decl_redeclaration) << SS.getRange();
-    Diag(D->getLocation(), diag::note_using_decl) << 1;
-    return true;
-  }
-
-  return false;
-}
-
-
-/// Checks that the given nested-name qualifier used in a using decl
-/// in the current context is appropriately related to the current
-/// scope.  If an error is found, diagnoses it and returns true.
-bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc,
-                                   bool HasTypename,
-                                   const CXXScopeSpec &SS,
-                                   const DeclarationNameInfo &NameInfo,
-                                   SourceLocation NameLoc) {
-  DeclContext *NamedContext = computeDeclContext(SS);
-
-  if (!CurContext->isRecord()) {
-    // C++03 [namespace.udecl]p3:
-    // C++0x [namespace.udecl]p8:
-    //   A using-declaration for a class member shall be a member-declaration.
-
-    // If we weren't able to compute a valid scope, it might validly be a
-    // dependent class scope or a dependent enumeration unscoped scope. If
-    // we have a 'typename' keyword, the scope must resolve to a class type.
-    if ((HasTypename && !NamedContext) ||
-        (NamedContext && NamedContext->getRedeclContext()->isRecord())) {
-      auto *RD = NamedContext
-                     ? cast<CXXRecordDecl>(NamedContext->getRedeclContext())
-                     : nullptr;
-      if (RD && RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), RD))
-        RD = nullptr;
-
-      Diag(NameLoc, diag::err_using_decl_can_not_refer_to_class_member)
-        << SS.getRange();
-
-      // If we have a complete, non-dependent source type, try to suggest a
-      // way to get the same effect.
-      if (!RD)
-        return true;
-
-      // Find what this using-declaration was referring to.
-      LookupResult R(*this, NameInfo, LookupOrdinaryName);
-      R.setHideTags(false);
-      R.suppressDiagnostics();
-      LookupQualifiedName(R, RD);
-
-      if (R.getAsSingle<TypeDecl>()) {
-        if (getLangOpts().CPlusPlus11) {
-          // Convert 'using X::Y;' to 'using Y = X::Y;'.
-          Diag(SS.getBeginLoc(), diag::note_using_decl_class_member_workaround)
-            << 0 // alias declaration
-            << FixItHint::CreateInsertion(SS.getBeginLoc(),
-                                          NameInfo.getName().getAsString() +
-                                              " = ");
-        } else {
-          // Convert 'using X::Y;' to 'typedef X::Y Y;'.
-          SourceLocation InsertLoc = getLocForEndOfToken(NameInfo.getEndLoc());
-          Diag(InsertLoc, diag::note_using_decl_class_member_workaround)
-            << 1 // typedef declaration
-            << FixItHint::CreateReplacement(UsingLoc, "typedef")
-            << FixItHint::CreateInsertion(
-                   InsertLoc, " " + NameInfo.getName().getAsString());
-        }
-      } else if (R.getAsSingle<VarDecl>()) {
-        // Don't provide a fixit outside C++11 mode; we don't want to suggest
-        // repeating the type of the static data member here.
-        FixItHint FixIt;
-        if (getLangOpts().CPlusPlus11) {
-          // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
-          FixIt = FixItHint::CreateReplacement(
-              UsingLoc, "auto &" + NameInfo.getName().getAsString() + " = ");
-        }
-
-        Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
-          << 2 // reference declaration
-          << FixIt;
-      } else if (R.getAsSingle<EnumConstantDecl>()) {
-        // Don't provide a fixit outside C++11 mode; we don't want to suggest
-        // repeating the type of the enumeration here, and we can't do so if
-        // the type is anonymous.
-        FixItHint FixIt;
-        if (getLangOpts().CPlusPlus11) {
-          // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
-          FixIt = FixItHint::CreateReplacement(
-              UsingLoc,
-              "constexpr auto " + NameInfo.getName().getAsString() + " = ");
-        }
-
-        Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
-          << (getLangOpts().CPlusPlus11 ? 4 : 3) // const[expr] variable
-          << FixIt;
-      }
-      return true;
-    }
-
-    // Otherwise, this might be valid.
-    return false;
-  }
-
-  // The current scope is a record.
-
-  // If the named context is dependent, we can't decide much.
-  if (!NamedContext) {
-    // FIXME: in C++0x, we can diagnose if we can prove that the
-    // nested-name-specifier does not refer to a base class, which is
-    // still possible in some cases.
-
-    // Otherwise we have to conservatively report that things might be
-    // okay.
-    return false;
-  }
-
-  if (!NamedContext->isRecord()) {
-    // Ideally this would point at the last name in the specifier,
-    // but we don't have that level of source info.
-    Diag(SS.getRange().getBegin(),
-         diag::err_using_decl_nested_name_specifier_is_not_class)
-      << SS.getScopeRep() << SS.getRange();
-    return true;
-  }
-
-  if (!NamedContext->isDependentContext() &&
-      RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), NamedContext))
-    return true;
-
-  if (getLangOpts().CPlusPlus11) {
-    // C++11 [namespace.udecl]p3:
-    //   In a using-declaration used as a member-declaration, the
-    //   nested-name-specifier shall name a base class of the class
-    //   being defined.
-
-    if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(
-                                 cast<CXXRecordDecl>(NamedContext))) {
-      if (CurContext == NamedContext) {
-        Diag(NameLoc,
-             diag::err_using_decl_nested_name_specifier_is_current_class)
-          << SS.getRange();
-        return true;
-      }
-
-      if (!cast<CXXRecordDecl>(NamedContext)->isInvalidDecl()) {
-        Diag(SS.getRange().getBegin(),
-             diag::err_using_decl_nested_name_specifier_is_not_base_class)
-          << SS.getScopeRep()
-          << cast<CXXRecordDecl>(CurContext)
-          << SS.getRange();
-      }
-      return true;
-    }
-
-    return false;
-  }
-
-  // C++03 [namespace.udecl]p4:
-  //   A using-declaration used as a member-declaration shall refer
-  //   to a member of a base class of the class being defined [etc.].
-
-  // Salient point: SS doesn't have to name a base class as long as
-  // lookup only finds members from base classes.  Therefore we can
-  // diagnose here only if we can prove that that can't happen,
-  // i.e. if the class hierarchies provably don't intersect.
-
-  // TODO: it would be nice if "definitely valid" results were cached
-  // in the UsingDecl and UsingShadowDecl so that these checks didn't
-  // need to be repeated.
-
-  llvm::SmallPtrSet<const CXXRecordDecl *, 4> Bases;
-  auto Collect = [&Bases](const CXXRecordDecl *Base) {
-    Bases.insert(Base);
-    return true;
-  };
-
-  // Collect all bases. Return false if we find a dependent base.
-  if (!cast<CXXRecordDecl>(CurContext)->forallBases(Collect))
-    return false;
-
-  // Returns true if the base is dependent or is one of the accumulated base
-  // classes.
-  auto IsNotBase = [&Bases](const CXXRecordDecl *Base) {
-    return !Bases.count(Base);
-  };
-
-  // Return false if the class has a dependent base or if it or one
-  // of its bases is present in the base set of the current context.
-  if (Bases.count(cast<CXXRecordDecl>(NamedContext)) ||
-      !cast<CXXRecordDecl>(NamedContext)->forallBases(IsNotBase))
-    return false;
-
-  Diag(SS.getRange().getBegin(),
-       diag::err_using_decl_nested_name_specifier_is_not_base_class)
-    << SS.getScopeRep()
-    << cast<CXXRecordDecl>(CurContext)
-    << SS.getRange();
-
-  return true;
-}
-
-Decl *Sema::ActOnAliasDeclaration(Scope *S, AccessSpecifier AS,
-                                  MultiTemplateParamsArg TemplateParamLists,
-                                  SourceLocation UsingLoc, UnqualifiedId &Name,
-                                  const ParsedAttributesView &AttrList,
-                                  TypeResult Type, Decl *DeclFromDeclSpec) {
-  // Skip up to the relevant declaration scope.
-  while (S->isTemplateParamScope())
-    S = S->getParent();
-  assert((S->getFlags() & Scope::DeclScope) &&
-         "got alias-declaration outside of declaration scope");
-
-  if (Type.isInvalid())
-    return nullptr;
-
-  bool Invalid = false;
-  DeclarationNameInfo NameInfo = GetNameFromUnqualifiedId(Name);
-  TypeSourceInfo *TInfo = nullptr;
-  GetTypeFromParser(Type.get(), &TInfo);
-
-  if (DiagnoseClassNameShadow(CurContext, NameInfo))
-    return nullptr;
-
-  if (DiagnoseUnexpandedParameterPack(Name.StartLocation, TInfo,
-                                      UPPC_DeclarationType)) {
-    Invalid = true;
-    TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
-                                             TInfo->getTypeLoc().getBeginLoc());
-  }
-
-  LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
-                        TemplateParamLists.size()
-                            ? forRedeclarationInCurContext()
-                            : ForVisibleRedeclaration);
-  LookupName(Previous, S);
-
-  // Warn about shadowing the name of a template parameter.
-  if (Previous.isSingleResult() &&
-      Previous.getFoundDecl()->isTemplateParameter()) {
-    DiagnoseTemplateParameterShadow(Name.StartLocation,Previous.getFoundDecl());
-    Previous.clear();
-  }
-
-  assert(Name.Kind == UnqualifiedIdKind::IK_Identifier &&
-         "name in alias declaration must be an identifier");
-  TypeAliasDecl *NewTD = TypeAliasDecl::Create(Context, CurContext, UsingLoc,
-                                               Name.StartLocation,
-                                               Name.Identifier, TInfo);
-
-  NewTD->setAccess(AS);
-
-  if (Invalid)
-    NewTD->setInvalidDecl();
-
-  ProcessDeclAttributeList(S, NewTD, AttrList);
-  AddPragmaAttributes(S, NewTD);
-
-  CheckTypedefForVariablyModifiedType(S, NewTD);
-  Invalid |= NewTD->isInvalidDecl();
-
-  bool Redeclaration = false;
-
-  NamedDecl *NewND;
-  if (TemplateParamLists.size()) {
-    TypeAliasTemplateDecl *OldDecl = nullptr;
-    TemplateParameterList *OldTemplateParams = nullptr;
-
-    if (TemplateParamLists.size() != 1) {
-      Diag(UsingLoc, diag::err_alias_template_extra_headers)
-        << SourceRange(TemplateParamLists[1]->getTemplateLoc(),
-         TemplateParamLists[TemplateParamLists.size()-1]->getRAngleLoc());
-    }
-    TemplateParameterList *TemplateParams = TemplateParamLists[0];
-
-    // Check that we can declare a template here.
-    if (CheckTemplateDeclScope(S, TemplateParams))
-      return nullptr;
-
-    // Only consider previous declarations in the same scope.
-    FilterLookupForScope(Previous, CurContext, S, /*ConsiderLinkage*/false,
-                         /*ExplicitInstantiationOrSpecialization*/false);
-    if (!Previous.empty()) {
-      Redeclaration = true;
-
-      OldDecl = Previous.getAsSingle<TypeAliasTemplateDecl>();
-      if (!OldDecl && !Invalid) {
-        Diag(UsingLoc, diag::err_redefinition_different_kind)
-          << Name.Identifier;
-
-        NamedDecl *OldD = Previous.getRepresentativeDecl();
-        if (OldD->getLocation().isValid())
-          Diag(OldD->getLocation(), diag::note_previous_definition);
-
-        Invalid = true;
-      }
-
-      if (!Invalid && OldDecl && !OldDecl->isInvalidDecl()) {
-        if (TemplateParameterListsAreEqual(TemplateParams,
-                                           OldDecl->getTemplateParameters(),
-                                           /*Complain=*/true,
-                                           TPL_TemplateMatch))
-          OldTemplateParams =
-              OldDecl->getMostRecentDecl()->getTemplateParameters();
-        else
-          Invalid = true;
-
-        TypeAliasDecl *OldTD = OldDecl->getTemplatedDecl();
-        if (!Invalid &&
-            !Context.hasSameType(OldTD->getUnderlyingType(),
-                                 NewTD->getUnderlyingType())) {
-          // FIXME: The C++0x standard does not clearly say this is ill-formed,
-          // but we can't reasonably accept it.
-          Diag(NewTD->getLocation(), diag::err_redefinition_different_typedef)
-            << 2 << NewTD->getUnderlyingType() << OldTD->getUnderlyingType();
-          if (OldTD->getLocation().isValid())
-            Diag(OldTD->getLocation(), diag::note_previous_definition);
-          Invalid = true;
-        }
-      }
-    }
-
-    // Merge any previous default template arguments into our parameters,
-    // and check the parameter list.
-    if (CheckTemplateParameterList(TemplateParams, OldTemplateParams,
-                                   TPC_TypeAliasTemplate))
-      return nullptr;
-
-    TypeAliasTemplateDecl *NewDecl =
-      TypeAliasTemplateDecl::Create(Context, CurContext, UsingLoc,
-                                    Name.Identifier, TemplateParams,
-                                    NewTD);
-    NewTD->setDescribedAliasTemplate(NewDecl);
-
-    NewDecl->setAccess(AS);
-
-    if (Invalid)
-      NewDecl->setInvalidDecl();
-    else if (OldDecl) {
-      NewDecl->setPreviousDecl(OldDecl);
-      CheckRedeclarationModuleOwnership(NewDecl, OldDecl);
-    }
-
-    NewND = NewDecl;
-  } else {
-    if (auto *TD = dyn_cast_or_null<TagDecl>(DeclFromDeclSpec)) {
-      setTagNameForLinkagePurposes(TD, NewTD);
-      handleTagNumbering(TD, S);
-    }
-    ActOnTypedefNameDecl(S, CurContext, NewTD, Previous, Redeclaration);
-    NewND = NewTD;
-  }
-
-  PushOnScopeChains(NewND, S);
-  ActOnDocumentableDecl(NewND);
-  return NewND;
-}
-
-Decl *Sema::ActOnNamespaceAliasDef(Scope *S, SourceLocation NamespaceLoc,
-                                   SourceLocation AliasLoc,
-                                   IdentifierInfo *Alias, CXXScopeSpec &SS,
-                                   SourceLocation IdentLoc,
-                                   IdentifierInfo *Ident) {
-
-  // Lookup the namespace name.
-  LookupResult R(*this, Ident, IdentLoc, LookupNamespaceName);
-  LookupParsedName(R, S, &SS);
-
-  if (R.isAmbiguous())
-    return nullptr;
-
-  if (R.empty()) {
-    if (!TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, Ident)) {
-      Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
-      return nullptr;
-    }
-  }
-  assert(!R.isAmbiguous() && !R.empty());
-  NamedDecl *ND = R.getRepresentativeDecl();
-
-  // Check if we have a previous declaration with the same name.
-  LookupResult PrevR(*this, Alias, AliasLoc, LookupOrdinaryName,
-                     ForVisibleRedeclaration);
-  LookupName(PrevR, S);
-
-  // Check we're not shadowing a template parameter.
-  if (PrevR.isSingleResult() && PrevR.getFoundDecl()->isTemplateParameter()) {
-    DiagnoseTemplateParameterShadow(AliasLoc, PrevR.getFoundDecl());
-    PrevR.clear();
-  }
-
-  // Filter out any other lookup result from an enclosing scope.
-  FilterLookupForScope(PrevR, CurContext, S, /*ConsiderLinkage*/false,
-                       /*AllowInlineNamespace*/false);
-
-  // Find the previous declaration and check that we can redeclare it.
-  NamespaceAliasDecl *Prev = nullptr;
-  if (PrevR.isSingleResult()) {
-    NamedDecl *PrevDecl = PrevR.getRepresentativeDecl();
-    if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
-      // We already have an alias with the same name that points to the same
-      // namespace; check that it matches.
-      if (AD->getNamespace()->Equals(getNamespaceDecl(ND))) {
-        Prev = AD;
-      } else if (isVisible(PrevDecl)) {
-        Diag(AliasLoc, diag::err_redefinition_different_namespace_alias)
-          << Alias;
-        Diag(AD->getLocation(), diag::note_previous_namespace_alias)
-          << AD->getNamespace();
-        return nullptr;
-      }
-    } else if (isVisible(PrevDecl)) {
-      unsigned DiagID = isa<NamespaceDecl>(PrevDecl->getUnderlyingDecl())
-                            ? diag::err_redefinition
-                            : diag::err_redefinition_different_kind;
-      Diag(AliasLoc, DiagID) << Alias;
-      Diag(PrevDecl->getLocation(), diag::note_previous_definition);
-      return nullptr;
-    }
-  }
-
-  // The use of a nested name specifier may trigger deprecation warnings.
-  DiagnoseUseOfDecl(ND, IdentLoc);
-
-  NamespaceAliasDecl *AliasDecl =
-    NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc,
-                               Alias, SS.getWithLocInContext(Context),
-                               IdentLoc, ND);
-  if (Prev)
-    AliasDecl->setPreviousDecl(Prev);
-
-  PushOnScopeChains(AliasDecl, S);
-  return AliasDecl;
-}
-
-namespace {
-struct SpecialMemberExceptionSpecInfo
-    : SpecialMemberVisitor<SpecialMemberExceptionSpecInfo> {
-  SourceLocation Loc;
-  Sema::ImplicitExceptionSpecification ExceptSpec;
-
-  SpecialMemberExceptionSpecInfo(Sema &S, CXXMethodDecl *MD,
-                                 Sema::CXXSpecialMember CSM,
-                                 Sema::InheritedConstructorInfo *ICI,
-                                 SourceLocation Loc)
-      : SpecialMemberVisitor(S, MD, CSM, ICI), Loc(Loc), ExceptSpec(S) {}
-
-  bool visitBase(CXXBaseSpecifier *Base);
-  bool visitField(FieldDecl *FD);
-
-  void visitClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
-                           unsigned Quals);
-
-  void visitSubobjectCall(Subobject Subobj,
-                          Sema::SpecialMemberOverloadResult SMOR);
-};
-}
-
-bool SpecialMemberExceptionSpecInfo::visitBase(CXXBaseSpecifier *Base) {
-  auto *RT = Base->getType()->getAs<RecordType>();
-  if (!RT)
-    return false;
-
-  auto *BaseClass = cast<CXXRecordDecl>(RT->getDecl());
-  Sema::SpecialMemberOverloadResult SMOR = lookupInheritedCtor(BaseClass);
-  if (auto *BaseCtor = SMOR.getMethod()) {
-    visitSubobjectCall(Base, BaseCtor);
-    return false;
-  }
-
-  visitClassSubobject(BaseClass, Base, 0);
-  return false;
-}
-
-bool SpecialMemberExceptionSpecInfo::visitField(FieldDecl *FD) {
-  if (CSM == Sema::CXXDefaultConstructor && FD->hasInClassInitializer()) {
-    Expr *E = FD->getInClassInitializer();
-    if (!E)
-      // FIXME: It's a little wasteful to build and throw away a
-      // CXXDefaultInitExpr here.
-      // FIXME: We should have a single context note pointing at Loc, and
-      // this location should be MD->getLocation() instead, since that's
-      // the location where we actually use the default init expression.
-      E = S.BuildCXXDefaultInitExpr(Loc, FD).get();
-    if (E)
-      ExceptSpec.CalledExpr(E);
-  } else if (auto *RT = S.Context.getBaseElementType(FD->getType())
-                            ->getAs<RecordType>()) {
-    visitClassSubobject(cast<CXXRecordDecl>(RT->getDecl()), FD,
-                        FD->getType().getCVRQualifiers());
-  }
-  return false;
-}
-
-void SpecialMemberExceptionSpecInfo::visitClassSubobject(CXXRecordDecl *Class,
-                                                         Subobject Subobj,
-                                                         unsigned Quals) {
-  FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
-  bool IsMutable = Field && Field->isMutable();
-  visitSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable));
-}
-
-void SpecialMemberExceptionSpecInfo::visitSubobjectCall(
-    Subobject Subobj, Sema::SpecialMemberOverloadResult SMOR) {
-  // Note, if lookup fails, it doesn't matter what exception specification we
-  // choose because the special member will be deleted.
-  if (CXXMethodDecl *MD = SMOR.getMethod())
-    ExceptSpec.CalledDecl(getSubobjectLoc(Subobj), MD);
-}
-
-namespace {
-/// RAII object to register a special member as being currently declared.
-struct ComputingExceptionSpec {
-  Sema &S;
-
-  ComputingExceptionSpec(Sema &S, CXXMethodDecl *MD, SourceLocation Loc)
-      : S(S) {
-    Sema::CodeSynthesisContext Ctx;
-    Ctx.Kind = Sema::CodeSynthesisContext::ExceptionSpecEvaluation;
-    Ctx.PointOfInstantiation = Loc;
-    Ctx.Entity = MD;
-    S.pushCodeSynthesisContext(Ctx);
-  }
-  ~ComputingExceptionSpec() {
-    S.popCodeSynthesisContext();
-  }
-};
-}
-
-static Sema::ImplicitExceptionSpecification
-ComputeDefaultedSpecialMemberExceptionSpec(
-    Sema &S, SourceLocation Loc, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
-    Sema::InheritedConstructorInfo *ICI) {
-  ComputingExceptionSpec CES(S, MD, Loc);
-
-  CXXRecordDecl *ClassDecl = MD->getParent();
-
-  // C++ [except.spec]p14:
-  //   An implicitly declared special member function (Clause 12) shall have an
-  //   exception-specification. [...]
-  SpecialMemberExceptionSpecInfo Info(S, MD, CSM, ICI, MD->getLocation());
-  if (ClassDecl->isInvalidDecl())
-    return Info.ExceptSpec;
-
-  // FIXME: If this diagnostic fires, we're probably missing a check for
-  // attempting to resolve an exception specification before it's known
-  // at a higher level.
-  if (S.RequireCompleteType(MD->getLocation(),
-                            S.Context.getRecordType(ClassDecl),
-                            diag::err_exception_spec_incomplete_type))
-    return Info.ExceptSpec;
-
-  // C++1z [except.spec]p7:
-  //   [Look for exceptions thrown by] a constructor selected [...] to
-  //   initialize a potentially constructed subobject,
-  // C++1z [except.spec]p8:
-  //   The exception specification for an implicitly-declared destructor, or a
-  //   destructor without a noexcept-specifier, is potentially-throwing if and
-  //   only if any of the destructors for any of its potentially constructed
-  //   subojects is potentially throwing.
-  // FIXME: We respect the first rule but ignore the "potentially constructed"
-  // in the second rule to resolve a core issue (no number yet) that would have
-  // us reject:
-  //   struct A { virtual void f() = 0; virtual ~A() noexcept(false) = 0; };
-  //   struct B : A {};
-  //   struct C : B { void f(); };
-  // ... due to giving B::~B() a non-throwing exception specification.
-  Info.visit(Info.IsConstructor ? Info.VisitPotentiallyConstructedBases
-                                : Info.VisitAllBases);
-
-  return Info.ExceptSpec;
-}
-
-namespace {
-/// RAII object to register a special member as being currently declared.
-struct DeclaringSpecialMember {
-  Sema &S;
-  Sema::SpecialMemberDecl D;
-  Sema::ContextRAII SavedContext;
-  bool WasAlreadyBeingDeclared;
-
-  DeclaringSpecialMember(Sema &S, CXXRecordDecl *RD, Sema::CXXSpecialMember CSM)
-      : S(S), D(RD, CSM), SavedContext(S, RD) {
-    WasAlreadyBeingDeclared = !S.SpecialMembersBeingDeclared.insert(D).second;
-    if (WasAlreadyBeingDeclared)
-      // This almost never happens, but if it does, ensure that our cache
-      // doesn't contain a stale result.
-      S.SpecialMemberCache.clear();
-    else {
-      // Register a note to be produced if we encounter an error while
-      // declaring the special member.
-      Sema::CodeSynthesisContext Ctx;
-      Ctx.Kind = Sema::CodeSynthesisContext::DeclaringSpecialMember;
-      // FIXME: We don't have a location to use here. Using the class's
-      // location maintains the fiction that we declare all special members
-      // with the class, but (1) it's not clear that lying about that helps our
-      // users understand what's going on, and (2) there may be outer contexts
-      // on the stack (some of which are relevant) and printing them exposes
-      // our lies.
-      Ctx.PointOfInstantiation = RD->getLocation();
-      Ctx.Entity = RD;
-      Ctx.SpecialMember = CSM;
-      S.pushCodeSynthesisContext(Ctx);
-    }
-  }
-  ~DeclaringSpecialMember() {
-    if (!WasAlreadyBeingDeclared) {
-      S.SpecialMembersBeingDeclared.erase(D);
-      S.popCodeSynthesisContext();
-    }
-  }
-
-  /// Are we already trying to declare this special member?
-  bool isAlreadyBeingDeclared() const {
-    return WasAlreadyBeingDeclared;
-  }
-};
-}
-
-void Sema::CheckImplicitSpecialMemberDeclaration(Scope *S, FunctionDecl *FD) {
-  // Look up any existing declarations, but don't trigger declaration of all
-  // implicit special members with this name.
-  DeclarationName Name = FD->getDeclName();
-  LookupResult R(*this, Name, SourceLocation(), LookupOrdinaryName,
-                 ForExternalRedeclaration);
-  for (auto *D : FD->getParent()->lookup(Name))
-    if (auto *Acceptable = R.getAcceptableDecl(D))
-      R.addDecl(Acceptable);
-  R.resolveKind();
-  R.suppressDiagnostics();
-
-  CheckFunctionDeclaration(S, FD, R, /*IsMemberSpecialization*/false);
-}
-
-void Sema::setupImplicitSpecialMemberType(CXXMethodDecl *SpecialMem,
-                                          QualType ResultTy,
-                                          ArrayRef<QualType> Args) {
-  // Build an exception specification pointing back at this constructor.
-  FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, SpecialMem);
-
-  if (getLangOpts().OpenCLCPlusPlus) {
-    // OpenCL: Implicitly defaulted special member are of the generic address
-    // space.
-    EPI.TypeQuals.addAddressSpace(LangAS::opencl_generic);
-  }
-
-  auto QT = Context.getFunctionType(ResultTy, Args, EPI);
-  SpecialMem->setType(QT);
-}
-
-CXXConstructorDecl *Sema::DeclareImplicitDefaultConstructor(
-                                                     CXXRecordDecl *ClassDecl) {
-  // C++ [class.ctor]p5:
-  //   A default constructor for a class X is a constructor of class X
-  //   that can be called without an argument. If there is no
-  //   user-declared constructor for class X, a default constructor is
-  //   implicitly declared. An implicitly-declared default constructor
-  //   is an inline public member of its class.
-  assert(ClassDecl->needsImplicitDefaultConstructor() &&
-         "Should not build implicit default constructor!");
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXDefaultConstructor);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
-                                                     CXXDefaultConstructor,
-                                                     false);
-
-  // Create the actual constructor declaration.
-  CanQualType ClassType
-    = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationName Name
-    = Context.DeclarationNames.getCXXConstructorName(ClassType);
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-  CXXConstructorDecl *DefaultCon = CXXConstructorDecl::Create(
-      Context, ClassDecl, ClassLoc, NameInfo, /*Type*/QualType(),
-      /*TInfo=*/nullptr, /*isExplicit=*/false, /*isInline=*/true,
-      /*isImplicitlyDeclared=*/true, Constexpr);
-  DefaultCon->setAccess(AS_public);
-  DefaultCon->setDefaulted();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDefaultConstructor,
-                                            DefaultCon,
-                                            /* ConstRHS */ false,
-                                            /* Diagnose */ false);
-  }
-
-  setupImplicitSpecialMemberType(DefaultCon, Context.VoidTy, None);
-
-  // We don't need to use SpecialMemberIsTrivial here; triviality for default
-  // constructors is easy to compute.
-  DefaultCon->setTrivial(ClassDecl->hasTrivialDefaultConstructor());
-
-  // Note that we have declared this constructor.
-  ++ASTContext::NumImplicitDefaultConstructorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, DefaultCon);
-
-  if (ShouldDeleteSpecialMember(DefaultCon, CXXDefaultConstructor))
-    SetDeclDeleted(DefaultCon, ClassLoc);
-
-  if (S)
-    PushOnScopeChains(DefaultCon, S, false);
-  ClassDecl->addDecl(DefaultCon);
-
-  return DefaultCon;
-}
-
-void Sema::DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
-                                            CXXConstructorDecl *Constructor) {
-  assert((Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
-          !Constructor->doesThisDeclarationHaveABody() &&
-          !Constructor->isDeleted()) &&
-    "DefineImplicitDefaultConstructor - call it for implicit default ctor");
-  if (Constructor->willHaveBody() || Constructor->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = Constructor->getParent();
-  assert(ClassDecl && "DefineImplicitDefaultConstructor - invalid constructor");
-
-  SynthesizedFunctionScope Scope(*this, Constructor);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       Constructor->getType()->castAs<FunctionProtoType>());
-  MarkVTableUsed(CurrentLocation, ClassDecl);
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  if (SetCtorInitializers(Constructor, /*AnyErrors=*/false)) {
-    Constructor->setInvalidDecl();
-    return;
-  }
-
-  SourceLocation Loc = Constructor->getEndLoc().isValid()
-                           ? Constructor->getEndLoc()
-                           : Constructor->getLocation();
-  Constructor->setBody(new (Context) CompoundStmt(Loc));
-  Constructor->markUsed(Context);
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(Constructor);
-  }
-
-  DiagnoseUninitializedFields(*this, Constructor);
-}
-
-void Sema::ActOnFinishDelayedMemberInitializers(Decl *D) {
-  // Perform any delayed checks on exception specifications.
-  CheckDelayedMemberExceptionSpecs();
-}
-
-/// Find or create the fake constructor we synthesize to model constructing an
-/// object of a derived class via a constructor of a base class.
-CXXConstructorDecl *
-Sema::findInheritingConstructor(SourceLocation Loc,
-                                CXXConstructorDecl *BaseCtor,
-                                ConstructorUsingShadowDecl *Shadow) {
-  CXXRecordDecl *Derived = Shadow->getParent();
-  SourceLocation UsingLoc = Shadow->getLocation();
-
-  // FIXME: Add a new kind of DeclarationName for an inherited constructor.
-  // For now we use the name of the base class constructor as a member of the
-  // derived class to indicate a (fake) inherited constructor name.
-  DeclarationName Name = BaseCtor->getDeclName();
-
-  // Check to see if we already have a fake constructor for this inherited
-  // constructor call.
-  for (NamedDecl *Ctor : Derived->lookup(Name))
-    if (declaresSameEntity(cast<CXXConstructorDecl>(Ctor)
-                               ->getInheritedConstructor()
-                               .getConstructor(),
-                           BaseCtor))
-      return cast<CXXConstructorDecl>(Ctor);
-
-  DeclarationNameInfo NameInfo(Name, UsingLoc);
-  TypeSourceInfo *TInfo =
-      Context.getTrivialTypeSourceInfo(BaseCtor->getType(), UsingLoc);
-  FunctionProtoTypeLoc ProtoLoc =
-      TInfo->getTypeLoc().IgnoreParens().castAs<FunctionProtoTypeLoc>();
-
-  // Check the inherited constructor is valid and find the list of base classes
-  // from which it was inherited.
-  InheritedConstructorInfo ICI(*this, Loc, Shadow);
-
-  bool Constexpr =
-      BaseCtor->isConstexpr() &&
-      defaultedSpecialMemberIsConstexpr(*this, Derived, CXXDefaultConstructor,
-                                        false, BaseCtor, &ICI);
-
-  CXXConstructorDecl *DerivedCtor = CXXConstructorDecl::Create(
-      Context, Derived, UsingLoc, NameInfo, TInfo->getType(), TInfo,
-      BaseCtor->isExplicit(), /*Inline=*/true,
-      /*ImplicitlyDeclared=*/true, Constexpr,
-      InheritedConstructor(Shadow, BaseCtor));
-  if (Shadow->isInvalidDecl())
-    DerivedCtor->setInvalidDecl();
-
-  // Build an unevaluated exception specification for this fake constructor.
-  const FunctionProtoType *FPT = TInfo->getType()->castAs<FunctionProtoType>();
-  FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
-  EPI.ExceptionSpec.Type = EST_Unevaluated;
-  EPI.ExceptionSpec.SourceDecl = DerivedCtor;
-  DerivedCtor->setType(Context.getFunctionType(FPT->getReturnType(),
-                                               FPT->getParamTypes(), EPI));
-
-  // Build the parameter declarations.
-  SmallVector<ParmVarDecl *, 16> ParamDecls;
-  for (unsigned I = 0, N = FPT->getNumParams(); I != N; ++I) {
-    TypeSourceInfo *TInfo =
-        Context.getTrivialTypeSourceInfo(FPT->getParamType(I), UsingLoc);
-    ParmVarDecl *PD = ParmVarDecl::Create(
-        Context, DerivedCtor, UsingLoc, UsingLoc, /*IdentifierInfo=*/nullptr,
-        FPT->getParamType(I), TInfo, SC_None, /*DefaultArg=*/nullptr);
-    PD->setScopeInfo(0, I);
-    PD->setImplicit();
-    // Ensure attributes are propagated onto parameters (this matters for
-    // format, pass_object_size, ...).
-    mergeDeclAttributes(PD, BaseCtor->getParamDecl(I));
-    ParamDecls.push_back(PD);
-    ProtoLoc.setParam(I, PD);
-  }
-
-  // Set up the new constructor.
-  assert(!BaseCtor->isDeleted() && "should not use deleted constructor");
-  DerivedCtor->setAccess(BaseCtor->getAccess());
-  DerivedCtor->setParams(ParamDecls);
-  Derived->addDecl(DerivedCtor);
-
-  if (ShouldDeleteSpecialMember(DerivedCtor, CXXDefaultConstructor, &ICI))
-    SetDeclDeleted(DerivedCtor, UsingLoc);
-
-  return DerivedCtor;
-}
-
-void Sema::NoteDeletedInheritingConstructor(CXXConstructorDecl *Ctor) {
-  InheritedConstructorInfo ICI(*this, Ctor->getLocation(),
-                               Ctor->getInheritedConstructor().getShadowDecl());
-  ShouldDeleteSpecialMember(Ctor, CXXDefaultConstructor, &ICI,
-                            /*Diagnose*/true);
-}
-
-void Sema::DefineInheritingConstructor(SourceLocation CurrentLocation,
-                                       CXXConstructorDecl *Constructor) {
-  CXXRecordDecl *ClassDecl = Constructor->getParent();
-  assert(Constructor->getInheritedConstructor() &&
-         !Constructor->doesThisDeclarationHaveABody() &&
-         !Constructor->isDeleted());
-  if (Constructor->willHaveBody() || Constructor->isInvalidDecl())
-    return;
-
-  // Initializations are performed "as if by a defaulted default constructor",
-  // so enter the appropriate scope.
-  SynthesizedFunctionScope Scope(*this, Constructor);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       Constructor->getType()->castAs<FunctionProtoType>());
-  MarkVTableUsed(CurrentLocation, ClassDecl);
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  ConstructorUsingShadowDecl *Shadow =
-      Constructor->getInheritedConstructor().getShadowDecl();
-  CXXConstructorDecl *InheritedCtor =
-      Constructor->getInheritedConstructor().getConstructor();
-
-  // [class.inhctor.init]p1:
-  //   initialization proceeds as if a defaulted default constructor is used to
-  //   initialize the D object and each base class subobject from which the
-  //   constructor was inherited
-
-  InheritedConstructorInfo ICI(*this, CurrentLocation, Shadow);
-  CXXRecordDecl *RD = Shadow->getParent();
-  SourceLocation InitLoc = Shadow->getLocation();
-
-  // Build explicit initializers for all base classes from which the
-  // constructor was inherited.
-  SmallVector<CXXCtorInitializer*, 8> Inits;
-  for (bool VBase : {false, true}) {
-    for (CXXBaseSpecifier &B : VBase ? RD->vbases() : RD->bases()) {
-      if (B.isVirtual() != VBase)
-        continue;
-
-      auto *BaseRD = B.getType()->getAsCXXRecordDecl();
-      if (!BaseRD)
-        continue;
-
-      auto BaseCtor = ICI.findConstructorForBase(BaseRD, InheritedCtor);
-      if (!BaseCtor.first)
-        continue;
-
-      MarkFunctionReferenced(CurrentLocation, BaseCtor.first);
-      ExprResult Init = new (Context) CXXInheritedCtorInitExpr(
-          InitLoc, B.getType(), BaseCtor.first, VBase, BaseCtor.second);
-
-      auto *TInfo = Context.getTrivialTypeSourceInfo(B.getType(), InitLoc);
-      Inits.push_back(new (Context) CXXCtorInitializer(
-          Context, TInfo, VBase, InitLoc, Init.get(), InitLoc,
-          SourceLocation()));
-    }
-  }
-
-  // We now proceed as if for a defaulted default constructor, with the relevant
-  // initializers replaced.
-
-  if (SetCtorInitializers(Constructor, /*AnyErrors*/false, Inits)) {
-    Constructor->setInvalidDecl();
-    return;
-  }
-
-  Constructor->setBody(new (Context) CompoundStmt(InitLoc));
-  Constructor->markUsed(Context);
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(Constructor);
-  }
-
-  DiagnoseUninitializedFields(*this, Constructor);
-}
-
-CXXDestructorDecl *Sema::DeclareImplicitDestructor(CXXRecordDecl *ClassDecl) {
-  // C++ [class.dtor]p2:
-  //   If a class has no user-declared destructor, a destructor is
-  //   declared implicitly. An implicitly-declared destructor is an
-  //   inline public member of its class.
-  assert(ClassDecl->needsImplicitDestructor());
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXDestructor);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  // Create the actual destructor declaration.
-  CanQualType ClassType
-    = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationName Name
-    = Context.DeclarationNames.getCXXDestructorName(ClassType);
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-  CXXDestructorDecl *Destructor
-      = CXXDestructorDecl::Create(Context, ClassDecl, ClassLoc, NameInfo,
-                                  QualType(), nullptr, /*isInline=*/true,
-                                  /*isImplicitlyDeclared=*/true);
-  Destructor->setAccess(AS_public);
-  Destructor->setDefaulted();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDestructor,
-                                            Destructor,
-                                            /* ConstRHS */ false,
-                                            /* Diagnose */ false);
-  }
-
-  setupImplicitSpecialMemberType(Destructor, Context.VoidTy, None);
-
-  // We don't need to use SpecialMemberIsTrivial here; triviality for
-  // destructors is easy to compute.
-  Destructor->setTrivial(ClassDecl->hasTrivialDestructor());
-  Destructor->setTrivialForCall(ClassDecl->hasAttr<TrivialABIAttr>() ||
-                                ClassDecl->hasTrivialDestructorForCall());
-
-  // Note that we have declared this destructor.
-  ++ASTContext::NumImplicitDestructorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, Destructor);
-
-  // We can't check whether an implicit destructor is deleted before we complete
-  // the definition of the class, because its validity depends on the alignment
-  // of the class. We'll check this from ActOnFields once the class is complete.
-  if (ClassDecl->isCompleteDefinition() &&
-      ShouldDeleteSpecialMember(Destructor, CXXDestructor))
-    SetDeclDeleted(Destructor, ClassLoc);
-
-  // Introduce this destructor into its scope.
-  if (S)
-    PushOnScopeChains(Destructor, S, false);
-  ClassDecl->addDecl(Destructor);
-
-  return Destructor;
-}
-
-void Sema::DefineImplicitDestructor(SourceLocation CurrentLocation,
-                                    CXXDestructorDecl *Destructor) {
-  assert((Destructor->isDefaulted() &&
-          !Destructor->doesThisDeclarationHaveABody() &&
-          !Destructor->isDeleted()) &&
-         "DefineImplicitDestructor - call it for implicit default dtor");
-  if (Destructor->willHaveBody() || Destructor->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = Destructor->getParent();
-  assert(ClassDecl && "DefineImplicitDestructor - invalid destructor");
-
-  SynthesizedFunctionScope Scope(*this, Destructor);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       Destructor->getType()->castAs<FunctionProtoType>());
-  MarkVTableUsed(CurrentLocation, ClassDecl);
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
-                                         Destructor->getParent());
-
-  if (CheckDestructor(Destructor)) {
-    Destructor->setInvalidDecl();
-    return;
-  }
-
-  SourceLocation Loc = Destructor->getEndLoc().isValid()
-                           ? Destructor->getEndLoc()
-                           : Destructor->getLocation();
-  Destructor->setBody(new (Context) CompoundStmt(Loc));
-  Destructor->markUsed(Context);
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(Destructor);
-  }
-}
-
-/// Perform any semantic analysis which needs to be delayed until all
-/// pending class member declarations have been parsed.
-void Sema::ActOnFinishCXXMemberDecls() {
-  // If the context is an invalid C++ class, just suppress these checks.
-  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(CurContext)) {
-    if (Record->isInvalidDecl()) {
-      DelayedOverridingExceptionSpecChecks.clear();
-      DelayedEquivalentExceptionSpecChecks.clear();
-      DelayedDefaultedMemberExceptionSpecs.clear();
-      return;
-    }
-    checkForMultipleExportedDefaultConstructors(*this, Record);
-  }
-}
-
-void Sema::ActOnFinishCXXNonNestedClass(Decl *D) {
-  referenceDLLExportedClassMethods();
-}
-
-void Sema::referenceDLLExportedClassMethods() {
-  if (!DelayedDllExportClasses.empty()) {
-    // Calling ReferenceDllExportedMembers might cause the current function to
-    // be called again, so use a local copy of DelayedDllExportClasses.
-    SmallVector<CXXRecordDecl *, 4> WorkList;
-    std::swap(DelayedDllExportClasses, WorkList);
-    for (CXXRecordDecl *Class : WorkList)
-      ReferenceDllExportedMembers(*this, Class);
-  }
-}
-
-void Sema::AdjustDestructorExceptionSpec(CXXDestructorDecl *Destructor) {
-  assert(getLangOpts().CPlusPlus11 &&
-         "adjusting dtor exception specs was introduced in c++11");
-
-  if (Destructor->isDependentContext())
-    return;
-
-  // C++11 [class.dtor]p3:
-  //   A declaration of a destructor that does not have an exception-
-  //   specification is implicitly considered to have the same exception-
-  //   specification as an implicit declaration.
-  const FunctionProtoType *DtorType = Destructor->getType()->
-                                        getAs<FunctionProtoType>();
-  if (DtorType->hasExceptionSpec())
-    return;
-
-  // Replace the destructor's type, building off the existing one. Fortunately,
-  // the only thing of interest in the destructor type is its extended info.
-  // The return and arguments are fixed.
-  FunctionProtoType::ExtProtoInfo EPI = DtorType->getExtProtoInfo();
-  EPI.ExceptionSpec.Type = EST_Unevaluated;
-  EPI.ExceptionSpec.SourceDecl = Destructor;
-  Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
-
-  // FIXME: If the destructor has a body that could throw, and the newly created
-  // spec doesn't allow exceptions, we should emit a warning, because this
-  // change in behavior can break conforming C++03 programs at runtime.
-  // However, we don't have a body or an exception specification yet, so it
-  // needs to be done somewhere else.
-}
-
-namespace {
-/// An abstract base class for all helper classes used in building the
-//  copy/move operators. These classes serve as factory functions and help us
-//  avoid using the same Expr* in the AST twice.
-class ExprBuilder {
-  ExprBuilder(const ExprBuilder&) = delete;
-  ExprBuilder &operator=(const ExprBuilder&) = delete;
-
-protected:
-  static Expr *assertNotNull(Expr *E) {
-    assert(E && "Expression construction must not fail.");
-    return E;
-  }
-
-public:
-  ExprBuilder() {}
-  virtual ~ExprBuilder() {}
-
-  virtual Expr *build(Sema &S, SourceLocation Loc) const = 0;
-};
-
-class RefBuilder: public ExprBuilder {
-  VarDecl *Var;
-  QualType VarType;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(S.BuildDeclRefExpr(Var, VarType, VK_LValue, Loc).get());
-  }
-
-  RefBuilder(VarDecl *Var, QualType VarType)
-      : Var(Var), VarType(VarType) {}
-};
-
-class ThisBuilder: public ExprBuilder {
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(S.ActOnCXXThis(Loc).getAs<Expr>());
-  }
-};
-
-class CastBuilder: public ExprBuilder {
-  const ExprBuilder &Builder;
-  QualType Type;
-  ExprValueKind Kind;
-  const CXXCastPath &Path;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(S.ImpCastExprToType(Builder.build(S, Loc), Type,
-                                             CK_UncheckedDerivedToBase, Kind,
-                                             &Path).get());
-  }
-
-  CastBuilder(const ExprBuilder &Builder, QualType Type, ExprValueKind Kind,
-              const CXXCastPath &Path)
-      : Builder(Builder), Type(Type), Kind(Kind), Path(Path) {}
-};
-
-class DerefBuilder: public ExprBuilder {
-  const ExprBuilder &Builder;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(
-        S.CreateBuiltinUnaryOp(Loc, UO_Deref, Builder.build(S, Loc)).get());
-  }
-
-  DerefBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
-};
-
-class MemberBuilder: public ExprBuilder {
-  const ExprBuilder &Builder;
-  QualType Type;
-  CXXScopeSpec SS;
-  bool IsArrow;
-  LookupResult &MemberLookup;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(S.BuildMemberReferenceExpr(
-        Builder.build(S, Loc), Type, Loc, IsArrow, SS, SourceLocation(),
-        nullptr, MemberLookup, nullptr, nullptr).get());
-  }
-
-  MemberBuilder(const ExprBuilder &Builder, QualType Type, bool IsArrow,
-                LookupResult &MemberLookup)
-      : Builder(Builder), Type(Type), IsArrow(IsArrow),
-        MemberLookup(MemberLookup) {}
-};
-
-class MoveCastBuilder: public ExprBuilder {
-  const ExprBuilder &Builder;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(CastForMoving(S, Builder.build(S, Loc)));
-  }
-
-  MoveCastBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
-};
-
-class LvalueConvBuilder: public ExprBuilder {
-  const ExprBuilder &Builder;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(
-        S.DefaultLvalueConversion(Builder.build(S, Loc)).get());
-  }
-
-  LvalueConvBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
-};
-
-class SubscriptBuilder: public ExprBuilder {
-  const ExprBuilder &Base;
-  const ExprBuilder &Index;
-
-public:
-  Expr *build(Sema &S, SourceLocation Loc) const override {
-    return assertNotNull(S.CreateBuiltinArraySubscriptExpr(
-        Base.build(S, Loc), Loc, Index.build(S, Loc), Loc).get());
-  }
-
-  SubscriptBuilder(const ExprBuilder &Base, const ExprBuilder &Index)
-      : Base(Base), Index(Index) {}
-};
-
-} // end anonymous namespace
-
-/// When generating a defaulted copy or move assignment operator, if a field
-/// should be copied with __builtin_memcpy rather than via explicit assignments,
-/// do so. This optimization only applies for arrays of scalars, and for arrays
-/// of class type where the selected copy/move-assignment operator is trivial.
-static StmtResult
-buildMemcpyForAssignmentOp(Sema &S, SourceLocation Loc, QualType T,
-                           const ExprBuilder &ToB, const ExprBuilder &FromB) {
-  // Compute the size of the memory buffer to be copied.
-  QualType SizeType = S.Context.getSizeType();
-  llvm::APInt Size(S.Context.getTypeSize(SizeType),
-                   S.Context.getTypeSizeInChars(T).getQuantity());
-
-  // Take the address of the field references for "from" and "to". We
-  // directly construct UnaryOperators here because semantic analysis
-  // does not permit us to take the address of an xvalue.
-  Expr *From = FromB.build(S, Loc);
-  From = new (S.Context) UnaryOperator(From, UO_AddrOf,
-                         S.Context.getPointerType(From->getType()),
-                         VK_RValue, OK_Ordinary, Loc, false);
-  Expr *To = ToB.build(S, Loc);
-  To = new (S.Context) UnaryOperator(To, UO_AddrOf,
-                       S.Context.getPointerType(To->getType()),
-                       VK_RValue, OK_Ordinary, Loc, false);
-
-  const Type *E = T->getBaseElementTypeUnsafe();
-  bool NeedsCollectableMemCpy =
-    E->isRecordType() && E->getAs<RecordType>()->getDecl()->hasObjectMember();
-
-  // Create a reference to the __builtin_objc_memmove_collectable function
-  StringRef MemCpyName = NeedsCollectableMemCpy ?
-    "__builtin_objc_memmove_collectable" :
-    "__builtin_memcpy";
-  LookupResult R(S, &S.Context.Idents.get(MemCpyName), Loc,
-                 Sema::LookupOrdinaryName);
-  S.LookupName(R, S.TUScope, true);
-
-  FunctionDecl *MemCpy = R.getAsSingle<FunctionDecl>();
-  if (!MemCpy)
-    // Something went horribly wrong earlier, and we will have complained
-    // about it.
-    return StmtError();
-
-  ExprResult MemCpyRef = S.BuildDeclRefExpr(MemCpy, S.Context.BuiltinFnTy,
-                                            VK_RValue, Loc, nullptr);
-  assert(MemCpyRef.isUsable() && "Builtin reference cannot fail");
-
-  Expr *CallArgs[] = {
-    To, From, IntegerLiteral::Create(S.Context, Size, SizeType, Loc)
-  };
-  ExprResult Call = S.ActOnCallExpr(/*Scope=*/nullptr, MemCpyRef.get(),
-                                    Loc, CallArgs, Loc);
-
-  assert(!Call.isInvalid() && "Call to __builtin_memcpy cannot fail!");
-  return Call.getAs<Stmt>();
-}
-
-/// Builds a statement that copies/moves the given entity from \p From to
-/// \c To.
-///
-/// This routine is used to copy/move the members of a class with an
-/// implicitly-declared copy/move assignment operator. When the entities being
-/// copied are arrays, this routine builds for loops to copy them.
-///
-/// \param S The Sema object used for type-checking.
-///
-/// \param Loc The location where the implicit copy/move is being generated.
-///
-/// \param T The type of the expressions being copied/moved. Both expressions
-/// must have this type.
-///
-/// \param To The expression we are copying/moving to.
-///
-/// \param From The expression we are copying/moving from.
-///
-/// \param CopyingBaseSubobject Whether we're copying/moving a base subobject.
-/// Otherwise, it's a non-static member subobject.
-///
-/// \param Copying Whether we're copying or moving.
-///
-/// \param Depth Internal parameter recording the depth of the recursion.
-///
-/// \returns A statement or a loop that copies the expressions, or StmtResult(0)
-/// if a memcpy should be used instead.
-static StmtResult
-buildSingleCopyAssignRecursively(Sema &S, SourceLocation Loc, QualType T,
-                                 const ExprBuilder &To, const ExprBuilder &From,
-                                 bool CopyingBaseSubobject, bool Copying,
-                                 unsigned Depth = 0) {
-  // C++11 [class.copy]p28:
-  //   Each subobject is assigned in the manner appropriate to its type:
-  //
-  //     - if the subobject is of class type, as if by a call to operator= with
-  //       the subobject as the object expression and the corresponding
-  //       subobject of x as a single function argument (as if by explicit
-  //       qualification; that is, ignoring any possible virtual overriding
-  //       functions in more derived classes);
-  //
-  // C++03 [class.copy]p13:
-  //     - if the subobject is of class type, the copy assignment operator for
-  //       the class is used (as if by explicit qualification; that is,
-  //       ignoring any possible virtual overriding functions in more derived
-  //       classes);
-  if (const RecordType *RecordTy = T->getAs<RecordType>()) {
-    CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
-
-    // Look for operator=.
-    DeclarationName Name
-      = S.Context.DeclarationNames.getCXXOperatorName(OO_Equal);
-    LookupResult OpLookup(S, Name, Loc, Sema::LookupOrdinaryName);
-    S.LookupQualifiedName(OpLookup, ClassDecl, false);
-
-    // Prior to C++11, filter out any result that isn't a copy/move-assignment
-    // operator.
-    if (!S.getLangOpts().CPlusPlus11) {
-      LookupResult::Filter F = OpLookup.makeFilter();
-      while (F.hasNext()) {
-        NamedDecl *D = F.next();
-        if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
-          if (Method->isCopyAssignmentOperator() ||
-              (!Copying && Method->isMoveAssignmentOperator()))
-            continue;
-
-        F.erase();
-      }
-      F.done();
-    }
-
-    // Suppress the protected check (C++ [class.protected]) for each of the
-    // assignment operators we found. This strange dance is required when
-    // we're assigning via a base classes's copy-assignment operator. To
-    // ensure that we're getting the right base class subobject (without
-    // ambiguities), we need to cast "this" to that subobject type; to
-    // ensure that we don't go through the virtual call mechanism, we need
-    // to qualify the operator= name with the base class (see below). However,
-    // this means that if the base class has a protected copy assignment
-    // operator, the protected member access check will fail. So, we
-    // rewrite "protected" access to "public" access in this case, since we
-    // know by construction that we're calling from a derived class.
-    if (CopyingBaseSubobject) {
-      for (LookupResult::iterator L = OpLookup.begin(), LEnd = OpLookup.end();
-           L != LEnd; ++L) {
-        if (L.getAccess() == AS_protected)
-          L.setAccess(AS_public);
-      }
-    }
-
-    // Create the nested-name-specifier that will be used to qualify the
-    // reference to operator=; this is required to suppress the virtual
-    // call mechanism.
-    CXXScopeSpec SS;
-    const Type *CanonicalT = S.Context.getCanonicalType(T.getTypePtr());
-    SS.MakeTrivial(S.Context,
-                   NestedNameSpecifier::Create(S.Context, nullptr, false,
-                                               CanonicalT),
-                   Loc);
-
-    // Create the reference to operator=.
-    ExprResult OpEqualRef
-      = S.BuildMemberReferenceExpr(To.build(S, Loc), T, Loc, /*isArrow=*/false,
-                                   SS, /*TemplateKWLoc=*/SourceLocation(),
-                                   /*FirstQualifierInScope=*/nullptr,
-                                   OpLookup,
-                                   /*TemplateArgs=*/nullptr, /*S*/nullptr,
-                                   /*SuppressQualifierCheck=*/true);
-    if (OpEqualRef.isInvalid())
-      return StmtError();
-
-    // Build the call to the assignment operator.
-
-    Expr *FromInst = From.build(S, Loc);
-    ExprResult Call = S.BuildCallToMemberFunction(/*Scope=*/nullptr,
-                                                  OpEqualRef.getAs<Expr>(),
-                                                  Loc, FromInst, Loc);
-    if (Call.isInvalid())
-      return StmtError();
-
-    // If we built a call to a trivial 'operator=' while copying an array,
-    // bail out. We'll replace the whole shebang with a memcpy.
-    CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(Call.get());
-    if (CE && CE->getMethodDecl()->isTrivial() && Depth)
-      return StmtResult((Stmt*)nullptr);
-
-    // Convert to an expression-statement, and clean up any produced
-    // temporaries.
-    return S.ActOnExprStmt(Call);
-  }
-
-  //     - if the subobject is of scalar type, the built-in assignment
-  //       operator is used.
-  const ConstantArrayType *ArrayTy = S.Context.getAsConstantArrayType(T);
-  if (!ArrayTy) {
-    ExprResult Assignment = S.CreateBuiltinBinOp(
-        Loc, BO_Assign, To.build(S, Loc), From.build(S, Loc));
-    if (Assignment.isInvalid())
-      return StmtError();
-    return S.ActOnExprStmt(Assignment);
-  }
-
-  //     - if the subobject is an array, each element is assigned, in the
-  //       manner appropriate to the element type;
-
-  // Construct a loop over the array bounds, e.g.,
-  //
-  //   for (__SIZE_TYPE__ i0 = 0; i0 != array-size; ++i0)
-  //
-  // that will copy each of the array elements.
-  QualType SizeType = S.Context.getSizeType();
-
-  // Create the iteration variable.
-  IdentifierInfo *IterationVarName = nullptr;
-  {
-    SmallString<8> Str;
-    llvm::raw_svector_ostream OS(Str);
-    OS << "__i" << Depth;
-    IterationVarName = &S.Context.Idents.get(OS.str());
-  }
-  VarDecl *IterationVar = VarDecl::Create(S.Context, S.CurContext, Loc, Loc,
-                                          IterationVarName, SizeType,
-                            S.Context.getTrivialTypeSourceInfo(SizeType, Loc),
-                                          SC_None);
-
-  // Initialize the iteration variable to zero.
-  llvm::APInt Zero(S.Context.getTypeSize(SizeType), 0);
-  IterationVar->setInit(IntegerLiteral::Create(S.Context, Zero, SizeType, Loc));
-
-  // Creates a reference to the iteration variable.
-  RefBuilder IterationVarRef(IterationVar, SizeType);
-  LvalueConvBuilder IterationVarRefRVal(IterationVarRef);
-
-  // Create the DeclStmt that holds the iteration variable.
-  Stmt *InitStmt = new (S.Context) DeclStmt(DeclGroupRef(IterationVar),Loc,Loc);
-
-  // Subscript the "from" and "to" expressions with the iteration variable.
-  SubscriptBuilder FromIndexCopy(From, IterationVarRefRVal);
-  MoveCastBuilder FromIndexMove(FromIndexCopy);
-  const ExprBuilder *FromIndex;
-  if (Copying)
-    FromIndex = &FromIndexCopy;
-  else
-    FromIndex = &FromIndexMove;
-
-  SubscriptBuilder ToIndex(To, IterationVarRefRVal);
-
-  // Build the copy/move for an individual element of the array.
-  StmtResult Copy =
-    buildSingleCopyAssignRecursively(S, Loc, ArrayTy->getElementType(),
-                                     ToIndex, *FromIndex, CopyingBaseSubobject,
-                                     Copying, Depth + 1);
-  // Bail out if copying fails or if we determined that we should use memcpy.
-  if (Copy.isInvalid() || !Copy.get())
-    return Copy;
-
-  // Create the comparison against the array bound.
-  llvm::APInt Upper
-    = ArrayTy->getSize().zextOrTrunc(S.Context.getTypeSize(SizeType));
-  Expr *Comparison
-    = new (S.Context) BinaryOperator(IterationVarRefRVal.build(S, Loc),
-                     IntegerLiteral::Create(S.Context, Upper, SizeType, Loc),
-                                     BO_NE, S.Context.BoolTy,
-                                     VK_RValue, OK_Ordinary, Loc, FPOptions());
-
-  // Create the pre-increment of the iteration variable. We can determine
-  // whether the increment will overflow based on the value of the array
-  // bound.
-  Expr *Increment = new (S.Context)
-      UnaryOperator(IterationVarRef.build(S, Loc), UO_PreInc, SizeType,
-                    VK_LValue, OK_Ordinary, Loc, Upper.isMaxValue());
-
-  // Construct the loop that copies all elements of this array.
-  return S.ActOnForStmt(
-      Loc, Loc, InitStmt,
-      S.ActOnCondition(nullptr, Loc, Comparison, Sema::ConditionKind::Boolean),
-      S.MakeFullDiscardedValueExpr(Increment), Loc, Copy.get());
-}
-
-static StmtResult
-buildSingleCopyAssign(Sema &S, SourceLocation Loc, QualType T,
-                      const ExprBuilder &To, const ExprBuilder &From,
-                      bool CopyingBaseSubobject, bool Copying) {
-  // Maybe we should use a memcpy?
-  if (T->isArrayType() && !T.isConstQualified() && !T.isVolatileQualified() &&
-      T.isTriviallyCopyableType(S.Context))
-    return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
-
-  StmtResult Result(buildSingleCopyAssignRecursively(S, Loc, T, To, From,
-                                                     CopyingBaseSubobject,
-                                                     Copying, 0));
-
-  // If we ended up picking a trivial assignment operator for an array of a
-  // non-trivially-copyable class type, just emit a memcpy.
-  if (!Result.isInvalid() && !Result.get())
-    return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
-
-  return Result;
-}
-
-CXXMethodDecl *Sema::DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl) {
-  // Note: The following rules are largely analoguous to the copy
-  // constructor rules. Note that virtual bases are not taken into account
-  // for determining the argument type of the operator. Note also that
-  // operators taking an object instead of a reference are allowed.
-  assert(ClassDecl->needsImplicitCopyAssignment());
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyAssignment);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  QualType ArgType = Context.getTypeDeclType(ClassDecl);
-  QualType RetType = Context.getLValueReferenceType(ArgType);
-  bool Const = ClassDecl->implicitCopyAssignmentHasConstParam();
-  if (Const)
-    ArgType = ArgType.withConst();
-
-  if (Context.getLangOpts().OpenCLCPlusPlus)
-    ArgType = Context.getAddrSpaceQualType(ArgType, LangAS::opencl_generic);
-
-  ArgType = Context.getLValueReferenceType(ArgType);
-
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
-                                                     CXXCopyAssignment,
-                                                     Const);
-
-  //   An implicitly-declared copy assignment operator is an inline public
-  //   member of its class.
-  DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-  CXXMethodDecl *CopyAssignment =
-      CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
-                            /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
-                            /*isInline=*/true, Constexpr, SourceLocation());
-  CopyAssignment->setAccess(AS_public);
-  CopyAssignment->setDefaulted();
-  CopyAssignment->setImplicit();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyAssignment,
-                                            CopyAssignment,
-                                            /* ConstRHS */ Const,
-                                            /* Diagnose */ false);
-  }
-
-  setupImplicitSpecialMemberType(CopyAssignment, RetType, ArgType);
-
-  // Add the parameter to the operator.
-  ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment,
-                                               ClassLoc, ClassLoc,
-                                               /*Id=*/nullptr, ArgType,
-                                               /*TInfo=*/nullptr, SC_None,
-                                               nullptr);
-  CopyAssignment->setParams(FromParam);
-
-  CopyAssignment->setTrivial(
-    ClassDecl->needsOverloadResolutionForCopyAssignment()
-      ? SpecialMemberIsTrivial(CopyAssignment, CXXCopyAssignment)
-      : ClassDecl->hasTrivialCopyAssignment());
-
-  // Note that we have added this copy-assignment operator.
-  ++ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, CopyAssignment);
-
-  if (ShouldDeleteSpecialMember(CopyAssignment, CXXCopyAssignment))
-    SetDeclDeleted(CopyAssignment, ClassLoc);
-
-  if (S)
-    PushOnScopeChains(CopyAssignment, S, false);
-  ClassDecl->addDecl(CopyAssignment);
-
-  return CopyAssignment;
-}
-
-/// Diagnose an implicit copy operation for a class which is odr-used, but
-/// which is deprecated because the class has a user-declared copy constructor,
-/// copy assignment operator, or destructor.
-static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp) {
-  assert(CopyOp->isImplicit());
-
-  CXXRecordDecl *RD = CopyOp->getParent();
-  CXXMethodDecl *UserDeclaredOperation = nullptr;
-
-  // In Microsoft mode, assignment operations don't affect constructors and
-  // vice versa.
-  if (RD->hasUserDeclaredDestructor()) {
-    UserDeclaredOperation = RD->getDestructor();
-  } else if (!isa<CXXConstructorDecl>(CopyOp) &&
-             RD->hasUserDeclaredCopyConstructor() &&
-             !S.getLangOpts().MSVCCompat) {
-    // Find any user-declared copy constructor.
-    for (auto *I : RD->ctors()) {
-      if (I->isCopyConstructor()) {
-        UserDeclaredOperation = I;
-        break;
-      }
-    }
-    assert(UserDeclaredOperation);
-  } else if (isa<CXXConstructorDecl>(CopyOp) &&
-             RD->hasUserDeclaredCopyAssignment() &&
-             !S.getLangOpts().MSVCCompat) {
-    // Find any user-declared move assignment operator.
-    for (auto *I : RD->methods()) {
-      if (I->isCopyAssignmentOperator()) {
-        UserDeclaredOperation = I;
-        break;
-      }
-    }
-    assert(UserDeclaredOperation);
-  }
-
-  if (UserDeclaredOperation) {
-    S.Diag(UserDeclaredOperation->getLocation(),
-         diag::warn_deprecated_copy_operation)
-      << RD << /*copy assignment*/!isa<CXXConstructorDecl>(CopyOp)
-      << /*destructor*/isa<CXXDestructorDecl>(UserDeclaredOperation);
-  }
-}
-
-void Sema::DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
-                                        CXXMethodDecl *CopyAssignOperator) {
-  assert((CopyAssignOperator->isDefaulted() &&
-          CopyAssignOperator->isOverloadedOperator() &&
-          CopyAssignOperator->getOverloadedOperator() == OO_Equal &&
-          !CopyAssignOperator->doesThisDeclarationHaveABody() &&
-          !CopyAssignOperator->isDeleted()) &&
-         "DefineImplicitCopyAssignment called for wrong function");
-  if (CopyAssignOperator->willHaveBody() || CopyAssignOperator->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = CopyAssignOperator->getParent();
-  if (ClassDecl->isInvalidDecl()) {
-    CopyAssignOperator->setInvalidDecl();
-    return;
-  }
-
-  SynthesizedFunctionScope Scope(*this, CopyAssignOperator);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       CopyAssignOperator->getType()->castAs<FunctionProtoType>());
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  // C++11 [class.copy]p18:
-  //   The [definition of an implicitly declared copy assignment operator] is
-  //   deprecated if the class has a user-declared copy constructor or a
-  //   user-declared destructor.
-  if (getLangOpts().CPlusPlus11 && CopyAssignOperator->isImplicit())
-    diagnoseDeprecatedCopyOperation(*this, CopyAssignOperator);
-
-  // C++0x [class.copy]p30:
-  //   The implicitly-defined or explicitly-defaulted copy assignment operator
-  //   for a non-union class X performs memberwise copy assignment of its
-  //   subobjects. The direct base classes of X are assigned first, in the
-  //   order of their declaration in the base-specifier-list, and then the
-  //   immediate non-static data members of X are assigned, in the order in
-  //   which they were declared in the class definition.
-
-  // The statements that form the synthesized function body.
-  SmallVector<Stmt*, 8> Statements;
-
-  // The parameter for the "other" object, which we are copying from.
-  ParmVarDecl *Other = CopyAssignOperator->getParamDecl(0);
-  Qualifiers OtherQuals = Other->getType().getQualifiers();
-  QualType OtherRefType = Other->getType();
-  if (const LValueReferenceType *OtherRef
-                                = OtherRefType->getAs<LValueReferenceType>()) {
-    OtherRefType = OtherRef->getPointeeType();
-    OtherQuals = OtherRefType.getQualifiers();
-  }
-
-  // Our location for everything implicitly-generated.
-  SourceLocation Loc = CopyAssignOperator->getEndLoc().isValid()
-                           ? CopyAssignOperator->getEndLoc()
-                           : CopyAssignOperator->getLocation();
-
-  // Builds a DeclRefExpr for the "other" object.
-  RefBuilder OtherRef(Other, OtherRefType);
-
-  // Builds the "this" pointer.
-  ThisBuilder This;
-
-  // Assign base classes.
-  bool Invalid = false;
-  for (auto &Base : ClassDecl->bases()) {
-    // Form the assignment:
-    //   static_cast<Base*>(this)->Base::operator=(static_cast<Base&>(other));
-    QualType BaseType = Base.getType().getUnqualifiedType();
-    if (!BaseType->isRecordType()) {
-      Invalid = true;
-      continue;
-    }
-
-    CXXCastPath BasePath;
-    BasePath.push_back(&Base);
-
-    // Construct the "from" expression, which is an implicit cast to the
-    // appropriately-qualified base type.
-    CastBuilder From(OtherRef, Context.getQualifiedType(BaseType, OtherQuals),
-                     VK_LValue, BasePath);
-
-    // Dereference "this".
-    DerefBuilder DerefThis(This);
-    CastBuilder To(DerefThis,
-                   Context.getQualifiedType(
-                       BaseType, CopyAssignOperator->getTypeQualifiers()),
-                   VK_LValue, BasePath);
-
-    // Build the copy.
-    StmtResult Copy = buildSingleCopyAssign(*this, Loc, BaseType,
-                                            To, From,
-                                            /*CopyingBaseSubobject=*/true,
-                                            /*Copying=*/true);
-    if (Copy.isInvalid()) {
-      CopyAssignOperator->setInvalidDecl();
-      return;
-    }
-
-    // Success! Record the copy.
-    Statements.push_back(Copy.getAs<Expr>());
-  }
-
-  // Assign non-static members.
-  for (auto *Field : ClassDecl->fields()) {
-    // FIXME: We should form some kind of AST representation for the implied
-    // memcpy in a union copy operation.
-    if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
-      continue;
-
-    if (Field->isInvalidDecl()) {
-      Invalid = true;
-      continue;
-    }
-
-    // Check for members of reference type; we can't copy those.
-    if (Field->getType()->isReferenceType()) {
-      Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
-        << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
-      Diag(Field->getLocation(), diag::note_declared_at);
-      Invalid = true;
-      continue;
-    }
-
-    // Check for members of const-qualified, non-class type.
-    QualType BaseType = Context.getBaseElementType(Field->getType());
-    if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
-      Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
-        << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
-      Diag(Field->getLocation(), diag::note_declared_at);
-      Invalid = true;
-      continue;
-    }
-
-    // Suppress assigning zero-width bitfields.
-    if (Field->isZeroLengthBitField(Context))
-      continue;
-
-    QualType FieldType = Field->getType().getNonReferenceType();
-    if (FieldType->isIncompleteArrayType()) {
-      assert(ClassDecl->hasFlexibleArrayMember() &&
-             "Incomplete array type is not valid");
-      continue;
-    }
-
-    // Build references to the field in the object we're copying from and to.
-    CXXScopeSpec SS; // Intentionally empty
-    LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
-                              LookupMemberName);
-    MemberLookup.addDecl(Field);
-    MemberLookup.resolveKind();
-
-    MemberBuilder From(OtherRef, OtherRefType, /*IsArrow=*/false, MemberLookup);
-
-    MemberBuilder To(This, getCurrentThisType(), /*IsArrow=*/true, MemberLookup);
-
-    // Build the copy of this field.
-    StmtResult Copy = buildSingleCopyAssign(*this, Loc, FieldType,
-                                            To, From,
-                                            /*CopyingBaseSubobject=*/false,
-                                            /*Copying=*/true);
-    if (Copy.isInvalid()) {
-      CopyAssignOperator->setInvalidDecl();
-      return;
-    }
-
-    // Success! Record the copy.
-    Statements.push_back(Copy.getAs<Stmt>());
-  }
-
-  if (!Invalid) {
-    // Add a "return *this;"
-    ExprResult ThisObj = CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
-
-    StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
-    if (Return.isInvalid())
-      Invalid = true;
-    else
-      Statements.push_back(Return.getAs<Stmt>());
-  }
-
-  if (Invalid) {
-    CopyAssignOperator->setInvalidDecl();
-    return;
-  }
-
-  StmtResult Body;
-  {
-    CompoundScopeRAII CompoundScope(*this);
-    Body = ActOnCompoundStmt(Loc, Loc, Statements,
-                             /*isStmtExpr=*/false);
-    assert(!Body.isInvalid() && "Compound statement creation cannot fail");
-  }
-  CopyAssignOperator->setBody(Body.getAs<Stmt>());
-  CopyAssignOperator->markUsed(Context);
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(CopyAssignOperator);
-  }
-}
-
-CXXMethodDecl *Sema::DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl) {
-  assert(ClassDecl->needsImplicitMoveAssignment());
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveAssignment);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  // Note: The following rules are largely analoguous to the move
-  // constructor rules.
-
-  QualType ArgType = Context.getTypeDeclType(ClassDecl);
-  QualType RetType = Context.getLValueReferenceType(ArgType);
-  ArgType = Context.getRValueReferenceType(ArgType);
-
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
-                                                     CXXMoveAssignment,
-                                                     false);
-
-  //   An implicitly-declared move assignment operator is an inline public
-  //   member of its class.
-  DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-  CXXMethodDecl *MoveAssignment =
-      CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
-                            /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
-                            /*isInline=*/true, Constexpr, SourceLocation());
-  MoveAssignment->setAccess(AS_public);
-  MoveAssignment->setDefaulted();
-  MoveAssignment->setImplicit();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveAssignment,
-                                            MoveAssignment,
-                                            /* ConstRHS */ false,
-                                            /* Diagnose */ false);
-  }
-
-  // Build an exception specification pointing back at this member.
-  FunctionProtoType::ExtProtoInfo EPI =
-      getImplicitMethodEPI(*this, MoveAssignment);
-  MoveAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
-
-  // Add the parameter to the operator.
-  ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveAssignment,
-                                               ClassLoc, ClassLoc,
-                                               /*Id=*/nullptr, ArgType,
-                                               /*TInfo=*/nullptr, SC_None,
-                                               nullptr);
-  MoveAssignment->setParams(FromParam);
-
-  MoveAssignment->setTrivial(
-    ClassDecl->needsOverloadResolutionForMoveAssignment()
-      ? SpecialMemberIsTrivial(MoveAssignment, CXXMoveAssignment)
-      : ClassDecl->hasTrivialMoveAssignment());
-
-  // Note that we have added this copy-assignment operator.
-  ++ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, MoveAssignment);
-
-  if (ShouldDeleteSpecialMember(MoveAssignment, CXXMoveAssignment)) {
-    ClassDecl->setImplicitMoveAssignmentIsDeleted();
-    SetDeclDeleted(MoveAssignment, ClassLoc);
-  }
-
-  if (S)
-    PushOnScopeChains(MoveAssignment, S, false);
-  ClassDecl->addDecl(MoveAssignment);
-
-  return MoveAssignment;
-}
-
-/// Check if we're implicitly defining a move assignment operator for a class
-/// with virtual bases. Such a move assignment might move-assign the virtual
-/// base multiple times.
-static void checkMoveAssignmentForRepeatedMove(Sema &S, CXXRecordDecl *Class,
-                                               SourceLocation CurrentLocation) {
-  assert(!Class->isDependentContext() && "should not define dependent move");
-
-  // Only a virtual base could get implicitly move-assigned multiple times.
-  // Only a non-trivial move assignment can observe this. We only want to
-  // diagnose if we implicitly define an assignment operator that assigns
-  // two base classes, both of which move-assign the same virtual base.
-  if (Class->getNumVBases() == 0 || Class->hasTrivialMoveAssignment() ||
-      Class->getNumBases() < 2)
-    return;
-
-  llvm::SmallVector<CXXBaseSpecifier *, 16> Worklist;
-  typedef llvm::DenseMap<CXXRecordDecl*, CXXBaseSpecifier*> VBaseMap;
-  VBaseMap VBases;
-
-  for (auto &BI : Class->bases()) {
-    Worklist.push_back(&BI);
-    while (!Worklist.empty()) {
-      CXXBaseSpecifier *BaseSpec = Worklist.pop_back_val();
-      CXXRecordDecl *Base = BaseSpec->getType()->getAsCXXRecordDecl();
-
-      // If the base has no non-trivial move assignment operators,
-      // we don't care about moves from it.
-      if (!Base->hasNonTrivialMoveAssignment())
-        continue;
-
-      // If there's nothing virtual here, skip it.
-      if (!BaseSpec->isVirtual() && !Base->getNumVBases())
-        continue;
-
-      // If we're not actually going to call a move assignment for this base,
-      // or the selected move assignment is trivial, skip it.
-      Sema::SpecialMemberOverloadResult SMOR =
-        S.LookupSpecialMember(Base, Sema::CXXMoveAssignment,
-                              /*ConstArg*/false, /*VolatileArg*/false,
-                              /*RValueThis*/true, /*ConstThis*/false,
-                              /*VolatileThis*/false);
-      if (!SMOR.getMethod() || SMOR.getMethod()->isTrivial() ||
-          !SMOR.getMethod()->isMoveAssignmentOperator())
-        continue;
-
-      if (BaseSpec->isVirtual()) {
-        // We're going to move-assign this virtual base, and its move
-        // assignment operator is not trivial. If this can happen for
-        // multiple distinct direct bases of Class, diagnose it. (If it
-        // only happens in one base, we'll diagnose it when synthesizing
-        // that base class's move assignment operator.)
-        CXXBaseSpecifier *&Existing =
-            VBases.insert(std::make_pair(Base->getCanonicalDecl(), &BI))
-                .first->second;
-        if (Existing && Existing != &BI) {
-          S.Diag(CurrentLocation, diag::warn_vbase_moved_multiple_times)
-            << Class << Base;
-          S.Diag(Existing->getBeginLoc(), diag::note_vbase_moved_here)
-              << (Base->getCanonicalDecl() ==
-                  Existing->getType()->getAsCXXRecordDecl()->getCanonicalDecl())
-              << Base << Existing->getType() << Existing->getSourceRange();
-          S.Diag(BI.getBeginLoc(), diag::note_vbase_moved_here)
-              << (Base->getCanonicalDecl() ==
-                  BI.getType()->getAsCXXRecordDecl()->getCanonicalDecl())
-              << Base << BI.getType() << BaseSpec->getSourceRange();
-
-          // Only diagnose each vbase once.
-          Existing = nullptr;
-        }
-      } else {
-        // Only walk over bases that have defaulted move assignment operators.
-        // We assume that any user-provided move assignment operator handles
-        // the multiple-moves-of-vbase case itself somehow.
-        if (!SMOR.getMethod()->isDefaulted())
-          continue;
-
-        // We're going to move the base classes of Base. Add them to the list.
-        for (auto &BI : Base->bases())
-          Worklist.push_back(&BI);
-      }
-    }
-  }
-}
-
-void Sema::DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
-                                        CXXMethodDecl *MoveAssignOperator) {
-  assert((MoveAssignOperator->isDefaulted() &&
-          MoveAssignOperator->isOverloadedOperator() &&
-          MoveAssignOperator->getOverloadedOperator() == OO_Equal &&
-          !MoveAssignOperator->doesThisDeclarationHaveABody() &&
-          !MoveAssignOperator->isDeleted()) &&
-         "DefineImplicitMoveAssignment called for wrong function");
-  if (MoveAssignOperator->willHaveBody() || MoveAssignOperator->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = MoveAssignOperator->getParent();
-  if (ClassDecl->isInvalidDecl()) {
-    MoveAssignOperator->setInvalidDecl();
-    return;
-  }
-
-  // C++0x [class.copy]p28:
-  //   The implicitly-defined or move assignment operator for a non-union class
-  //   X performs memberwise move assignment of its subobjects. The direct base
-  //   classes of X are assigned first, in the order of their declaration in the
-  //   base-specifier-list, and then the immediate non-static data members of X
-  //   are assigned, in the order in which they were declared in the class
-  //   definition.
-
-  // Issue a warning if our implicit move assignment operator will move
-  // from a virtual base more than once.
-  checkMoveAssignmentForRepeatedMove(*this, ClassDecl, CurrentLocation);
-
-  SynthesizedFunctionScope Scope(*this, MoveAssignOperator);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       MoveAssignOperator->getType()->castAs<FunctionProtoType>());
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  // The statements that form the synthesized function body.
-  SmallVector<Stmt*, 8> Statements;
-
-  // The parameter for the "other" object, which we are move from.
-  ParmVarDecl *Other = MoveAssignOperator->getParamDecl(0);
-  QualType OtherRefType = Other->getType()->
-      getAs<RValueReferenceType>()->getPointeeType();
-
-  // Our location for everything implicitly-generated.
-  SourceLocation Loc = MoveAssignOperator->getEndLoc().isValid()
-                           ? MoveAssignOperator->getEndLoc()
-                           : MoveAssignOperator->getLocation();
-
-  // Builds a reference to the "other" object.
-  RefBuilder OtherRef(Other, OtherRefType);
-  // Cast to rvalue.
-  MoveCastBuilder MoveOther(OtherRef);
-
-  // Builds the "this" pointer.
-  ThisBuilder This;
-
-  // Assign base classes.
-  bool Invalid = false;
-  for (auto &Base : ClassDecl->bases()) {
-    // C++11 [class.copy]p28:
-    //   It is unspecified whether subobjects representing virtual base classes
-    //   are assigned more than once by the implicitly-defined copy assignment
-    //   operator.
-    // FIXME: Do not assign to a vbase that will be assigned by some other base
-    // class. For a move-assignment, this can result in the vbase being moved
-    // multiple times.
-
-    // Form the assignment:
-    //   static_cast<Base*>(this)->Base::operator=(static_cast<Base&&>(other));
-    QualType BaseType = Base.getType().getUnqualifiedType();
-    if (!BaseType->isRecordType()) {
-      Invalid = true;
-      continue;
-    }
-
-    CXXCastPath BasePath;
-    BasePath.push_back(&Base);
-
-    // Construct the "from" expression, which is an implicit cast to the
-    // appropriately-qualified base type.
-    CastBuilder From(OtherRef, BaseType, VK_XValue, BasePath);
-
-    // Dereference "this".
-    DerefBuilder DerefThis(This);
-
-    // Implicitly cast "this" to the appropriately-qualified base type.
-    CastBuilder To(DerefThis,
-                   Context.getQualifiedType(
-                       BaseType, MoveAssignOperator->getTypeQualifiers()),
-                   VK_LValue, BasePath);
-
-    // Build the move.
-    StmtResult Move = buildSingleCopyAssign(*this, Loc, BaseType,
-                                            To, From,
-                                            /*CopyingBaseSubobject=*/true,
-                                            /*Copying=*/false);
-    if (Move.isInvalid()) {
-      MoveAssignOperator->setInvalidDecl();
-      return;
-    }
-
-    // Success! Record the move.
-    Statements.push_back(Move.getAs<Expr>());
-  }
-
-  // Assign non-static members.
-  for (auto *Field : ClassDecl->fields()) {
-    // FIXME: We should form some kind of AST representation for the implied
-    // memcpy in a union copy operation.
-    if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
-      continue;
-
-    if (Field->isInvalidDecl()) {
-      Invalid = true;
-      continue;
-    }
-
-    // Check for members of reference type; we can't move those.
-    if (Field->getType()->isReferenceType()) {
-      Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
-        << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
-      Diag(Field->getLocation(), diag::note_declared_at);
-      Invalid = true;
-      continue;
-    }
-
-    // Check for members of const-qualified, non-class type.
-    QualType BaseType = Context.getBaseElementType(Field->getType());
-    if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
-      Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
-        << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
-      Diag(Field->getLocation(), diag::note_declared_at);
-      Invalid = true;
-      continue;
-    }
-
-    // Suppress assigning zero-width bitfields.
-    if (Field->isZeroLengthBitField(Context))
-      continue;
-
-    QualType FieldType = Field->getType().getNonReferenceType();
-    if (FieldType->isIncompleteArrayType()) {
-      assert(ClassDecl->hasFlexibleArrayMember() &&
-             "Incomplete array type is not valid");
-      continue;
-    }
-
-    // Build references to the field in the object we're copying from and to.
-    LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
-                              LookupMemberName);
-    MemberLookup.addDecl(Field);
-    MemberLookup.resolveKind();
-    MemberBuilder From(MoveOther, OtherRefType,
-                       /*IsArrow=*/false, MemberLookup);
-    MemberBuilder To(This, getCurrentThisType(),
-                     /*IsArrow=*/true, MemberLookup);
-
-    assert(!From.build(*this, Loc)->isLValue() && // could be xvalue or prvalue
-        "Member reference with rvalue base must be rvalue except for reference "
-        "members, which aren't allowed for move assignment.");
-
-    // Build the move of this field.
-    StmtResult Move = buildSingleCopyAssign(*this, Loc, FieldType,
-                                            To, From,
-                                            /*CopyingBaseSubobject=*/false,
-                                            /*Copying=*/false);
-    if (Move.isInvalid()) {
-      MoveAssignOperator->setInvalidDecl();
-      return;
-    }
-
-    // Success! Record the copy.
-    Statements.push_back(Move.getAs<Stmt>());
-  }
-
-  if (!Invalid) {
-    // Add a "return *this;"
-    ExprResult ThisObj =
-        CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
-
-    StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
-    if (Return.isInvalid())
-      Invalid = true;
-    else
-      Statements.push_back(Return.getAs<Stmt>());
-  }
-
-  if (Invalid) {
-    MoveAssignOperator->setInvalidDecl();
-    return;
-  }
-
-  StmtResult Body;
-  {
-    CompoundScopeRAII CompoundScope(*this);
-    Body = ActOnCompoundStmt(Loc, Loc, Statements,
-                             /*isStmtExpr=*/false);
-    assert(!Body.isInvalid() && "Compound statement creation cannot fail");
-  }
-  MoveAssignOperator->setBody(Body.getAs<Stmt>());
-  MoveAssignOperator->markUsed(Context);
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(MoveAssignOperator);
-  }
-}
-
-CXXConstructorDecl *Sema::DeclareImplicitCopyConstructor(
-                                                    CXXRecordDecl *ClassDecl) {
-  // C++ [class.copy]p4:
-  //   If the class definition does not explicitly declare a copy
-  //   constructor, one is declared implicitly.
-  assert(ClassDecl->needsImplicitCopyConstructor());
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyConstructor);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  QualType ClassType = Context.getTypeDeclType(ClassDecl);
-  QualType ArgType = ClassType;
-  bool Const = ClassDecl->implicitCopyConstructorHasConstParam();
-  if (Const)
-    ArgType = ArgType.withConst();
-
-  if (Context.getLangOpts().OpenCLCPlusPlus)
-    ArgType = Context.getAddrSpaceQualType(ArgType, LangAS::opencl_generic);
-
-  ArgType = Context.getLValueReferenceType(ArgType);
-
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
-                                                     CXXCopyConstructor,
-                                                     Const);
-
-  DeclarationName Name
-    = Context.DeclarationNames.getCXXConstructorName(
-                                           Context.getCanonicalType(ClassType));
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-
-  //   An implicitly-declared copy constructor is an inline public
-  //   member of its class.
-  CXXConstructorDecl *CopyConstructor = CXXConstructorDecl::Create(
-      Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
-      /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
-      Constexpr);
-  CopyConstructor->setAccess(AS_public);
-  CopyConstructor->setDefaulted();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyConstructor,
-                                            CopyConstructor,
-                                            /* ConstRHS */ Const,
-                                            /* Diagnose */ false);
-  }
-
-  setupImplicitSpecialMemberType(CopyConstructor, Context.VoidTy, ArgType);
-
-  // Add the parameter to the constructor.
-  ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor,
-                                               ClassLoc, ClassLoc,
-                                               /*IdentifierInfo=*/nullptr,
-                                               ArgType, /*TInfo=*/nullptr,
-                                               SC_None, nullptr);
-  CopyConstructor->setParams(FromParam);
-
-  CopyConstructor->setTrivial(
-      ClassDecl->needsOverloadResolutionForCopyConstructor()
-          ? SpecialMemberIsTrivial(CopyConstructor, CXXCopyConstructor)
-          : ClassDecl->hasTrivialCopyConstructor());
-
-  CopyConstructor->setTrivialForCall(
-      ClassDecl->hasAttr<TrivialABIAttr>() ||
-      (ClassDecl->needsOverloadResolutionForCopyConstructor()
-           ? SpecialMemberIsTrivial(CopyConstructor, CXXCopyConstructor,
-             TAH_ConsiderTrivialABI)
-           : ClassDecl->hasTrivialCopyConstructorForCall()));
-
-  // Note that we have declared this constructor.
-  ++ASTContext::NumImplicitCopyConstructorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, CopyConstructor);
-
-  if (ShouldDeleteSpecialMember(CopyConstructor, CXXCopyConstructor)) {
-    ClassDecl->setImplicitCopyConstructorIsDeleted();
-    SetDeclDeleted(CopyConstructor, ClassLoc);
-  }
-
-  if (S)
-    PushOnScopeChains(CopyConstructor, S, false);
-  ClassDecl->addDecl(CopyConstructor);
-
-  return CopyConstructor;
-}
-
-void Sema::DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
-                                         CXXConstructorDecl *CopyConstructor) {
-  assert((CopyConstructor->isDefaulted() &&
-          CopyConstructor->isCopyConstructor() &&
-          !CopyConstructor->doesThisDeclarationHaveABody() &&
-          !CopyConstructor->isDeleted()) &&
-         "DefineImplicitCopyConstructor - call it for implicit copy ctor");
-  if (CopyConstructor->willHaveBody() || CopyConstructor->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = CopyConstructor->getParent();
-  assert(ClassDecl && "DefineImplicitCopyConstructor - invalid constructor");
-
-  SynthesizedFunctionScope Scope(*this, CopyConstructor);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       CopyConstructor->getType()->castAs<FunctionProtoType>());
-  MarkVTableUsed(CurrentLocation, ClassDecl);
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  // C++11 [class.copy]p7:
-  //   The [definition of an implicitly declared copy constructor] is
-  //   deprecated if the class has a user-declared copy assignment operator
-  //   or a user-declared destructor.
-  if (getLangOpts().CPlusPlus11 && CopyConstructor->isImplicit())
-    diagnoseDeprecatedCopyOperation(*this, CopyConstructor);
-
-  if (SetCtorInitializers(CopyConstructor, /*AnyErrors=*/false)) {
-    CopyConstructor->setInvalidDecl();
-  }  else {
-    SourceLocation Loc = CopyConstructor->getEndLoc().isValid()
-                             ? CopyConstructor->getEndLoc()
-                             : CopyConstructor->getLocation();
-    Sema::CompoundScopeRAII CompoundScope(*this);
-    CopyConstructor->setBody(
-        ActOnCompoundStmt(Loc, Loc, None, /*isStmtExpr=*/false).getAs<Stmt>());
-    CopyConstructor->markUsed(Context);
-  }
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(CopyConstructor);
-  }
-}
-
-CXXConstructorDecl *Sema::DeclareImplicitMoveConstructor(
-                                                    CXXRecordDecl *ClassDecl) {
-  assert(ClassDecl->needsImplicitMoveConstructor());
-
-  DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveConstructor);
-  if (DSM.isAlreadyBeingDeclared())
-    return nullptr;
-
-  QualType ClassType = Context.getTypeDeclType(ClassDecl);
-
-  QualType ArgType = ClassType;
-  if (Context.getLangOpts().OpenCLCPlusPlus)
-    ArgType = Context.getAddrSpaceQualType(ClassType, LangAS::opencl_generic);
-  ArgType = Context.getRValueReferenceType(ArgType);
-
-  bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
-                                                     CXXMoveConstructor,
-                                                     false);
-
-  DeclarationName Name
-    = Context.DeclarationNames.getCXXConstructorName(
-                                           Context.getCanonicalType(ClassType));
-  SourceLocation ClassLoc = ClassDecl->getLocation();
-  DeclarationNameInfo NameInfo(Name, ClassLoc);
-
-  // C++11 [class.copy]p11:
-  //   An implicitly-declared copy/move constructor is an inline public
-  //   member of its class.
-  CXXConstructorDecl *MoveConstructor = CXXConstructorDecl::Create(
-      Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
-      /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
-      Constexpr);
-  MoveConstructor->setAccess(AS_public);
-  MoveConstructor->setDefaulted();
-
-  if (getLangOpts().CUDA) {
-    inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveConstructor,
-                                            MoveConstructor,
-                                            /* ConstRHS */ false,
-                                            /* Diagnose */ false);
-  }
-
-  setupImplicitSpecialMemberType(MoveConstructor, Context.VoidTy, ArgType);
-
-  // Add the parameter to the constructor.
-  ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveConstructor,
-                                               ClassLoc, ClassLoc,
-                                               /*IdentifierInfo=*/nullptr,
-                                               ArgType, /*TInfo=*/nullptr,
-                                               SC_None, nullptr);
-  MoveConstructor->setParams(FromParam);
-
-  MoveConstructor->setTrivial(
-      ClassDecl->needsOverloadResolutionForMoveConstructor()
-          ? SpecialMemberIsTrivial(MoveConstructor, CXXMoveConstructor)
-          : ClassDecl->hasTrivialMoveConstructor());
-
-  MoveConstructor->setTrivialForCall(
-      ClassDecl->hasAttr<TrivialABIAttr>() ||
-      (ClassDecl->needsOverloadResolutionForMoveConstructor()
-           ? SpecialMemberIsTrivial(MoveConstructor, CXXMoveConstructor,
-                                    TAH_ConsiderTrivialABI)
-           : ClassDecl->hasTrivialMoveConstructorForCall()));
-
-  // Note that we have declared this constructor.
-  ++ASTContext::NumImplicitMoveConstructorsDeclared;
-
-  Scope *S = getScopeForContext(ClassDecl);
-  CheckImplicitSpecialMemberDeclaration(S, MoveConstructor);
-
-  if (ShouldDeleteSpecialMember(MoveConstructor, CXXMoveConstructor)) {
-    ClassDecl->setImplicitMoveConstructorIsDeleted();
-    SetDeclDeleted(MoveConstructor, ClassLoc);
-  }
-
-  if (S)
-    PushOnScopeChains(MoveConstructor, S, false);
-  ClassDecl->addDecl(MoveConstructor);
-
-  return MoveConstructor;
-}
-
-void Sema::DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
-                                         CXXConstructorDecl *MoveConstructor) {
-  assert((MoveConstructor->isDefaulted() &&
-          MoveConstructor->isMoveConstructor() &&
-          !MoveConstructor->doesThisDeclarationHaveABody() &&
-          !MoveConstructor->isDeleted()) &&
-         "DefineImplicitMoveConstructor - call it for implicit move ctor");
-  if (MoveConstructor->willHaveBody() || MoveConstructor->isInvalidDecl())
-    return;
-
-  CXXRecordDecl *ClassDecl = MoveConstructor->getParent();
-  assert(ClassDecl && "DefineImplicitMoveConstructor - invalid constructor");
-
-  SynthesizedFunctionScope Scope(*this, MoveConstructor);
-
-  // The exception specification is needed because we are defining the
-  // function.
-  ResolveExceptionSpec(CurrentLocation,
-                       MoveConstructor->getType()->castAs<FunctionProtoType>());
-  MarkVTableUsed(CurrentLocation, ClassDecl);
-
-  // Add a context note for diagnostics produced after this point.
-  Scope.addContextNote(CurrentLocation);
-
-  if (SetCtorInitializers(MoveConstructor, /*AnyErrors=*/false)) {
-    MoveConstructor->setInvalidDecl();
-  } else {
-    SourceLocation Loc = MoveConstructor->getEndLoc().isValid()
-                             ? MoveConstructor->getEndLoc()
-                             : MoveConstructor->getLocation();
-    Sema::CompoundScopeRAII CompoundScope(*this);
-    MoveConstructor->setBody(ActOnCompoundStmt(
-        Loc, Loc, None, /*isStmtExpr=*/ false).getAs<Stmt>());
-    MoveConstructor->markUsed(Context);
-  }
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(MoveConstructor);
-  }
-}
-
-bool Sema::isImplicitlyDeleted(FunctionDecl *FD) {
-  return FD->isDeleted() && FD->isDefaulted() && isa<CXXMethodDecl>(FD);
-}
-
-void Sema::DefineImplicitLambdaToFunctionPointerConversion(
-                            SourceLocation CurrentLocation,
-                            CXXConversionDecl *Conv) {
-  SynthesizedFunctionScope Scope(*this, Conv);
-  assert(!Conv->getReturnType()->isUndeducedType());
-
-  CXXRecordDecl *Lambda = Conv->getParent();
-  FunctionDecl *CallOp = Lambda->getLambdaCallOperator();
-  FunctionDecl *Invoker = Lambda->getLambdaStaticInvoker();
-
-  if (auto *TemplateArgs = Conv->getTemplateSpecializationArgs()) {
-    CallOp = InstantiateFunctionDeclaration(
-        CallOp->getDescribedFunctionTemplate(), TemplateArgs, CurrentLocation);
-    if (!CallOp)
-      return;
-
-    Invoker = InstantiateFunctionDeclaration(
-        Invoker->getDescribedFunctionTemplate(), TemplateArgs, CurrentLocation);
-    if (!Invoker)
-      return;
-  }
-
-  if (CallOp->isInvalidDecl())
-    return;
-
-  // Mark the call operator referenced (and add to pending instantiations
-  // if necessary).
-  // For both the conversion and static-invoker template specializations
-  // we construct their body's in this function, so no need to add them
-  // to the PendingInstantiations.
-  MarkFunctionReferenced(CurrentLocation, CallOp);
-
-  // Fill in the __invoke function with a dummy implementation. IR generation
-  // will fill in the actual details. Update its type in case it contained
-  // an 'auto'.
-  Invoker->markUsed(Context);
-  Invoker->setReferenced();
-  Invoker->setType(Conv->getReturnType()->getPointeeType());
-  Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
-
-  // Construct the body of the conversion function { return __invoke; }.
-  Expr *FunctionRef = BuildDeclRefExpr(Invoker, Invoker->getType(),
-                                       VK_LValue, Conv->getLocation()).get();
-  assert(FunctionRef && "Can't refer to __invoke function?");
-  Stmt *Return = BuildReturnStmt(Conv->getLocation(), FunctionRef).get();
-  Conv->setBody(CompoundStmt::Create(Context, Return, Conv->getLocation(),
-                                     Conv->getLocation()));
-  Conv->markUsed(Context);
-  Conv->setReferenced();
-
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(Conv);
-    L->CompletedImplicitDefinition(Invoker);
-  }
-}
-
-
-
-void Sema::DefineImplicitLambdaToBlockPointerConversion(
-       SourceLocation CurrentLocation,
-       CXXConversionDecl *Conv)
-{
-  assert(!Conv->getParent()->isGenericLambda());
-
-  SynthesizedFunctionScope Scope(*this, Conv);
-
-  // Copy-initialize the lambda object as needed to capture it.
-  Expr *This = ActOnCXXThis(CurrentLocation).get();
-  Expr *DerefThis =CreateBuiltinUnaryOp(CurrentLocation, UO_Deref, This).get();
-
-  ExprResult BuildBlock = BuildBlockForLambdaConversion(CurrentLocation,
-                                                        Conv->getLocation(),
-                                                        Conv, DerefThis);
-
-  // If we're not under ARC, make sure we still get the _Block_copy/autorelease
-  // behavior.  Note that only the general conversion function does this
-  // (since it's unusable otherwise); in the case where we inline the
-  // block literal, it has block literal lifetime semantics.
-  if (!BuildBlock.isInvalid() && !getLangOpts().ObjCAutoRefCount)
-    BuildBlock = ImplicitCastExpr::Create(Context, BuildBlock.get()->getType(),
-                                          CK_CopyAndAutoreleaseBlockObject,
-                                          BuildBlock.get(), nullptr, VK_RValue);
-
-  if (BuildBlock.isInvalid()) {
-    Diag(CurrentLocation, diag::note_lambda_to_block_conv);
-    Conv->setInvalidDecl();
-    return;
-  }
-
-  // Create the return statement that returns the block from the conversion
-  // function.
-  StmtResult Return = BuildReturnStmt(Conv->getLocation(), BuildBlock.get());
-  if (Return.isInvalid()) {
-    Diag(CurrentLocation, diag::note_lambda_to_block_conv);
-    Conv->setInvalidDecl();
-    return;
-  }
-
-  // Set the body of the conversion function.
-  Stmt *ReturnS = Return.get();
-  Conv->setBody(CompoundStmt::Create(Context, ReturnS, Conv->getLocation(),
-                                     Conv->getLocation()));
-  Conv->markUsed(Context);
-
-  // We're done; notify the mutation listener, if any.
-  if (ASTMutationListener *L = getASTMutationListener()) {
-    L->CompletedImplicitDefinition(Conv);
-  }
-}
-
-/// Determine whether the given list arguments contains exactly one
-/// "real" (non-default) argument.
-static bool hasOneRealArgument(MultiExprArg Args) {
-  switch (Args.size()) {
-  case 0:
-    return false;
-
-  default:
-    if (!Args[1]->isDefaultArgument())
-      return false;
-
-    LLVM_FALLTHROUGH;
-  case 1:
-    return !Args[0]->isDefaultArgument();
-  }
-
-  return false;
-}
-
-ExprResult
-Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
-                            NamedDecl *FoundDecl,
-                            CXXConstructorDecl *Constructor,
-                            MultiExprArg ExprArgs,
-                            bool HadMultipleCandidates,
-                            bool IsListInitialization,
-                            bool IsStdInitListInitialization,
-                            bool RequiresZeroInit,
-                            unsigned ConstructKind,
-                            SourceRange ParenRange) {
-  bool Elidable = false;
-
-  // C++0x [class.copy]p34:
-  //   When certain criteria are met, an implementation is allowed to
-  //   omit the copy/move construction of a class object, even if the
-  //   copy/move constructor and/or destructor for the object have
-  //   side effects. [...]
-  //     - when a temporary class object that has not been bound to a
-  //       reference (12.2) would be copied/moved to a class object
-  //       with the same cv-unqualified type, the copy/move operation
-  //       can be omitted by constructing the temporary object
-  //       directly into the target of the omitted copy/move
-  if (ConstructKind == CXXConstructExpr::CK_Complete && Constructor &&
-      Constructor->isCopyOrMoveConstructor() && hasOneRealArgument(ExprArgs)) {
-    Expr *SubExpr = ExprArgs[0];
-    Elidable = SubExpr->isTemporaryObject(
-        Context, cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
-  }
-
-  return BuildCXXConstructExpr(ConstructLoc, DeclInitType,
-                               FoundDecl, Constructor,
-                               Elidable, ExprArgs, HadMultipleCandidates,
-                               IsListInitialization,
-                               IsStdInitListInitialization, RequiresZeroInit,
-                               ConstructKind, ParenRange);
-}
-
-ExprResult
-Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
-                            NamedDecl *FoundDecl,
-                            CXXConstructorDecl *Constructor,
-                            bool Elidable,
-                            MultiExprArg ExprArgs,
-                            bool HadMultipleCandidates,
-                            bool IsListInitialization,
-                            bool IsStdInitListInitialization,
-                            bool RequiresZeroInit,
-                            unsigned ConstructKind,
-                            SourceRange ParenRange) {
-  if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(FoundDecl)) {
-    Constructor = findInheritingConstructor(ConstructLoc, Constructor, Shadow);
-    if (DiagnoseUseOfDecl(Constructor, ConstructLoc))
-      return ExprError();
-  }
-
-  return BuildCXXConstructExpr(
-      ConstructLoc, DeclInitType, Constructor, Elidable, ExprArgs,
-      HadMultipleCandidates, IsListInitialization, IsStdInitListInitialization,
-      RequiresZeroInit, ConstructKind, ParenRange);
-}
-
-/// BuildCXXConstructExpr - Creates a complete call to a constructor,
-/// including handling of its default argument expressions.
-ExprResult
-Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
-                            CXXConstructorDecl *Constructor,
-                            bool Elidable,
-                            MultiExprArg ExprArgs,
-                            bool HadMultipleCandidates,
-                            bool IsListInitialization,
-                            bool IsStdInitListInitialization,
-                            bool RequiresZeroInit,
-                            unsigned ConstructKind,
-                            SourceRange ParenRange) {
-  assert(declaresSameEntity(
-             Constructor->getParent(),
-             DeclInitType->getBaseElementTypeUnsafe()->getAsCXXRecordDecl()) &&
-         "given constructor for wrong type");
-  MarkFunctionReferenced(ConstructLoc, Constructor);
-  if (getLangOpts().CUDA && !CheckCUDACall(ConstructLoc, Constructor))
-    return ExprError();
-
-  return CXXConstructExpr::Create(
-      Context, DeclInitType, ConstructLoc, Constructor, Elidable,
-      ExprArgs, HadMultipleCandidates, IsListInitialization,
-      IsStdInitListInitialization, RequiresZeroInit,
-      static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
-      ParenRange);
-}
-
-ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
-  assert(Field->hasInClassInitializer());
-
-  // If we already have the in-class initializer nothing needs to be done.
-  if (Field->getInClassInitializer())
-    return CXXDefaultInitExpr::Create(Context, Loc, Field);
-
-  // If we might have already tried and failed to instantiate, don't try again.
-  if (Field->isInvalidDecl())
-    return ExprError();
-
-  // Maybe we haven't instantiated the in-class initializer. Go check the
-  // pattern FieldDecl to see if it has one.
-  CXXRecordDecl *ParentRD = cast<CXXRecordDecl>(Field->getParent());
-
-  if (isTemplateInstantiation(ParentRD->getTemplateSpecializationKind())) {
-    CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
-    DeclContext::lookup_result Lookup =
-        ClassPattern->lookup(Field->getDeclName());
-
-    // Lookup can return at most two results: the pattern for the field, or the
-    // injected class name of the parent record. No other member can have the
-    // same name as the field.
-    // In modules mode, lookup can return multiple results (coming from
-    // different modules).
-    assert((getLangOpts().Modules || (!Lookup.empty() && Lookup.size() <= 2)) &&
-           "more than two lookup results for field name");
-    FieldDecl *Pattern = dyn_cast<FieldDecl>(Lookup[0]);
-    if (!Pattern) {
-      assert(isa<CXXRecordDecl>(Lookup[0]) &&
-             "cannot have other non-field member with same name");
-      for (auto L : Lookup)
-        if (isa<FieldDecl>(L)) {
-          Pattern = cast<FieldDecl>(L);
-          break;
-        }
-      assert(Pattern && "We must have set the Pattern!");
-    }
-
-    if (!Pattern->hasInClassInitializer() ||
-        InstantiateInClassInitializer(Loc, Field, Pattern,
-                                      getTemplateInstantiationArgs(Field))) {
-      // Don't diagnose this again.
-      Field->setInvalidDecl();
-      return ExprError();
-    }
-    return CXXDefaultInitExpr::Create(Context, Loc, Field);
-  }
-
-  // DR1351:
-  //   If the brace-or-equal-initializer of a non-static data member
-  //   invokes a defaulted default constructor of its class or of an
-  //   enclosing class in a potentially evaluated subexpression, the
-  //   program is ill-formed.
-  //
-  // This resolution is unworkable: the exception specification of the
-  // default constructor can be needed in an unevaluated context, in
-  // particular, in the operand of a noexcept-expression, and we can be
-  // unable to compute an exception specification for an enclosed class.
-  //
-  // Any attempt to resolve the exception specification of a defaulted default
-  // constructor before the initializer is lexically complete will ultimately
-  // come here at which point we can diagnose it.
-  RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
-  Diag(Loc, diag::err_in_class_initializer_not_yet_parsed)
-      << OutermostClass << Field;
-  Diag(Field->getEndLoc(), diag::note_in_class_initializer_not_yet_parsed);
-  // Recover by marking the field invalid, unless we're in a SFINAE context.
-  if (!isSFINAEContext())
-    Field->setInvalidDecl();
-  return ExprError();
-}
-
-void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
-  if (VD->isInvalidDecl()) return;
-
-  CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Record->getDecl());
-  if (ClassDecl->isInvalidDecl()) return;
-  if (ClassDecl->hasIrrelevantDestructor()) return;
-  if (ClassDecl->isDependentContext()) return;
-
-  if (VD->isNoDestroy(getASTContext()))
-    return;
-
-  CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
-  MarkFunctionReferenced(VD->getLocation(), Destructor);
-  CheckDestructorAccess(VD->getLocation(), Destructor,
-                        PDiag(diag::err_access_dtor_var)
-                        << VD->getDeclName()
-                        << VD->getType());
-  DiagnoseUseOfDecl(Destructor, VD->getLocation());
-
-  if (Destructor->isTrivial()) return;
-  if (!VD->hasGlobalStorage()) return;
-
-  // Emit warning for non-trivial dtor in global scope (a real global,
-  // class-static, function-static).
-  Diag(VD->getLocation(), diag::warn_exit_time_destructor);
-
-  // TODO: this should be re-enabled for static locals by !CXAAtExit
-  if (!VD->isStaticLocal())
-    Diag(VD->getLocation(), diag::warn_global_destructor);
-}
-
-/// Given a constructor and the set of arguments provided for the
-/// constructor, convert the arguments and add any required default arguments
-/// to form a proper call to this constructor.
-///
-/// \returns true if an error occurred, false otherwise.
-bool
-Sema::CompleteConstructorCall(CXXConstructorDecl *Constructor,
-                              MultiExprArg ArgsPtr,
-                              SourceLocation Loc,
-                              SmallVectorImpl<Expr*> &ConvertedArgs,
-                              bool AllowExplicit,
-                              bool IsListInitialization) {
-  // FIXME: This duplicates a lot of code from Sema::ConvertArgumentsForCall.
-  unsigned NumArgs = ArgsPtr.size();
-  Expr **Args = ArgsPtr.data();
-
-  const FunctionProtoType *Proto
-    = Constructor->getType()->getAs<FunctionProtoType>();
-  assert(Proto && "Constructor without a prototype?");
-  unsigned NumParams = Proto->getNumParams();
-
-  // If too few arguments are available, we'll fill in the rest with defaults.
-  if (NumArgs < NumParams)
-    ConvertedArgs.reserve(NumParams);
-  else
-    ConvertedArgs.reserve(NumArgs);
-
-  VariadicCallType CallType =
-    Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
-  SmallVector<Expr *, 8> AllArgs;
-  bool Invalid = GatherArgumentsForCall(Loc, Constructor,
-                                        Proto, 0,
-                                        llvm::makeArrayRef(Args, NumArgs),
-                                        AllArgs,
-                                        CallType, AllowExplicit,
-                                        IsListInitialization);
-  ConvertedArgs.append(AllArgs.begin(), AllArgs.end());
-
-  DiagnoseSentinelCalls(Constructor, Loc, AllArgs);
-
-  CheckConstructorCall(Constructor,
-                       llvm::makeArrayRef(AllArgs.data(), AllArgs.size()),
-                       Proto, Loc);
-
-  return Invalid;
-}
-
-static inline bool
-CheckOperatorNewDeleteDeclarationScope(Sema &SemaRef,
-                                       const FunctionDecl *FnDecl) {
-  const DeclContext *DC = FnDecl->getDeclContext()->getRedeclContext();
-  if (isa<NamespaceDecl>(DC)) {
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_delete_declared_in_namespace)
-      << FnDecl->getDeclName();
-  }
-
-  if (isa<TranslationUnitDecl>(DC) &&
-      FnDecl->getStorageClass() == SC_Static) {
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_delete_declared_static)
-      << FnDecl->getDeclName();
-  }
-
-  return false;
-}
-
-static QualType
-RemoveAddressSpaceFromPtr(Sema &SemaRef, const PointerType *PtrTy) {
-  QualType QTy = PtrTy->getPointeeType();
-  QTy = SemaRef.Context.removeAddrSpaceQualType(QTy);
-  return SemaRef.Context.getPointerType(QTy);
-}
-
-static inline bool
-CheckOperatorNewDeleteTypes(Sema &SemaRef, const FunctionDecl *FnDecl,
-                            CanQualType ExpectedResultType,
-                            CanQualType ExpectedFirstParamType,
-                            unsigned DependentParamTypeDiag,
-                            unsigned InvalidParamTypeDiag) {
-  QualType ResultType =
-      FnDecl->getType()->getAs<FunctionType>()->getReturnType();
-
-  // Check that the result type is not dependent.
-  if (ResultType->isDependentType())
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_delete_dependent_result_type)
-    << FnDecl->getDeclName() << ExpectedResultType;
-
-  // OpenCL C++: the operator is valid on any address space.
-  if (SemaRef.getLangOpts().OpenCLCPlusPlus) {
-    if (auto *PtrTy = ResultType->getAs<PointerType>()) {
-      ResultType = RemoveAddressSpaceFromPtr(SemaRef, PtrTy);
-    }
-  }
-
-  // Check that the result type is what we expect.
-  if (SemaRef.Context.getCanonicalType(ResultType) != ExpectedResultType)
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_delete_invalid_result_type)
-    << FnDecl->getDeclName() << ExpectedResultType;
-
-  // A function template must have at least 2 parameters.
-  if (FnDecl->getDescribedFunctionTemplate() && FnDecl->getNumParams() < 2)
-    return SemaRef.Diag(FnDecl->getLocation(),
-                      diag::err_operator_new_delete_template_too_few_parameters)
-        << FnDecl->getDeclName();
-
-  // The function decl must have at least 1 parameter.
-  if (FnDecl->getNumParams() == 0)
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_delete_too_few_parameters)
-      << FnDecl->getDeclName();
-
-  // Check the first parameter type is not dependent.
-  QualType FirstParamType = FnDecl->getParamDecl(0)->getType();
-  if (FirstParamType->isDependentType())
-    return SemaRef.Diag(FnDecl->getLocation(), DependentParamTypeDiag)
-      << FnDecl->getDeclName() << ExpectedFirstParamType;
-
-  // Check that the first parameter type is what we expect.
-  if (SemaRef.getLangOpts().OpenCLCPlusPlus) {
-    // OpenCL C++: the operator is valid on any address space.
-    if (auto *PtrTy =
-            FnDecl->getParamDecl(0)->getType()->getAs<PointerType>()) {
-      FirstParamType = RemoveAddressSpaceFromPtr(SemaRef, PtrTy);
-    }
-  }
-  if (SemaRef.Context.getCanonicalType(FirstParamType).getUnqualifiedType() !=
-      ExpectedFirstParamType)
-    return SemaRef.Diag(FnDecl->getLocation(), InvalidParamTypeDiag)
-    << FnDecl->getDeclName() << ExpectedFirstParamType;
-
-  return false;
-}
-
-static bool
-CheckOperatorNewDeclaration(Sema &SemaRef, const FunctionDecl *FnDecl) {
-  // C++ [basic.stc.dynamic.allocation]p1:
-  //   A program is ill-formed if an allocation function is declared in a
-  //   namespace scope other than global scope or declared static in global
-  //   scope.
-  if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
-    return true;
-
-  CanQualType SizeTy =
-    SemaRef.Context.getCanonicalType(SemaRef.Context.getSizeType());
-
-  // C++ [basic.stc.dynamic.allocation]p1:
-  //  The return type shall be void*. The first parameter shall have type
-  //  std::size_t.
-  if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidPtrTy,
-                                  SizeTy,
-                                  diag::err_operator_new_dependent_param_type,
-                                  diag::err_operator_new_param_type))
-    return true;
-
-  // C++ [basic.stc.dynamic.allocation]p1:
-  //  The first parameter shall not have an associated default argument.
-  if (FnDecl->getParamDecl(0)->hasDefaultArg())
-    return SemaRef.Diag(FnDecl->getLocation(),
-                        diag::err_operator_new_default_arg)
-      << FnDecl->getDeclName() << FnDecl->getParamDecl(0)->getDefaultArgRange();
-
-  return false;
-}
-
-static bool
-CheckOperatorDeleteDeclaration(Sema &SemaRef, FunctionDecl *FnDecl) {
-  // C++ [basic.stc.dynamic.deallocation]p1:
-  //   A program is ill-formed if deallocation functions are declared in a
-  //   namespace scope other than global scope or declared static in global
-  //   scope.
-  if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
-    return true;
-
-  auto *MD = dyn_cast<CXXMethodDecl>(FnDecl);
-
-  // C++ P0722:
-  //   Within a class C, the first parameter of a destroying operator delete
-  //   shall be of type C *. The first parameter of any other deallocation
-  //   function shall be of type void *.
-  CanQualType ExpectedFirstParamType =
-      MD && MD->isDestroyingOperatorDelete()
-          ? SemaRef.Context.getCanonicalType(SemaRef.Context.getPointerType(
-                SemaRef.Context.getRecordType(MD->getParent())))
-          : SemaRef.Context.VoidPtrTy;
-
-  // C++ [basic.stc.dynamic.deallocation]p2:
-  //   Each deallocation function shall return void
-  if (CheckOperatorNewDeleteTypes(
-          SemaRef, FnDecl, SemaRef.Context.VoidTy, ExpectedFirstParamType,
-          diag::err_operator_delete_dependent_param_type,
-          diag::err_operator_delete_param_type))
-    return true;
-
-  // C++ P0722:
-  //   A destroying operator delete shall be a usual deallocation function.
-  if (MD && !MD->getParent()->isDependentContext() &&
-      MD->isDestroyingOperatorDelete() &&
-      !SemaRef.isUsualDeallocationFunction(MD)) {
-    SemaRef.Diag(MD->getLocation(),
-                 diag::err_destroying_operator_delete_not_usual);
-    return true;
-  }
-
-  return false;
-}
-
-/// CheckOverloadedOperatorDeclaration - Check whether the declaration
-/// of this overloaded operator is well-formed. If so, returns false;
-/// otherwise, emits appropriate diagnostics and returns true.
-bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) {
-  assert(FnDecl && FnDecl->isOverloadedOperator() &&
-         "Expected an overloaded operator declaration");
-
-  OverloadedOperatorKind Op = FnDecl->getOverloadedOperator();
-
-  // C++ [over.oper]p5:
-  //   The allocation and deallocation functions, operator new,
-  //   operator new[], operator delete and operator delete[], are
-  //   described completely in 3.7.3. The attributes and restrictions
-  //   found in the rest of this subclause do not apply to them unless
-  //   explicitly stated in 3.7.3.
-  if (Op == OO_Delete || Op == OO_Array_Delete)
-    return CheckOperatorDeleteDeclaration(*this, FnDecl);
-
-  if (Op == OO_New || Op == OO_Array_New)
-    return CheckOperatorNewDeclaration(*this, FnDecl);
-
-  // C++ [over.oper]p6:
-  //   An operator function shall either be a non-static member
-  //   function or be a non-member function and have at least one
-  //   parameter whose type is a class, a reference to a class, an
-  //   enumeration, or a reference to an enumeration.
-  if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) {
-    if (MethodDecl->isStatic())
-      return Diag(FnDecl->getLocation(),
-                  diag::err_operator_overload_static) << FnDecl->getDeclName();
-  } else {
-    bool ClassOrEnumParam = false;
-    for (auto Param : FnDecl->parameters()) {
-      QualType ParamType = Param->getType().getNonReferenceType();
-      if (ParamType->isDependentType() || ParamType->isRecordType() ||
-          ParamType->isEnumeralType()) {
-        ClassOrEnumParam = true;
-        break;
-      }
-    }
-
-    if (!ClassOrEnumParam)
-      return Diag(FnDecl->getLocation(),
-                  diag::err_operator_overload_needs_class_or_enum)
-        << FnDecl->getDeclName();
-  }
-
-  // C++ [over.oper]p8:
-  //   An operator function cannot have default arguments (8.3.6),
-  //   except where explicitly stated below.
-  //
-  // Only the function-call operator allows default arguments
-  // (C++ [over.call]p1).
-  if (Op != OO_Call) {
-    for (auto Param : FnDecl->parameters()) {
-      if (Param->hasDefaultArg())
-        return Diag(Param->getLocation(),
-                    diag::err_operator_overload_default_arg)
-          << FnDecl->getDeclName() << Param->getDefaultArgRange();
-    }
-  }
-
-  static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = {
-    { false, false, false }
-#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
-    , { Unary, Binary, MemberOnly }
-#include "clang/Basic/OperatorKinds.def"
-  };
-
-  bool CanBeUnaryOperator = OperatorUses[Op][0];
-  bool CanBeBinaryOperator = OperatorUses[Op][1];
-  bool MustBeMemberOperator = OperatorUses[Op][2];
-
-  // C++ [over.oper]p8:
-  //   [...] Operator functions cannot have more or fewer parameters
-  //   than the number required for the corresponding operator, as
-  //   described in the rest of this subclause.
-  unsigned NumParams = FnDecl->getNumParams()
-                     + (isa<CXXMethodDecl>(FnDecl)? 1 : 0);
-  if (Op != OO_Call &&
-      ((NumParams == 1 && !CanBeUnaryOperator) ||
-       (NumParams == 2 && !CanBeBinaryOperator) ||
-       (NumParams < 1) || (NumParams > 2))) {
-    // We have the wrong number of parameters.
-    unsigned ErrorKind;
-    if (CanBeUnaryOperator && CanBeBinaryOperator) {
-      ErrorKind = 2;  // 2 -> unary or binary.
-    } else if (CanBeUnaryOperator) {
-      ErrorKind = 0;  // 0 -> unary
-    } else {
-      assert(CanBeBinaryOperator &&
-             "All non-call overloaded operators are unary or binary!");
-      ErrorKind = 1;  // 1 -> binary
-    }
-
-    return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be)
-      << FnDecl->getDeclName() << NumParams << ErrorKind;
-  }
-
-  // Overloaded operators other than operator() cannot be variadic.
-  if (Op != OO_Call &&
-      FnDecl->getType()->getAs<FunctionProtoType>()->isVariadic()) {
-    return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic)
-      << FnDecl->getDeclName();
-  }
-
-  // Some operators must be non-static member functions.
-  if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) {
-    return Diag(FnDecl->getLocation(),
-                diag::err_operator_overload_must_be_member)
-      << FnDecl->getDeclName();
-  }
-
-  // C++ [over.inc]p1:
-  //   The user-defined function called operator++ implements the
-  //   prefix and postfix ++ operator. If this function is a member
-  //   function with no parameters, or a non-member function with one
-  //   parameter of class or enumeration type, it defines the prefix
-  //   increment operator ++ for objects of that type. If the function
-  //   is a member function with one parameter (which shall be of type
-  //   int) or a non-member function with two parameters (the second
-  //   of which shall be of type int), it defines the postfix
-  //   increment operator ++ for objects of that type.
-  if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) {
-    ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1);
-    QualType ParamType = LastParam->getType();
-
-    if (!ParamType->isSpecificBuiltinType(BuiltinType::Int) &&
-        !ParamType->isDependentType())
-      return Diag(LastParam->getLocation(),
-                  diag::err_operator_overload_post_incdec_must_be_int)
-        << LastParam->getType() << (Op == OO_MinusMinus);
-  }
-
-  return false;
-}
-
-static bool
-checkLiteralOperatorTemplateParameterList(Sema &SemaRef,
-                                          FunctionTemplateDecl *TpDecl) {
-  TemplateParameterList *TemplateParams = TpDecl->getTemplateParameters();
-
-  // Must have one or two template parameters.
-  if (TemplateParams->size() == 1) {
-    NonTypeTemplateParmDecl *PmDecl =
-        dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(0));
-
-    // The template parameter must be a char parameter pack.
-    if (PmDecl && PmDecl->isTemplateParameterPack() &&
-        SemaRef.Context.hasSameType(PmDecl->getType(), SemaRef.Context.CharTy))
-      return false;
-
-  } else if (TemplateParams->size() == 2) {
-    TemplateTypeParmDecl *PmType =
-        dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(0));
-    NonTypeTemplateParmDecl *PmArgs =
-        dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(1));
-
-    // The second template parameter must be a parameter pack with the
-    // first template parameter as its type.
-    if (PmType && PmArgs && !PmType->isTemplateParameterPack() &&
-        PmArgs->isTemplateParameterPack()) {
-      const TemplateTypeParmType *TArgs =
-          PmArgs->getType()->getAs<TemplateTypeParmType>();
-      if (TArgs && TArgs->getDepth() == PmType->getDepth() &&
-          TArgs->getIndex() == PmType->getIndex()) {
-        if (!SemaRef.inTemplateInstantiation())
-          SemaRef.Diag(TpDecl->getLocation(),
-                       diag::ext_string_literal_operator_template);
-        return false;
-      }
-    }
-  }
-
-  SemaRef.Diag(TpDecl->getTemplateParameters()->getSourceRange().getBegin(),
-               diag::err_literal_operator_template)
-      << TpDecl->getTemplateParameters()->getSourceRange();
-  return true;
-}
-
-/// CheckLiteralOperatorDeclaration - Check whether the declaration
-/// of this literal operator function is well-formed. If so, returns
-/// false; otherwise, emits appropriate diagnostics and returns true.
-bool Sema::CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl) {
-  if (isa<CXXMethodDecl>(FnDecl)) {
-    Diag(FnDecl->getLocation(), diag::err_literal_operator_outside_namespace)
-      << FnDecl->getDeclName();
-    return true;
-  }
-
-  if (FnDecl->isExternC()) {
-    Diag(FnDecl->getLocation(), diag::err_literal_operator_extern_c);
-    if (const LinkageSpecDecl *LSD =
-            FnDecl->getDeclContext()->getExternCContext())
-      Diag(LSD->getExternLoc(), diag::note_extern_c_begins_here);
-    return true;
-  }
-
-  // This might be the definition of a literal operator template.
-  FunctionTemplateDecl *TpDecl = FnDecl->getDescribedFunctionTemplate();
-
-  // This might be a specialization of a literal operator template.
-  if (!TpDecl)
-    TpDecl = FnDecl->getPrimaryTemplate();
-
-  // template <char...> type operator "" name() and
-  // template <class T, T...> type operator "" name() are the only valid
-  // template signatures, and the only valid signatures with no parameters.
-  if (TpDecl) {
-    if (FnDecl->param_size() != 0) {
-      Diag(FnDecl->getLocation(),
-           diag::err_literal_operator_template_with_params);
-      return true;
-    }
-
-    if (checkLiteralOperatorTemplateParameterList(*this, TpDecl))
-      return true;
-
-  } else if (FnDecl->param_size() == 1) {
-    const ParmVarDecl *Param = FnDecl->getParamDecl(0);
-
-    QualType ParamType = Param->getType().getUnqualifiedType();
-
-    // Only unsigned long long int, long double, any character type, and const
-    // char * are allowed as the only parameters.
-    if (ParamType->isSpecificBuiltinType(BuiltinType::ULongLong) ||
-        ParamType->isSpecificBuiltinType(BuiltinType::LongDouble) ||
-        Context.hasSameType(ParamType, Context.CharTy) ||
-        Context.hasSameType(ParamType, Context.WideCharTy) ||
-        Context.hasSameType(ParamType, Context.Char8Ty) ||
-        Context.hasSameType(ParamType, Context.Char16Ty) ||
-        Context.hasSameType(ParamType, Context.Char32Ty)) {
-    } else if (const PointerType *Ptr = ParamType->getAs<PointerType>()) {
-      QualType InnerType = Ptr->getPointeeType();
-
-      // Pointer parameter must be a const char *.
-      if (!(Context.hasSameType(InnerType.getUnqualifiedType(),
-                                Context.CharTy) &&
-            InnerType.isConstQualified() && !InnerType.isVolatileQualified())) {
-        Diag(Param->getSourceRange().getBegin(),
-             diag::err_literal_operator_param)
-            << ParamType << "'const char *'" << Param->getSourceRange();
-        return true;
-      }
-
-    } else if (ParamType->isRealFloatingType()) {
-      Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
-          << ParamType << Context.LongDoubleTy << Param->getSourceRange();
-      return true;
-
-    } else if (ParamType->isIntegerType()) {
-      Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
-          << ParamType << Context.UnsignedLongLongTy << Param->getSourceRange();
-      return true;
-
-    } else {
-      Diag(Param->getSourceRange().getBegin(),
-           diag::err_literal_operator_invalid_param)
-          << ParamType << Param->getSourceRange();
-      return true;
-    }
-
-  } else if (FnDecl->param_size() == 2) {
-    FunctionDecl::param_iterator Param = FnDecl->param_begin();
-
-    // First, verify that the first parameter is correct.
-
-    QualType FirstParamType = (*Param)->getType().getUnqualifiedType();
-
-    // Two parameter function must have a pointer to const as a
-    // first parameter; let's strip those qualifiers.
-    const PointerType *PT = FirstParamType->getAs<PointerType>();
-
-    if (!PT) {
-      Diag((*Param)->getSourceRange().getBegin(),
-           diag::err_literal_operator_param)
-          << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
-      return true;
-    }
-
-    QualType PointeeType = PT->getPointeeType();
-    // First parameter must be const
-    if (!PointeeType.isConstQualified() || PointeeType.isVolatileQualified()) {
-      Diag((*Param)->getSourceRange().getBegin(),
-           diag::err_literal_operator_param)
-          << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
-      return true;
-    }
-
-    QualType InnerType = PointeeType.getUnqualifiedType();
-    // Only const char *, const wchar_t*, const char8_t*, const char16_t*, and
-    // const char32_t* are allowed as the first parameter to a two-parameter
-    // function
-    if (!(Context.hasSameType(InnerType, Context.CharTy) ||
-          Context.hasSameType(InnerType, Context.WideCharTy) ||
-          Context.hasSameType(InnerType, Context.Char8Ty) ||
-          Context.hasSameType(InnerType, Context.Char16Ty) ||
-          Context.hasSameType(InnerType, Context.Char32Ty))) {
-      Diag((*Param)->getSourceRange().getBegin(),
-           diag::err_literal_operator_param)
-          << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
-      return true;
-    }
-
-    // Move on to the second and final parameter.
-    ++Param;
-
-    // The second parameter must be a std::size_t.
-    QualType SecondParamType = (*Param)->getType().getUnqualifiedType();
-    if (!Context.hasSameType(SecondParamType, Context.getSizeType())) {
-      Diag((*Param)->getSourceRange().getBegin(),
-           diag::err_literal_operator_param)
-          << SecondParamType << Context.getSizeType()
-          << (*Param)->getSourceRange();
-      return true;
-    }
-  } else {
-    Diag(FnDecl->getLocation(), diag::err_literal_operator_bad_param_count);
-    return true;
-  }
-
-  // Parameters are good.
-
-  // A parameter-declaration-clause containing a default argument is not
-  // equivalent to any of the permitted forms.
-  for (auto Param : FnDecl->parameters()) {
-    if (Param->hasDefaultArg()) {
-      Diag(Param->getDefaultArgRange().getBegin(),
-           diag::err_literal_operator_default_argument)
-        << Param->getDefaultArgRange();
-      break;
-    }
-  }
-
-  StringRef LiteralName
-    = FnDecl->getDeclName().getCXXLiteralIdentifier()->getName();
-  if (LiteralName[0] != '_' &&
-      !getSourceManager().isInSystemHeader(FnDecl->getLocation())) {
-    // C++11 [usrlit.suffix]p1:
-    //   Literal suffix identifiers that do not start with an underscore
-    //   are reserved for future standardization.
-    Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved)
-      << StringLiteralParser::isValidUDSuffix(getLangOpts(), LiteralName);
-  }
-
-  return false;
-}
-
-/// ActOnStartLinkageSpecification - Parsed the beginning of a C++
-/// linkage specification, including the language and (if present)
-/// the '{'. ExternLoc is the location of the 'extern', Lang is the
-/// language string literal. LBraceLoc, if valid, provides the location of
-/// the '{' brace. Otherwise, this linkage specification does not
-/// have any braces.
-Decl *Sema::ActOnStartLinkageSpecification(Scope *S, SourceLocation ExternLoc,
-                                           Expr *LangStr,
-                                           SourceLocation LBraceLoc) {
-  StringLiteral *Lit = cast<StringLiteral>(LangStr);
-  if (!Lit->isAscii()) {
-    Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_not_ascii)
-      << LangStr->getSourceRange();
-    return nullptr;
-  }
-
-  StringRef Lang = Lit->getString();
-  LinkageSpecDecl::LanguageIDs Language;
-  if (Lang == "C")
-    Language = LinkageSpecDecl::lang_c;
-  else if (Lang == "C++")
-    Language = LinkageSpecDecl::lang_cxx;
-  else {
-    Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_unknown)
-      << LangStr->getSourceRange();
-    return nullptr;
-  }
-
-  // FIXME: Add all the various semantics of linkage specifications
-
-  LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, ExternLoc,
-                                               LangStr->getExprLoc(), Language,
-                                               LBraceLoc.isValid());
-  CurContext->addDecl(D);
-  PushDeclContext(S, D);
-  return D;
-}
-
-/// ActOnFinishLinkageSpecification - Complete the definition of
-/// the C++ linkage specification LinkageSpec. If RBraceLoc is
-/// valid, it's the position of the closing '}' brace in a linkage
-/// specification that uses braces.
-Decl *Sema::ActOnFinishLinkageSpecification(Scope *S,
-                                            Decl *LinkageSpec,
-                                            SourceLocation RBraceLoc) {
-  if (RBraceLoc.isValid()) {
-    LinkageSpecDecl* LSDecl = cast<LinkageSpecDecl>(LinkageSpec);
-    LSDecl->setRBraceLoc(RBraceLoc);
-  }
-  PopDeclContext();
-  return LinkageSpec;
-}
-
-Decl *Sema::ActOnEmptyDeclaration(Scope *S,
-                                  const ParsedAttributesView &AttrList,
-                                  SourceLocation SemiLoc) {
-  Decl *ED = EmptyDecl::Create(Context, CurContext, SemiLoc);
-  // Attribute declarations appertain to empty declaration so we handle
-  // them here.
-  ProcessDeclAttributeList(S, ED, AttrList);
-
-  CurContext->addDecl(ED);
-  return ED;
-}
-
-/// Perform semantic analysis for the variable declaration that
-/// occurs within a C++ catch clause, returning the newly-created
-/// variable.
-VarDecl *Sema::BuildExceptionDeclaration(Scope *S,
-                                         TypeSourceInfo *TInfo,
-                                         SourceLocation StartLoc,
-                                         SourceLocation Loc,
-                                         IdentifierInfo *Name) {
-  bool Invalid = false;
-  QualType ExDeclType = TInfo->getType();
-
-  // Arrays and functions decay.
-  if (ExDeclType->isArrayType())
-    ExDeclType = Context.getArrayDecayedType(ExDeclType);
-  else if (ExDeclType->isFunctionType())
-    ExDeclType = Context.getPointerType(ExDeclType);
-
-  // C++ 15.3p1: The exception-declaration shall not denote an incomplete type.
-  // The exception-declaration shall not denote a pointer or reference to an
-  // incomplete type, other than [cv] void*.
-  // N2844 forbids rvalue references.
-  if (!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) {
-    Diag(Loc, diag::err_catch_rvalue_ref);
-    Invalid = true;
-  }
-
-  if (ExDeclType->isVariablyModifiedType()) {
-    Diag(Loc, diag::err_catch_variably_modified) << ExDeclType;
-    Invalid = true;
-  }
-
-  QualType BaseType = ExDeclType;
-  int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference
-  unsigned DK = diag::err_catch_incomplete;
-  if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
-    BaseType = Ptr->getPointeeType();
-    Mode = 1;
-    DK = diag::err_catch_incomplete_ptr;
-  } else if (const ReferenceType *Ref = BaseType->getAs<ReferenceType>()) {
-    // For the purpose of error recovery, we treat rvalue refs like lvalue refs.
-    BaseType = Ref->getPointeeType();
-    Mode = 2;
-    DK = diag::err_catch_incomplete_ref;
-  }
-  if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) &&
-      !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK))
-    Invalid = true;
-
-  if (!Invalid && !ExDeclType->isDependentType() &&
-      RequireNonAbstractType(Loc, ExDeclType,
-                             diag::err_abstract_type_in_decl,
-                             AbstractVariableType))
-    Invalid = true;
-
-  // Only the non-fragile NeXT runtime currently supports C++ catches
-  // of ObjC types, and no runtime supports catching ObjC types by value.
-  if (!Invalid && getLangOpts().ObjC) {
-    QualType T = ExDeclType;
-    if (const ReferenceType *RT = T->getAs<ReferenceType>())
-      T = RT->getPointeeType();
-
-    if (T->isObjCObjectType()) {
-      Diag(Loc, diag::err_objc_object_catch);
-      Invalid = true;
-    } else if (T->isObjCObjectPointerType()) {
-      // FIXME: should this be a test for macosx-fragile specifically?
-      if (getLangOpts().ObjCRuntime.isFragile())
-        Diag(Loc, diag::warn_objc_pointer_cxx_catch_fragile);
-    }
-  }
-
-  VarDecl *ExDecl = VarDecl::Create(Context, CurContext, StartLoc, Loc, Name,
-                                    ExDeclType, TInfo, SC_None);
-  ExDecl->setExceptionVariable(true);
-
-  // In ARC, infer 'retaining' for variables of retainable type.
-  if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(ExDecl))
-    Invalid = true;
-
-  if (!Invalid && !ExDeclType->isDependentType()) {
-    if (const RecordType *recordType = ExDeclType->getAs<RecordType>()) {
-      // Insulate this from anything else we might currently be parsing.
-      EnterExpressionEvaluationContext scope(
-          *this, ExpressionEvaluationContext::PotentiallyEvaluated);
-
-      // C++ [except.handle]p16:
-      //   The object declared in an exception-declaration or, if the
-      //   exception-declaration does not specify a name, a temporary (12.2) is
-      //   copy-initialized (8.5) from the exception object. [...]
-      //   The object is destroyed when the handler exits, after the destruction
-      //   of any automatic objects initialized within the handler.
-      //
-      // We just pretend to initialize the object with itself, then make sure
-      // it can be destroyed later.
-      QualType initType = Context.getExceptionObjectType(ExDeclType);
-
-      InitializedEntity entity =
-        InitializedEntity::InitializeVariable(ExDecl);
-      InitializationKind initKind =
-        InitializationKind::CreateCopy(Loc, SourceLocation());
-
-      Expr *opaqueValue =
-        new (Context) OpaqueValueExpr(Loc, initType, VK_LValue, OK_Ordinary);
-      InitializationSequence sequence(*this, entity, initKind, opaqueValue);
-      ExprResult result = sequence.Perform(*this, entity, initKind, opaqueValue);
-      if (result.isInvalid())
-        Invalid = true;
-      else {
-        // If the constructor used was non-trivial, set this as the
-        // "initializer".
-        CXXConstructExpr *construct = result.getAs<CXXConstructExpr>();
-        if (!construct->getConstructor()->isTrivial()) {
-          Expr *init = MaybeCreateExprWithCleanups(construct);
-          ExDecl->setInit(init);
-        }
-
-        // And make sure it's destructable.
-        FinalizeVarWithDestructor(ExDecl, recordType);
-      }
-    }
-  }
-
-  if (Invalid)
-    ExDecl->setInvalidDecl();
-
-  return ExDecl;
-}
-
-/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch
-/// handler.
-Decl *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) {
-  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
-  bool Invalid = D.isInvalidType();
-
-  // Check for unexpanded parameter packs.
-  if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
-                                      UPPC_ExceptionType)) {
-    TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
-                                             D.getIdentifierLoc());
-    Invalid = true;
-  }
-
-  IdentifierInfo *II = D.getIdentifier();
-  if (NamedDecl *PrevDecl = LookupSingleName(S, II, D.getIdentifierLoc(),
-                                             LookupOrdinaryName,
-                                             ForVisibleRedeclaration)) {
-    // The scope should be freshly made just for us. There is just no way
-    // it contains any previous declaration, except for function parameters in
-    // a function-try-block's catch statement.
-    assert(!S->isDeclScope(PrevDecl));
-    if (isDeclInScope(PrevDecl, CurContext, S)) {
-      Diag(D.getIdentifierLoc(), diag::err_redefinition)
-        << D.getIdentifier();
-      Diag(PrevDecl->getLocation(), diag::note_previous_definition);
-      Invalid = true;
-    } else if (PrevDecl->isTemplateParameter())
-      // Maybe we will complain about the shadowed template parameter.
-      DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
-  }
-
-  if (D.getCXXScopeSpec().isSet() && !Invalid) {
-    Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator)
-      << D.getCXXScopeSpec().getRange();
-    Invalid = true;
-  }
-
-  VarDecl *ExDecl = BuildExceptionDeclaration(
-      S, TInfo, D.getBeginLoc(), D.getIdentifierLoc(), D.getIdentifier());
-  if (Invalid)
-    ExDecl->setInvalidDecl();
-
-  // Add the exception declaration into this scope.
-  if (II)
-    PushOnScopeChains(ExDecl, S);
-  else
-    CurContext->addDecl(ExDecl);
-
-  ProcessDeclAttributes(S, ExDecl, D);
-  return ExDecl;
-}
-
-Decl *Sema::ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
-                                         Expr *AssertExpr,
-                                         Expr *AssertMessageExpr,
-                                         SourceLocation RParenLoc) {
-  StringLiteral *AssertMessage =
-      AssertMessageExpr ? cast<StringLiteral>(AssertMessageExpr) : nullptr;
-
-  if (DiagnoseUnexpandedParameterPack(AssertExpr, UPPC_StaticAssertExpression))
-    return nullptr;
-
-  return BuildStaticAssertDeclaration(StaticAssertLoc, AssertExpr,
-                                      AssertMessage, RParenLoc, false);
-}
-
-Decl *Sema::BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
-                                         Expr *AssertExpr,
-                                         StringLiteral *AssertMessage,
-                                         SourceLocation RParenLoc,
-                                         bool Failed) {
-  assert(AssertExpr != nullptr && "Expected non-null condition");
-  if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent() &&
-      !Failed) {
-    // In a static_assert-declaration, the constant-expression shall be a
-    // constant expression that can be contextually converted to bool.
-    ExprResult Converted = PerformContextuallyConvertToBool(AssertExpr);
-    if (Converted.isInvalid())
-      Failed = true;
-    else
-      Converted = ConstantExpr::Create(Context, Converted.get());
-
-    llvm::APSInt Cond;
-    if (!Failed && VerifyIntegerConstantExpression(Converted.get(), &Cond,
-          diag::err_static_assert_expression_is_not_constant,
-          /*AllowFold=*/false).isInvalid())
-      Failed = true;
-
-    if (!Failed && !Cond) {
-      SmallString<256> MsgBuffer;
-      llvm::raw_svector_ostream Msg(MsgBuffer);
-      if (AssertMessage)
-        AssertMessage->printPretty(Msg, nullptr, getPrintingPolicy());
-
-      Expr *InnerCond = nullptr;
-      std::string InnerCondDescription;
-      std::tie(InnerCond, InnerCondDescription) =
-        findFailedBooleanCondition(Converted.get());
-      if (InnerCond && !isa<CXXBoolLiteralExpr>(InnerCond)
-                    && !isa<IntegerLiteral>(InnerCond)) {
-        Diag(StaticAssertLoc, diag::err_static_assert_requirement_failed)
-          << InnerCondDescription << !AssertMessage
-          << Msg.str() << InnerCond->getSourceRange();
-      } else {
-        Diag(StaticAssertLoc, diag::err_static_assert_failed)
-          << !AssertMessage << Msg.str() << AssertExpr->getSourceRange();
-      }
-      Failed = true;
-    }
-  }
-
-  ExprResult FullAssertExpr = ActOnFinishFullExpr(AssertExpr, StaticAssertLoc,
-                                                  /*DiscardedValue*/false,
-                                                  /*IsConstexpr*/true);
-  if (FullAssertExpr.isInvalid())
-    Failed = true;
-  else
-    AssertExpr = FullAssertExpr.get();
-
-  Decl *Decl = StaticAssertDecl::Create(Context, CurContext, StaticAssertLoc,
-                                        AssertExpr, AssertMessage, RParenLoc,
-                                        Failed);
-
-  CurContext->addDecl(Decl);
-  return Decl;
-}
-
-/// Perform semantic analysis of the given friend type declaration.
-///
-/// \returns A friend declaration that.
-FriendDecl *Sema::CheckFriendTypeDecl(SourceLocation LocStart,
-                                      SourceLocation FriendLoc,
-                                      TypeSourceInfo *TSInfo) {
-  assert(TSInfo && "NULL TypeSourceInfo for friend type declaration");
-
-  QualType T = TSInfo->getType();
-  SourceRange TypeRange = TSInfo->getTypeLoc().getLocalSourceRange();
-
-  // C++03 [class.friend]p2:
-  //   An elaborated-type-specifier shall be used in a friend declaration
-  //   for a class.*
-  //
-  //   * The class-key of the elaborated-type-specifier is required.
-  if (!CodeSynthesisContexts.empty()) {
-    // Do not complain about the form of friend template types during any kind
-    // of code synthesis. For template instantiation, we will have complained
-    // when the template was defined.
-  } else {
-    if (!T->isElaboratedTypeSpecifier()) {
-      // If we evaluated the type to a record type, suggest putting
-      // a tag in front.
-      if (const RecordType *RT = T->getAs<RecordType>()) {
-        RecordDecl *RD = RT->getDecl();
-
-        SmallString<16> InsertionText(" ");
-        InsertionText += RD->getKindName();
-
-        Diag(TypeRange.getBegin(),
-             getLangOpts().CPlusPlus11 ?
-               diag::warn_cxx98_compat_unelaborated_friend_type :
-               diag::ext_unelaborated_friend_type)
-          << (unsigned) RD->getTagKind()
-          << T
-          << FixItHint::CreateInsertion(getLocForEndOfToken(FriendLoc),
-                                        InsertionText);
-      } else {
-        Diag(FriendLoc,
-             getLangOpts().CPlusPlus11 ?
-               diag::warn_cxx98_compat_nonclass_type_friend :
-               diag::ext_nonclass_type_friend)
-          << T
-          << TypeRange;
-      }
-    } else if (T->getAs<EnumType>()) {
-      Diag(FriendLoc,
-           getLangOpts().CPlusPlus11 ?
-             diag::warn_cxx98_compat_enum_friend :
-             diag::ext_enum_friend)
-        << T
-        << TypeRange;
-    }
-
-    // C++11 [class.friend]p3:
-    //   A friend declaration that does not declare a function shall have one
-    //   of the following forms:
-    //     friend elaborated-type-specifier ;
-    //     friend simple-type-specifier ;
-    //     friend typename-specifier ;
-    if (getLangOpts().CPlusPlus11 && LocStart != FriendLoc)
-      Diag(FriendLoc, diag::err_friend_not_first_in_declaration) << T;
-  }
-
-  //   If the type specifier in a friend declaration designates a (possibly
-  //   cv-qualified) class type, that class is declared as a friend; otherwise,
-  //   the friend declaration is ignored.
-  return FriendDecl::Create(Context, CurContext,
-                            TSInfo->getTypeLoc().getBeginLoc(), TSInfo,
-                            FriendLoc);
-}
-
-/// Handle a friend tag declaration where the scope specifier was
-/// templated.
-Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
-                                    unsigned TagSpec, SourceLocation TagLoc,
-                                    CXXScopeSpec &SS, IdentifierInfo *Name,
-                                    SourceLocation NameLoc,
-                                    const ParsedAttributesView &Attr,
-                                    MultiTemplateParamsArg TempParamLists) {
-  TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
-
-  bool IsMemberSpecialization = false;
-  bool Invalid = false;
-
-  if (TemplateParameterList *TemplateParams =
-          MatchTemplateParametersToScopeSpecifier(
-              TagLoc, NameLoc, SS, nullptr, TempParamLists, /*friend*/ true,
-              IsMemberSpecialization, Invalid)) {
-    if (TemplateParams->size() > 0) {
-      // This is a declaration of a class template.
-      if (Invalid)
-        return nullptr;
-
-      return CheckClassTemplate(S, TagSpec, TUK_Friend, TagLoc, SS, Name,
-                                NameLoc, Attr, TemplateParams, AS_public,
-                                /*ModulePrivateLoc=*/SourceLocation(),
-                                FriendLoc, TempParamLists.size() - 1,
-                                TempParamLists.data()).get();
-    } else {
-      // The "template<>" header is extraneous.
-      Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
-        << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
-      IsMemberSpecialization = true;
-    }
-  }
-
-  if (Invalid) return nullptr;
-
-  bool isAllExplicitSpecializations = true;
-  for (unsigned I = TempParamLists.size(); I-- > 0; ) {
-    if (TempParamLists[I]->size()) {
-      isAllExplicitSpecializations = false;
-      break;
-    }
-  }
-
-  // FIXME: don't ignore attributes.
-
-  // If it's explicit specializations all the way down, just forget
-  // about the template header and build an appropriate non-templated
-  // friend.  TODO: for source fidelity, remember the headers.
-  if (isAllExplicitSpecializations) {
-    if (SS.isEmpty()) {
-      bool Owned = false;
-      bool IsDependent = false;
-      return ActOnTag(S, TagSpec, TUK_Friend, TagLoc, SS, Name, NameLoc,
-                      Attr, AS_public,
-                      /*ModulePrivateLoc=*/SourceLocation(),
-                      MultiTemplateParamsArg(), Owned, IsDependent,
-                      /*ScopedEnumKWLoc=*/SourceLocation(),
-                      /*ScopedEnumUsesClassTag=*/false,
-                      /*UnderlyingType=*/TypeResult(),
-                      /*IsTypeSpecifier=*/false,
-                      /*IsTemplateParamOrArg=*/false);
-    }
-
-    NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
-    ElaboratedTypeKeyword Keyword
-      = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
-    QualType T = CheckTypenameType(Keyword, TagLoc, QualifierLoc,
-                                   *Name, NameLoc);
-    if (T.isNull())
-      return nullptr;
-
-    TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
-    if (isa<DependentNameType>(T)) {
-      DependentNameTypeLoc TL =
-          TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
-      TL.setElaboratedKeywordLoc(TagLoc);
-      TL.setQualifierLoc(QualifierLoc);
-      TL.setNameLoc(NameLoc);
-    } else {
-      ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
-      TL.setElaboratedKeywordLoc(TagLoc);
-      TL.setQualifierLoc(QualifierLoc);
-      TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(NameLoc);
-    }
-
-    FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
-                                            TSI, FriendLoc, TempParamLists);
-    Friend->setAccess(AS_public);
-    CurContext->addDecl(Friend);
-    return Friend;
-  }
-
-  assert(SS.isNotEmpty() && "valid templated tag with no SS and no direct?");
-
-
-
-  // Handle the case of a templated-scope friend class.  e.g.
-  //   template <class T> class A<T>::B;
-  // FIXME: we don't support these right now.
-  Diag(NameLoc, diag::warn_template_qualified_friend_unsupported)
-    << SS.getScopeRep() << SS.getRange() << cast<CXXRecordDecl>(CurContext);
-  ElaboratedTypeKeyword ETK = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
-  QualType T = Context.getDependentNameType(ETK, SS.getScopeRep(), Name);
-  TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
-  DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
-  TL.setElaboratedKeywordLoc(TagLoc);
-  TL.setQualifierLoc(SS.getWithLocInContext(Context));
-  TL.setNameLoc(NameLoc);
-
-  FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
-                                          TSI, FriendLoc, TempParamLists);
-  Friend->setAccess(AS_public);
-  Friend->setUnsupportedFriend(true);
-  CurContext->addDecl(Friend);
-  return Friend;
-}
-
-/// Handle a friend type declaration.  This works in tandem with
-/// ActOnTag.
-///
-/// Notes on friend class templates:
-///
-/// We generally treat friend class declarations as if they were
-/// declaring a class.  So, for example, the elaborated type specifier
-/// in a friend declaration is required to obey the restrictions of a
-/// class-head (i.e. no typedefs in the scope chain), template
-/// parameters are required to match up with simple template-ids, &c.
-/// However, unlike when declaring a template specialization, it's
-/// okay to refer to a template specialization without an empty
-/// template parameter declaration, e.g.
-///   friend class A<T>::B<unsigned>;
-/// We permit this as a special case; if there are any template
-/// parameters present at all, require proper matching, i.e.
-///   template <> template \<class T> friend class A<int>::B;
-Decl *Sema::ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
-                                MultiTemplateParamsArg TempParams) {
-  SourceLocation Loc = DS.getBeginLoc();
-
-  assert(DS.isFriendSpecified());
-  assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
-
-  // C++ [class.friend]p3:
-  // A friend declaration that does not declare a function shall have one of
-  // the following forms:
-  //     friend elaborated-type-specifier ;
-  //     friend simple-type-specifier ;
-  //     friend typename-specifier ;
-  //
-  // Any declaration with a type qualifier does not have that form. (It's
-  // legal to specify a qualified type as a friend, you just can't write the
-  // keywords.)
-  if (DS.getTypeQualifiers()) {
-    if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
-      Diag(DS.getConstSpecLoc(), diag::err_friend_decl_spec) << "const";
-    if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
-      Diag(DS.getVolatileSpecLoc(), diag::err_friend_decl_spec) << "volatile";
-    if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
-      Diag(DS.getRestrictSpecLoc(), diag::err_friend_decl_spec) << "restrict";
-    if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
-      Diag(DS.getAtomicSpecLoc(), diag::err_friend_decl_spec) << "_Atomic";
-    if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
-      Diag(DS.getUnalignedSpecLoc(), diag::err_friend_decl_spec) << "__unaligned";
-  }
-
-  // Try to convert the decl specifier to a type.  This works for
-  // friend templates because ActOnTag never produces a ClassTemplateDecl
-  // for a TUK_Friend.
-  Declarator TheDeclarator(DS, DeclaratorContext::MemberContext);
-  TypeSourceInfo *TSI = GetTypeForDeclarator(TheDeclarator, S);
-  QualType T = TSI->getType();
-  if (TheDeclarator.isInvalidType())
-    return nullptr;
-
-  if (DiagnoseUnexpandedParameterPack(Loc, TSI, UPPC_FriendDeclaration))
-    return nullptr;
-
-  // This is definitely an error in C++98.  It's probably meant to
-  // be forbidden in C++0x, too, but the specification is just
-  // poorly written.
-  //
-  // The problem is with declarations like the following:
-  //   template <T> friend A<T>::foo;
-  // where deciding whether a class C is a friend or not now hinges
-  // on whether there exists an instantiation of A that causes
-  // 'foo' to equal C.  There are restrictions on class-heads
-  // (which we declare (by fiat) elaborated friend declarations to
-  // be) that makes this tractable.
-  //
-  // FIXME: handle "template <> friend class A<T>;", which
-  // is possibly well-formed?  Who even knows?
-  if (TempParams.size() && !T->isElaboratedTypeSpecifier()) {
-    Diag(Loc, diag::err_tagless_friend_type_template)
-      << DS.getSourceRange();
-    return nullptr;
-  }
-
-  // C++98 [class.friend]p1: A friend of a class is a function
-  //   or class that is not a member of the class . . .
-  // This is fixed in DR77, which just barely didn't make the C++03
-  // deadline.  It's also a very silly restriction that seriously
-  // affects inner classes and which nobody else seems to implement;
-  // thus we never diagnose it, not even in -pedantic.
-  //
-  // But note that we could warn about it: it's always useless to
-  // friend one of your own members (it's not, however, worthless to
-  // friend a member of an arbitrary specialization of your template).
-
-  Decl *D;
-  if (!TempParams.empty())
-    D = FriendTemplateDecl::Create(Context, CurContext, Loc,
-                                   TempParams,
-                                   TSI,
-                                   DS.getFriendSpecLoc());
-  else
-    D = CheckFriendTypeDecl(Loc, DS.getFriendSpecLoc(), TSI);
-
-  if (!D)
-    return nullptr;
-
-  D->setAccess(AS_public);
-  CurContext->addDecl(D);
-
-  return D;
-}
-
-NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
-                                        MultiTemplateParamsArg TemplateParams) {
-  const DeclSpec &DS = D.getDeclSpec();
-
-  assert(DS.isFriendSpecified());
-  assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
-
-  SourceLocation Loc = D.getIdentifierLoc();
-  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
-
-  // C++ [class.friend]p1
-  //   A friend of a class is a function or class....
-  // Note that this sees through typedefs, which is intended.
-  // It *doesn't* see through dependent types, which is correct
-  // according to [temp.arg.type]p3:
-  //   If a declaration acquires a function type through a
-  //   type dependent on a template-parameter and this causes
-  //   a declaration that does not use the syntactic form of a
-  //   function declarator to have a function type, the program
-  //   is ill-formed.
-  if (!TInfo->getType()->isFunctionType()) {
-    Diag(Loc, diag::err_unexpected_friend);
-
-    // It might be worthwhile to try to recover by creating an
-    // appropriate declaration.
-    return nullptr;
-  }
-
-  // C++ [namespace.memdef]p3
-  //  - If a friend declaration in a non-local class first declares a
-  //    class or function, the friend class or function is a member
-  //    of the innermost enclosing namespace.
-  //  - The name of the friend is not found by simple name lookup
-  //    until a matching declaration is provided in that namespace
-  //    scope (either before or after the class declaration granting
-  //    friendship).
-  //  - If a friend function is called, its name may be found by the
-  //    name lookup that considers functions from namespaces and
-  //    classes associated with the types of the function arguments.
-  //  - When looking for a prior declaration of a class or a function
-  //    declared as a friend, scopes outside the innermost enclosing
-  //    namespace scope are not considered.
-
-  CXXScopeSpec &SS = D.getCXXScopeSpec();
-  DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
-  assert(NameInfo.getName());
-
-  // Check for unexpanded parameter packs.
-  if (DiagnoseUnexpandedParameterPack(Loc, TInfo, UPPC_FriendDeclaration) ||
-      DiagnoseUnexpandedParameterPack(NameInfo, UPPC_FriendDeclaration) ||
-      DiagnoseUnexpandedParameterPack(SS, UPPC_FriendDeclaration))
-    return nullptr;
-
-  // The context we found the declaration in, or in which we should
-  // create the declaration.
-  DeclContext *DC;
-  Scope *DCScope = S;
-  LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
-                        ForExternalRedeclaration);
-
-  // There are five cases here.
-  //   - There's no scope specifier and we're in a local class. Only look
-  //     for functions declared in the immediately-enclosing block scope.
-  // We recover from invalid scope qualifiers as if they just weren't there.
-  FunctionDecl *FunctionContainingLocalClass = nullptr;
-  if ((SS.isInvalid() || !SS.isSet()) &&
-      (FunctionContainingLocalClass =
-           cast<CXXRecordDecl>(CurContext)->isLocalClass())) {
-    // C++11 [class.friend]p11:
-    //   If a friend declaration appears in a local class and the name
-    //   specified is an unqualified name, a prior declaration is
-    //   looked up without considering scopes that are outside the
-    //   innermost enclosing non-class scope. For a friend function
-    //   declaration, if there is no prior declaration, the program is
-    //   ill-formed.
-
-    // Find the innermost enclosing non-class scope. This is the block
-    // scope containing the local class definition (or for a nested class,
-    // the outer local class).
-    DCScope = S->getFnParent();
-
-    // Look up the function name in the scope.
-    Previous.clear(LookupLocalFriendName);
-    LookupName(Previous, S, /*AllowBuiltinCreation*/false);
-
-    if (!Previous.empty()) {
-      // All possible previous declarations must have the same context:
-      // either they were declared at block scope or they are members of
-      // one of the enclosing local classes.
-      DC = Previous.getRepresentativeDecl()->getDeclContext();
-    } else {
-      // This is ill-formed, but provide the context that we would have
-      // declared the function in, if we were permitted to, for error recovery.
-      DC = FunctionContainingLocalClass;
-    }
-    adjustContextForLocalExternDecl(DC);
-
-    // C++ [class.friend]p6:
-    //   A function can be defined in a friend declaration of a class if and
-    //   only if the class is a non-local class (9.8), the function name is
-    //   unqualified, and the function has namespace scope.
-    if (D.isFunctionDefinition()) {
-      Diag(NameInfo.getBeginLoc(), diag::err_friend_def_in_local_class);
-    }
-
-  //   - There's no scope specifier, in which case we just go to the
-  //     appropriate scope and look for a function or function template
-  //     there as appropriate.
-  } else if (SS.isInvalid() || !SS.isSet()) {
-    // C++11 [namespace.memdef]p3:
-    //   If the name in a friend declaration is neither qualified nor
-    //   a template-id and the declaration is a function or an
-    //   elaborated-type-specifier, the lookup to determine whether
-    //   the entity has been previously declared shall not consider
-    //   any scopes outside the innermost enclosing namespace.
-    bool isTemplateId =
-        D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId;
-
-    // Find the appropriate context according to the above.
-    DC = CurContext;
-
-    // Skip class contexts.  If someone can cite chapter and verse
-    // for this behavior, that would be nice --- it's what GCC and
-    // EDG do, and it seems like a reasonable intent, but the spec
-    // really only says that checks for unqualified existing
-    // declarations should stop at the nearest enclosing namespace,
-    // not that they should only consider the nearest enclosing
-    // namespace.
-    while (DC->isRecord())
-      DC = DC->getParent();
-
-    DeclContext *LookupDC = DC;
-    while (LookupDC->isTransparentContext())
-      LookupDC = LookupDC->getParent();
-
-    while (true) {
-      LookupQualifiedName(Previous, LookupDC);
-
-      if (!Previous.empty()) {
-        DC = LookupDC;
-        break;
-      }
-
-      if (isTemplateId) {
-        if (isa<TranslationUnitDecl>(LookupDC)) break;
-      } else {
-        if (LookupDC->isFileContext()) break;
-      }
-      LookupDC = LookupDC->getParent();
-    }
-
-    DCScope = getScopeForDeclContext(S, DC);
-
-  //   - There's a non-dependent scope specifier, in which case we
-  //     compute it and do a previous lookup there for a function
-  //     or function template.
-  } else if (!SS.getScopeRep()->isDependent()) {
-    DC = computeDeclContext(SS);
-    if (!DC) return nullptr;
-
-    if (RequireCompleteDeclContext(SS, DC)) return nullptr;
-
-    LookupQualifiedName(Previous, DC);
-
-    // C++ [class.friend]p1: A friend of a class is a function or
-    //   class that is not a member of the class . . .
-    if (DC->Equals(CurContext))
-      Diag(DS.getFriendSpecLoc(),
-           getLangOpts().CPlusPlus11 ?
-             diag::warn_cxx98_compat_friend_is_member :
-             diag::err_friend_is_member);
-
-    if (D.isFunctionDefinition()) {
-      // C++ [class.friend]p6:
-      //   A function can be defined in a friend declaration of a class if and
-      //   only if the class is a non-local class (9.8), the function name is
-      //   unqualified, and the function has namespace scope.
-      //
-      // FIXME: We should only do this if the scope specifier names the
-      // innermost enclosing namespace; otherwise the fixit changes the
-      // meaning of the code.
-      SemaDiagnosticBuilder DB
-        = Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def);
-
-      DB << SS.getScopeRep();
-      if (DC->isFileContext())
-        DB << FixItHint::CreateRemoval(SS.getRange());
-      SS.clear();
-    }
-
-  //   - There's a scope specifier that does not match any template
-  //     parameter lists, in which case we use some arbitrary context,
-  //     create a method or method template, and wait for instantiation.
-  //   - There's a scope specifier that does match some template
-  //     parameter lists, which we don't handle right now.
-  } else {
-    if (D.isFunctionDefinition()) {
-      // C++ [class.friend]p6:
-      //   A function can be defined in a friend declaration of a class if and
-      //   only if the class is a non-local class (9.8), the function name is
-      //   unqualified, and the function has namespace scope.
-      Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def)
-        << SS.getScopeRep();
-    }
-
-    DC = CurContext;
-    assert(isa<CXXRecordDecl>(DC) && "friend declaration not in class?");
-  }
-
-  if (!DC->isRecord()) {
-    int DiagArg = -1;
-    switch (D.getName().getKind()) {
-    case UnqualifiedIdKind::IK_ConstructorTemplateId:
-    case UnqualifiedIdKind::IK_ConstructorName:
-      DiagArg = 0;
-      break;
-    case UnqualifiedIdKind::IK_DestructorName:
-      DiagArg = 1;
-      break;
-    case UnqualifiedIdKind::IK_ConversionFunctionId:
-      DiagArg = 2;
-      break;
-    case UnqualifiedIdKind::IK_DeductionGuideName:
-      DiagArg = 3;
-      break;
-    case UnqualifiedIdKind::IK_Identifier:
-    case UnqualifiedIdKind::IK_ImplicitSelfParam:
-    case UnqualifiedIdKind::IK_LiteralOperatorId:
-    case UnqualifiedIdKind::IK_OperatorFunctionId:
-    case UnqualifiedIdKind::IK_TemplateId:
-      break;
-    }
-    // This implies that it has to be an operator or function.
-    if (DiagArg >= 0) {
-      Diag(Loc, diag::err_introducing_special_friend) << DiagArg;
-      return nullptr;
-    }
-  }
-
-  // FIXME: This is an egregious hack to cope with cases where the scope stack
-  // does not contain the declaration context, i.e., in an out-of-line
-  // definition of a class.
-  Scope FakeDCScope(S, Scope::DeclScope, Diags);
-  if (!DCScope) {
-    FakeDCScope.setEntity(DC);
-    DCScope = &FakeDCScope;
-  }
-
-  bool AddToScope = true;
-  NamedDecl *ND = ActOnFunctionDeclarator(DCScope, D, DC, TInfo, Previous,
-                                          TemplateParams, AddToScope);
-  if (!ND) return nullptr;
-
-  assert(ND->getLexicalDeclContext() == CurContext);
-
-  // If we performed typo correction, we might have added a scope specifier
-  // and changed the decl context.
-  DC = ND->getDeclContext();
-
-  // Add the function declaration to the appropriate lookup tables,
-  // adjusting the redeclarations list as necessary.  We don't
-  // want to do this yet if the friending class is dependent.
-  //
-  // Also update the scope-based lookup if the target context's
-  // lookup context is in lexical scope.
-  if (!CurContext->isDependentContext()) {
-    DC = DC->getRedeclContext();
-    DC->makeDeclVisibleInContext(ND);
-    if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
-      PushOnScopeChains(ND, EnclosingScope, /*AddToContext=*/ false);
-  }
-
-  FriendDecl *FrD = FriendDecl::Create(Context, CurContext,
-                                       D.getIdentifierLoc(), ND,
-                                       DS.getFriendSpecLoc());
-  FrD->setAccess(AS_public);
-  CurContext->addDecl(FrD);
-
-  if (ND->isInvalidDecl()) {
-    FrD->setInvalidDecl();
-  } else {
-    if (DC->isRecord()) CheckFriendAccess(ND);
-
-    FunctionDecl *FD;
-    if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
-      FD = FTD->getTemplatedDecl();
-    else
-      FD = cast<FunctionDecl>(ND);
-
-    // C++11 [dcl.fct.default]p4: If a friend declaration specifies a
-    // default argument expression, that declaration shall be a definition
-    // and shall be the only declaration of the function or function
-    // template in the translation unit.
-    if (functionDeclHasDefaultArgument(FD)) {
-      // We can't look at FD->getPreviousDecl() because it may not have been set
-      // if we're in a dependent context. If the function is known to be a
-      // redeclaration, we will have narrowed Previous down to the right decl.
-      if (D.isRedeclaration()) {
-        Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
-        Diag(Previous.getRepresentativeDecl()->getLocation(),
-             diag::note_previous_declaration);
-      } else if (!D.isFunctionDefinition())
-        Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_must_be_def);
-    }
-
-    // Mark templated-scope function declarations as unsupported.
-    if (FD->getNumTemplateParameterLists() && SS.isValid()) {
-      Diag(FD->getLocation(), diag::warn_template_qualified_friend_unsupported)
-        << SS.getScopeRep() << SS.getRange()
-        << cast<CXXRecordDecl>(CurContext);
-      FrD->setUnsupportedFriend(true);
-    }
-  }
-
-  return ND;
-}
-
-void Sema::SetDeclDeleted(Decl *Dcl, SourceLocation DelLoc) {
-  AdjustDeclIfTemplate(Dcl);
-
-  FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(Dcl);
-  if (!Fn) {
-    Diag(DelLoc, diag::err_deleted_non_function);
-    return;
-  }
-
-  // Deleted function does not have a body.
-  Fn->setWillHaveBody(false);
-
-  if (const FunctionDecl *Prev = Fn->getPreviousDecl()) {
-    // Don't consider the implicit declaration we generate for explicit
-    // specializations. FIXME: Do not generate these implicit declarations.
-    if ((Prev->getTemplateSpecializationKind() != TSK_ExplicitSpecialization ||
-         Prev->getPreviousDecl()) &&
-        !Prev->isDefined()) {
-      Diag(DelLoc, diag::err_deleted_decl_not_first);
-      Diag(Prev->getLocation().isInvalid() ? DelLoc : Prev->getLocation(),
-           Prev->isImplicit() ? diag::note_previous_implicit_declaration
-                              : diag::note_previous_declaration);
-    }
-    // If the declaration wasn't the first, we delete the function anyway for
-    // recovery.
-    Fn = Fn->getCanonicalDecl();
-  }
-
-  // dllimport/dllexport cannot be deleted.
-  if (const InheritableAttr *DLLAttr = getDLLAttr(Fn)) {
-    Diag(Fn->getLocation(), diag::err_attribute_dll_deleted) << DLLAttr;
-    Fn->setInvalidDecl();
-  }
-
-  if (Fn->isDeleted())
-    return;
-
-  // See if we're deleting a function which is already known to override a
-  // non-deleted virtual function.
-  if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn)) {
-    bool IssuedDiagnostic = false;
-    for (const CXXMethodDecl *O : MD->overridden_methods()) {
-      if (!(*MD->begin_overridden_methods())->isDeleted()) {
-        if (!IssuedDiagnostic) {
-          Diag(DelLoc, diag::err_deleted_override) << MD->getDeclName();
-          IssuedDiagnostic = true;
-        }
-        Diag(O->getLocation(), diag::note_overridden_virtual_function);
-      }
-    }
-    // If this function was implicitly deleted because it was defaulted,
-    // explain why it was deleted.
-    if (IssuedDiagnostic && MD->isDefaulted())
-      ShouldDeleteSpecialMember(MD, getSpecialMember(MD), nullptr,
-                                /*Diagnose*/true);
-  }
-
-  // C++11 [basic.start.main]p3:
-  //   A program that defines main as deleted [...] is ill-formed.
-  if (Fn->isMain())
-    Diag(DelLoc, diag::err_deleted_main);
-
-  // C++11 [dcl.fct.def.delete]p4:
-  //  A deleted function is implicitly inline.
-  Fn->setImplicitlyInline();
-  Fn->setDeletedAsWritten();
-}
-
-void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
-  CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Dcl);
-
-  if (MD) {
-    if (MD->getParent()->isDependentType()) {
-      MD->setDefaulted();
-      MD->setExplicitlyDefaulted();
-      return;
-    }
-
-    CXXSpecialMember Member = getSpecialMember(MD);
-    if (Member == CXXInvalid) {
-      if (!MD->isInvalidDecl())
-        Diag(DefaultLoc, diag::err_default_special_members);
-      return;
-    }
-
-    MD->setDefaulted();
-    MD->setExplicitlyDefaulted();
-
-    // Unset that we will have a body for this function. We might not,
-    // if it turns out to be trivial, and we don't need this marking now
-    // that we've marked it as defaulted.
-    MD->setWillHaveBody(false);
-
-    // If this definition appears within the record, do the checking when
-    // the record is complete.
-    const FunctionDecl *Primary = MD;
-    if (const FunctionDecl *Pattern = MD->getTemplateInstantiationPattern())
-      // Ask the template instantiation pattern that actually had the
-      // '= default' on it.
-      Primary = Pattern;
-
-    // If the method was defaulted on its first declaration, we will have
-    // already performed the checking in CheckCompletedCXXClass. Such a
-    // declaration doesn't trigger an implicit definition.
-    if (Primary->getCanonicalDecl()->isDefaulted())
-      return;
-
-    CheckExplicitlyDefaultedSpecialMember(MD);
-
-    if (!MD->isInvalidDecl())
-      DefineImplicitSpecialMember(*this, MD, DefaultLoc);
-  } else {
-    Diag(DefaultLoc, diag::err_default_special_members);
-  }
-}
-
-static void SearchForReturnInStmt(Sema &Self, Stmt *S) {
-  for (Stmt *SubStmt : S->children()) {
-    if (!SubStmt)
-      continue;
-    if (isa<ReturnStmt>(SubStmt))
-      Self.Diag(SubStmt->getBeginLoc(),
-                diag::err_return_in_constructor_handler);
-    if (!isa<Expr>(SubStmt))
-      SearchForReturnInStmt(Self, SubStmt);
-  }
-}
-
-void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) {
-  for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) {
-    CXXCatchStmt *Handler = TryBlock->getHandler(I);
-    SearchForReturnInStmt(*this, Handler);
-  }
-}
-
-bool Sema::CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
-                                             const CXXMethodDecl *Old) {
-  const auto *NewFT = New->getType()->getAs<FunctionProtoType>();
-  const auto *OldFT = Old->getType()->getAs<FunctionProtoType>();
-
-  if (OldFT->hasExtParameterInfos()) {
-    for (unsigned I = 0, E = OldFT->getNumParams(); I != E; ++I)
-      // A parameter of the overriding method should be annotated with noescape
-      // if the corresponding parameter of the overridden method is annotated.
-      if (OldFT->getExtParameterInfo(I).isNoEscape() &&
-          !NewFT->getExtParameterInfo(I).isNoEscape()) {
-        Diag(New->getParamDecl(I)->getLocation(),
-             diag::warn_overriding_method_missing_noescape);
-        Diag(Old->getParamDecl(I)->getLocation(),
-             diag::note_overridden_marked_noescape);
-      }
-  }
-
-  // Virtual overrides must have the same code_seg.
-  const auto *OldCSA = Old->getAttr<CodeSegAttr>();
-  const auto *NewCSA = New->getAttr<CodeSegAttr>();
-  if ((NewCSA || OldCSA) &&
-      (!OldCSA || !NewCSA || NewCSA->getName() != OldCSA->getName())) {
-    Diag(New->getLocation(), diag::err_mismatched_code_seg_override);
-    Diag(Old->getLocation(), diag::note_previous_declaration);
-    return true;
-  }
-
-  CallingConv NewCC = NewFT->getCallConv(), OldCC = OldFT->getCallConv();
-
-  // If the calling conventions match, everything is fine
-  if (NewCC == OldCC)
-    return false;
-
-  // If the calling conventions mismatch because the new function is static,
-  // suppress the calling convention mismatch error; the error about static
-  // function override (err_static_overrides_virtual from
-  // Sema::CheckFunctionDeclaration) is more clear.
-  if (New->getStorageClass() == SC_Static)
-    return false;
-
-  Diag(New->getLocation(),
-       diag::err_conflicting_overriding_cc_attributes)
-    << New->getDeclName() << New->getType() << Old->getType();
-  Diag(Old->getLocation(), diag::note_overridden_virtual_function);
-  return true;
-}
-
-bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
-                                             const CXXMethodDecl *Old) {
-  QualType NewTy = New->getType()->getAs<FunctionType>()->getReturnType();
-  QualType OldTy = Old->getType()->getAs<FunctionType>()->getReturnType();
-
-  if (Context.hasSameType(NewTy, OldTy) ||
-      NewTy->isDependentType() || OldTy->isDependentType())
-    return false;
-
-  // Check if the return types are covariant
-  QualType NewClassTy, OldClassTy;
-
-  /// Both types must be pointers or references to classes.
-  if (const PointerType *NewPT = NewTy->getAs<PointerType>()) {
-    if (const PointerType *OldPT = OldTy->getAs<PointerType>()) {
-      NewClassTy = NewPT->getPointeeType();
-      OldClassTy = OldPT->getPointeeType();
-    }
-  } else if (const ReferenceType *NewRT = NewTy->getAs<ReferenceType>()) {
-    if (const ReferenceType *OldRT = OldTy->getAs<ReferenceType>()) {
-      if (NewRT->getTypeClass() == OldRT->getTypeClass()) {
-        NewClassTy = NewRT->getPointeeType();
-        OldClassTy = OldRT->getPointeeType();
-      }
-    }
-  }
-
-  // The return types aren't either both pointers or references to a class type.
-  if (NewClassTy.isNull()) {
-    Diag(New->getLocation(),
-         diag::err_different_return_type_for_overriding_virtual_function)
-        << New->getDeclName() << NewTy << OldTy
-        << New->getReturnTypeSourceRange();
-    Diag(Old->getLocation(), diag::note_overridden_virtual_function)
-        << Old->getReturnTypeSourceRange();
-
-    return true;
-  }
-
-  if (!Context.hasSameUnqualifiedType(NewClassTy, OldClassTy)) {
-    // C++14 [class.virtual]p8:
-    //   If the class type in the covariant return type of D::f differs from
-    //   that of B::f, the class type in the return type of D::f shall be
-    //   complete at the point of declaration of D::f or shall be the class
-    //   type D.
-    if (const RecordType *RT = NewClassTy->getAs<RecordType>()) {
-      if (!RT->isBeingDefined() &&
-          RequireCompleteType(New->getLocation(), NewClassTy,
-                              diag::err_covariant_return_incomplete,
-                              New->getDeclName()))
-        return true;
-    }
-
-    // Check if the new class derives from the old class.
-    if (!IsDerivedFrom(New->getLocation(), NewClassTy, OldClassTy)) {
-      Diag(New->getLocation(), diag::err_covariant_return_not_derived)
-          << New->getDeclName() << NewTy << OldTy
-          << New->getReturnTypeSourceRange();
-      Diag(Old->getLocation(), diag::note_overridden_virtual_function)
-          << Old->getReturnTypeSourceRange();
-      return true;
-    }
-
-    // Check if we the conversion from derived to base is valid.
-    if (CheckDerivedToBaseConversion(
-            NewClassTy, OldClassTy,
-            diag::err_covariant_return_inaccessible_base,
-            diag::err_covariant_return_ambiguous_derived_to_base_conv,
-            New->getLocation(), New->getReturnTypeSourceRange(),
-            New->getDeclName(), nullptr)) {
-      // FIXME: this note won't trigger for delayed access control
-      // diagnostics, and it's impossible to get an undelayed error
-      // here from access control during the original parse because
-      // the ParsingDeclSpec/ParsingDeclarator are still in scope.
-      Diag(Old->getLocation(), diag::note_overridden_virtual_function)
-          << Old->getReturnTypeSourceRange();
-      return true;
-    }
-  }
-
-  // The qualifiers of the return types must be the same.
-  if (NewTy.getLocalCVRQualifiers() != OldTy.getLocalCVRQualifiers()) {
-    Diag(New->getLocation(),
-         diag::err_covariant_return_type_different_qualifications)
-        << New->getDeclName() << NewTy << OldTy
-        << New->getReturnTypeSourceRange();
-    Diag(Old->getLocation(), diag::note_overridden_virtual_function)
-        << Old->getReturnTypeSourceRange();
-    return true;
-  }
-
-
-  // The new class type must have the same or less qualifiers as the old type.
-  if (NewClassTy.isMoreQualifiedThan(OldClassTy)) {
-    Diag(New->getLocation(),
-         diag::err_covariant_return_type_class_type_more_qualified)
-        << New->getDeclName() << NewTy << OldTy
-        << New->getReturnTypeSourceRange();
-    Diag(Old->getLocation(), diag::note_overridden_virtual_function)
-        << Old->getReturnTypeSourceRange();
-    return true;
-  }
-
-  return false;
-}
-
-/// Mark the given method pure.
-///
-/// \param Method the method to be marked pure.
-///
-/// \param InitRange the source range that covers the "0" initializer.
-bool Sema::CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange) {
-  SourceLocation EndLoc = InitRange.getEnd();
-  if (EndLoc.isValid())
-    Method->setRangeEnd(EndLoc);
-
-  if (Method->isVirtual() || Method->getParent()->isDependentContext()) {
-    Method->setPure();
-    return false;
-  }
-
-  if (!Method->isInvalidDecl())
-    Diag(Method->getLocation(), diag::err_non_virtual_pure)
-      << Method->getDeclName() << InitRange;
-  return true;
-}
-
-void Sema::ActOnPureSpecifier(Decl *D, SourceLocation ZeroLoc) {
-  if (D->getFriendObjectKind())
-    Diag(D->getLocation(), diag::err_pure_friend);
-  else if (auto *M = dyn_cast<CXXMethodDecl>(D))
-    CheckPureMethod(M, ZeroLoc);
-  else
-    Diag(D->getLocation(), diag::err_illegal_initializer);
-}
-
-/// Determine whether the given declaration is a global variable or
-/// static data member.
-static bool isNonlocalVariable(const Decl *D) {
-  if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(D))
-    return Var->hasGlobalStorage();
-
-  return false;
-}
-
-/// Invoked when we are about to parse an initializer for the declaration
-/// 'Dcl'.
-///
-/// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
-/// static data member of class X, names should be looked up in the scope of
-/// class X. If the declaration had a scope specifier, a scope will have
-/// been created and passed in for this purpose. Otherwise, S will be null.
-void Sema::ActOnCXXEnterDeclInitializer(Scope *S, Decl *D) {
-  // If there is no declaration, there was an error parsing it.
-  if (!D || D->isInvalidDecl())
-    return;
-
-  // We will always have a nested name specifier here, but this declaration
-  // might not be out of line if the specifier names the current namespace:
-  //   extern int n;
-  //   int ::n = 0;
-  if (S && D->isOutOfLine())
-    EnterDeclaratorContext(S, D->getDeclContext());
-
-  // If we are parsing the initializer for a static data member, push a
-  // new expression evaluation context that is associated with this static
-  // data member.
-  if (isNonlocalVariable(D))
-    PushExpressionEvaluationContext(
-        ExpressionEvaluationContext::PotentiallyEvaluated, D);
-}
-
-/// Invoked after we are finished parsing an initializer for the declaration D.
-void Sema::ActOnCXXExitDeclInitializer(Scope *S, Decl *D) {
-  // If there is no declaration, there was an error parsing it.
-  if (!D || D->isInvalidDecl())
-    return;
-
-  if (isNonlocalVariable(D))
-    PopExpressionEvaluationContext();
-
-  if (S && D->isOutOfLine())
-    ExitDeclaratorContext(S);
-}
-
-/// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
-/// C++ if/switch/while/for statement.
-/// e.g: "if (int x = f()) {...}"
-DeclResult Sema::ActOnCXXConditionDeclaration(Scope *S, Declarator &D) {
-  // C++ 6.4p2:
-  // The declarator shall not specify a function or an array.
-  // The type-specifier-seq shall not contain typedef and shall not declare a
-  // new class or enumeration.
-  assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
-         "Parser allowed 'typedef' as storage class of condition decl.");
-
-  Decl *Dcl = ActOnDeclarator(S, D);
-  if (!Dcl)
-    return true;
-
-  if (isa<FunctionDecl>(Dcl)) { // The declarator shall not specify a function.
-    Diag(Dcl->getLocation(), diag::err_invalid_use_of_function_type)
-      << D.getSourceRange();
-    return true;
-  }
-
-  return Dcl;
-}
-
-void Sema::LoadExternalVTableUses() {
-  if (!ExternalSource)
-    return;
-
-  SmallVector<ExternalVTableUse, 4> VTables;
-  ExternalSource->ReadUsedVTables(VTables);
-  SmallVector<VTableUse, 4> NewUses;
-  for (unsigned I = 0, N = VTables.size(); I != N; ++I) {
-    llvm::DenseMap<CXXRecordDecl *, bool>::iterator Pos
-      = VTablesUsed.find(VTables[I].Record);
-    // Even if a definition wasn't required before, it may be required now.
-    if (Pos != VTablesUsed.end()) {
-      if (!Pos->second && VTables[I].DefinitionRequired)
-        Pos->second = true;
-      continue;
-    }
-
-    VTablesUsed[VTables[I].Record] = VTables[I].DefinitionRequired;
-    NewUses.push_back(VTableUse(VTables[I].Record, VTables[I].Location));
-  }
-
-  VTableUses.insert(VTableUses.begin(), NewUses.begin(), NewUses.end());
-}
-
-void Sema::MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
-                          bool DefinitionRequired) {
-  // Ignore any vtable uses in unevaluated operands or for classes that do
-  // not have a vtable.
-  if (!Class->isDynamicClass() || Class->isDependentContext() ||
-      CurContext->isDependentContext() || isUnevaluatedContext())
-    return;
-  // Do not mark as used if compiling for the device outside of the target
-  // region.
-  if (LangOpts.OpenMP && LangOpts.OpenMPIsDevice &&
-      !isInOpenMPDeclareTargetContext() &&
-      !isInOpenMPTargetExecutionDirective()) {
-    if (!DefinitionRequired)
-      MarkVirtualMembersReferenced(Loc, Class);
-    return;
-  }
-
-  // Try to insert this class into the map.
-  LoadExternalVTableUses();
-  Class = Class->getCanonicalDecl();
-  std::pair<llvm::DenseMap<CXXRecordDecl *, bool>::iterator, bool>
-    Pos = VTablesUsed.insert(std::make_pair(Class, DefinitionRequired));
-  if (!Pos.second) {
-    // If we already had an entry, check to see if we are promoting this vtable
-    // to require a definition. If so, we need to reappend to the VTableUses
-    // list, since we may have already processed the first entry.
-    if (DefinitionRequired && !Pos.first->second) {
-      Pos.first->second = true;
-    } else {
-      // Otherwise, we can early exit.
-      return;
-    }
-  } else {
-    // The Microsoft ABI requires that we perform the destructor body
-    // checks (i.e. operator delete() lookup) when the vtable is marked used, as
-    // the deleting destructor is emitted with the vtable, not with the
-    // destructor definition as in the Itanium ABI.
-    if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
-      CXXDestructorDecl *DD = Class->getDestructor();
-      if (DD && DD->isVirtual() && !DD->isDeleted()) {
-        if (Class->hasUserDeclaredDestructor() && !DD->isDefined()) {
-          // If this is an out-of-line declaration, marking it referenced will
-          // not do anything. Manually call CheckDestructor to look up operator
-          // delete().
-          ContextRAII SavedContext(*this, DD);
-          CheckDestructor(DD);
-        } else {
-          MarkFunctionReferenced(Loc, Class->getDestructor());
-        }
-      }
-    }
-  }
-
-  // Local classes need to have their virtual members marked
-  // immediately. For all other classes, we mark their virtual members
-  // at the end of the translation unit.
-  if (Class->isLocalClass())
-    MarkVirtualMembersReferenced(Loc, Class);
-  else
-    VTableUses.push_back(std::make_pair(Class, Loc));
-}
-
-bool Sema::DefineUsedVTables() {
-  LoadExternalVTableUses();
-  if (VTableUses.empty())
-    return false;
-
-  // Note: The VTableUses vector could grow as a result of marking
-  // the members of a class as "used", so we check the size each
-  // time through the loop and prefer indices (which are stable) to
-  // iterators (which are not).
-  bool DefinedAnything = false;
-  for (unsigned I = 0; I != VTableUses.size(); ++I) {
-    CXXRecordDecl *Class = VTableUses[I].first->getDefinition();
-    if (!Class)
-      continue;
-    TemplateSpecializationKind ClassTSK =
-        Class->getTemplateSpecializationKind();
-
-    SourceLocation Loc = VTableUses[I].second;
-
-    bool DefineVTable = true;
-
-    // If this class has a key function, but that key function is
-    // defined in another translation unit, we don't need to emit the
-    // vtable even though we're using it.
-    const CXXMethodDecl *KeyFunction = Context.getCurrentKeyFunction(Class);
-    if (KeyFunction && !KeyFunction->hasBody()) {
-      // The key function is in another translation unit.
-      DefineVTable = false;
-      TemplateSpecializationKind TSK =
-          KeyFunction->getTemplateSpecializationKind();
-      assert(TSK != TSK_ExplicitInstantiationDefinition &&
-             TSK != TSK_ImplicitInstantiation &&
-             "Instantiations don't have key functions");
-      (void)TSK;
-    } else if (!KeyFunction) {
-      // If we have a class with no key function that is the subject
-      // of an explicit instantiation declaration, suppress the
-      // vtable; it will live with the explicit instantiation
-      // definition.
-      bool IsExplicitInstantiationDeclaration =
-          ClassTSK == TSK_ExplicitInstantiationDeclaration;
-      for (auto R : Class->redecls()) {
-        TemplateSpecializationKind TSK
-          = cast<CXXRecordDecl>(R)->getTemplateSpecializationKind();
-        if (TSK == TSK_ExplicitInstantiationDeclaration)
-          IsExplicitInstantiationDeclaration = true;
-        else if (TSK == TSK_ExplicitInstantiationDefinition) {
-          IsExplicitInstantiationDeclaration = false;
-          break;
-        }
-      }
-
-      if (IsExplicitInstantiationDeclaration)
-        DefineVTable = false;
-    }
-
-    // The exception specifications for all virtual members may be needed even
-    // if we are not providing an authoritative form of the vtable in this TU.
-    // We may choose to emit it available_externally anyway.
-    if (!DefineVTable) {
-      MarkVirtualMemberExceptionSpecsNeeded(Loc, Class);
-      continue;
-    }
-
-    // Mark all of the virtual members of this class as referenced, so
-    // that we can build a vtable. Then, tell the AST consumer that a
-    // vtable for this class is required.
-    DefinedAnything = true;
-    MarkVirtualMembersReferenced(Loc, Class);
-    CXXRecordDecl *Canonical = Class->getCanonicalDecl();
-    if (VTablesUsed[Canonical])
-      Consumer.HandleVTable(Class);
-
-    // Warn if we're emitting a weak vtable. The vtable will be weak if there is
-    // no key function or the key function is inlined. Don't warn in C++ ABIs
-    // that lack key functions, since the user won't be able to make one.
-    if (Context.getTargetInfo().getCXXABI().hasKeyFunctions() &&
-        Class->isExternallyVisible() && ClassTSK != TSK_ImplicitInstantiation) {
-      const FunctionDecl *KeyFunctionDef = nullptr;
-      if (!KeyFunction || (KeyFunction->hasBody(KeyFunctionDef) &&
-                           KeyFunctionDef->isInlined())) {
-        Diag(Class->getLocation(),
-             ClassTSK == TSK_ExplicitInstantiationDefinition
-                 ? diag::warn_weak_template_vtable
-                 : diag::warn_weak_vtable)
-            << Class;
-      }
-    }
-  }
-  VTableUses.clear();
-
-  return DefinedAnything;
-}
-
-void Sema::MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
-                                                 const CXXRecordDecl *RD) {
-  for (const auto *I : RD->methods())
-    if (I->isVirtual() && !I->isPure())
-      ResolveExceptionSpec(Loc, I->getType()->castAs<FunctionProtoType>());
-}
-
-void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
-                                        const CXXRecordDecl *RD) {
-  // Mark all functions which will appear in RD's vtable as used.
-  CXXFinalOverriderMap FinalOverriders;
-  RD->getFinalOverriders(FinalOverriders);
-  for (CXXFinalOverriderMap::const_iterator I = FinalOverriders.begin(),
-                                            E = FinalOverriders.end();
-       I != E; ++I) {
-    for (OverridingMethods::const_iterator OI = I->second.begin(),
-                                           OE = I->second.end();
-         OI != OE; ++OI) {
-      assert(OI->second.size() > 0 && "no final overrider");
-      CXXMethodDecl *Overrider = OI->second.front().Method;
-
-      // C++ [basic.def.odr]p2:
-      //   [...] A virtual member function is used if it is not pure. [...]
-      if (!Overrider->isPure())
-        MarkFunctionReferenced(Loc, Overrider);
-    }
-  }
-
-  // Only classes that have virtual bases need a VTT.
-  if (RD->getNumVBases() == 0)
-    return;
-
-  for (const auto &I : RD->bases()) {
-    const CXXRecordDecl *Base =
-        cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
-    if (Base->getNumVBases() == 0)
-      continue;
-    MarkVirtualMembersReferenced(Loc, Base);
-  }
-}
-
-/// SetIvarInitializers - This routine builds initialization ASTs for the
-/// Objective-C implementation whose ivars need be initialized.
-void Sema::SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation) {
-  if (!getLangOpts().CPlusPlus)
-    return;
-  if (ObjCInterfaceDecl *OID = ObjCImplementation->getClassInterface()) {
-    SmallVector<ObjCIvarDecl*, 8> ivars;
-    CollectIvarsToConstructOrDestruct(OID, ivars);
-    if (ivars.empty())
-      return;
-    SmallVector<CXXCtorInitializer*, 32> AllToInit;
-    for (unsigned i = 0; i < ivars.size(); i++) {
-      FieldDecl *Field = ivars[i];
-      if (Field->isInvalidDecl())
-        continue;
-
-      CXXCtorInitializer *Member;
-      InitializedEntity InitEntity = InitializedEntity::InitializeMember(Field);
-      InitializationKind InitKind =
-        InitializationKind::CreateDefault(ObjCImplementation->getLocation());
-
-      InitializationSequence InitSeq(*this, InitEntity, InitKind, None);
-      ExprResult MemberInit =
-        InitSeq.Perform(*this, InitEntity, InitKind, None);
-      MemberInit = MaybeCreateExprWithCleanups(MemberInit);
-      // Note, MemberInit could actually come back empty if no initialization
-      // is required (e.g., because it would call a trivial default constructor)
-      if (!MemberInit.get() || MemberInit.isInvalid())
-        continue;
-
-      Member =
-        new (Context) CXXCtorInitializer(Context, Field, SourceLocation(),
-                                         SourceLocation(),
-                                         MemberInit.getAs<Expr>(),
-                                         SourceLocation());
-      AllToInit.push_back(Member);
-
-      // Be sure that the destructor is accessible and is marked as referenced.
-      if (const RecordType *RecordTy =
-              Context.getBaseElementType(Field->getType())
-                  ->getAs<RecordType>()) {
-        CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
-        if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
-          MarkFunctionReferenced(Field->getLocation(), Destructor);
-          CheckDestructorAccess(Field->getLocation(), Destructor,
-                            PDiag(diag::err_access_dtor_ivar)
-                              << Context.getBaseElementType(Field->getType()));
-        }
-      }
-    }
-    ObjCImplementation->setIvarInitializers(Context,
-                                            AllToInit.data(), AllToInit.size());
-  }
-}
-
-static
-void DelegatingCycleHelper(CXXConstructorDecl* Ctor,
-                           llvm::SmallPtrSet<CXXConstructorDecl*, 4> &Valid,
-                           llvm::SmallPtrSet<CXXConstructorDecl*, 4> &Invalid,
-                           llvm::SmallPtrSet<CXXConstructorDecl*, 4> &Current,
-                           Sema &S) {
-  if (Ctor->isInvalidDecl())
-    return;
-
-  CXXConstructorDecl *Target = Ctor->getTargetConstructor();
-
-  // Target may not be determinable yet, for instance if this is a dependent
-  // call in an uninstantiated template.
-  if (Target) {
-    const FunctionDecl *FNTarget = nullptr;
-    (void)Target->hasBody(FNTarget);
-    Target = const_cast<CXXConstructorDecl*>(
-      cast_or_null<CXXConstructorDecl>(FNTarget));
-  }
-
-  CXXConstructorDecl *Canonical = Ctor->getCanonicalDecl(),
-                     // Avoid dereferencing a null pointer here.
-                     *TCanonical = Target? Target->getCanonicalDecl() : nullptr;
-
-  if (!Current.insert(Canonical).second)
-    return;
-
-  // We know that beyond here, we aren't chaining into a cycle.
-  if (!Target || !Target->isDelegatingConstructor() ||
-      Target->isInvalidDecl() || Valid.count(TCanonical)) {
-    Valid.insert(Current.begin(), Current.end());
-    Current.clear();
-  // We've hit a cycle.
-  } else if (TCanonical == Canonical || Invalid.count(TCanonical) ||
-             Current.count(TCanonical)) {
-    // If we haven't diagnosed this cycle yet, do so now.
-    if (!Invalid.count(TCanonical)) {
-      S.Diag((*Ctor->init_begin())->getSourceLocation(),
-             diag::warn_delegating_ctor_cycle)
-        << Ctor;
-
-      // Don't add a note for a function delegating directly to itself.
-      if (TCanonical != Canonical)
-        S.Diag(Target->getLocation(), diag::note_it_delegates_to);
-
-      CXXConstructorDecl *C = Target;
-      while (C->getCanonicalDecl() != Canonical) {
-        const FunctionDecl *FNTarget = nullptr;
-        (void)C->getTargetConstructor()->hasBody(FNTarget);
-        assert(FNTarget && "Ctor cycle through bodiless function");
-
-        C = const_cast<CXXConstructorDecl*>(
-          cast<CXXConstructorDecl>(FNTarget));
-        S.Diag(C->getLocation(), diag::note_which_delegates_to);
-      }
-    }
-
-    Invalid.insert(Current.begin(), Current.end());
-    Current.clear();
-  } else {
-    DelegatingCycleHelper(Target, Valid, Invalid, Current, S);
-  }
-}
-
-
-void Sema::CheckDelegatingCtorCycles() {
-  llvm::SmallPtrSet<CXXConstructorDecl*, 4> Valid, Invalid, Current;
-
-  for (DelegatingCtorDeclsType::iterator
-         I = DelegatingCtorDecls.begin(ExternalSource),
-         E = DelegatingCtorDecls.end();
-       I != E; ++I)
-    DelegatingCycleHelper(*I, Valid, Invalid, Current, *this);
-
-  for (auto CI = Invalid.begin(), CE = Invalid.end(); CI != CE; ++CI)
-    (*CI)->setInvalidDecl();
-}
-
-namespace {
-  /// AST visitor that finds references to the 'this' expression.
-  class FindCXXThisExpr : public RecursiveASTVisitor<FindCXXThisExpr> {
-    Sema &S;
-
-  public:
-    explicit FindCXXThisExpr(Sema &S) : S(S) { }
-
-    bool VisitCXXThisExpr(CXXThisExpr *E) {
-      S.Diag(E->getLocation(), diag::err_this_static_member_func)
-        << E->isImplicit();
-      return false;
-    }
-  };
-}
-
-bool Sema::checkThisInStaticMemberFunctionType(CXXMethodDecl *Method) {
-  TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
-  if (!TSInfo)
-    return false;
-
-  TypeLoc TL = TSInfo->getTypeLoc();
-  FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
-  if (!ProtoTL)
-    return false;
-
-  // C++11 [expr.prim.general]p3:
-  //   [The expression this] shall not appear before the optional
-  //   cv-qualifier-seq and it shall not appear within the declaration of a
-  //   static member function (although its type and value category are defined
-  //   within a static member function as they are within a non-static member
-  //   function). [ Note: this is because declaration matching does not occur
-  //  until the complete declarator is known. - end note ]
-  const FunctionProtoType *Proto = ProtoTL.getTypePtr();
-  FindCXXThisExpr Finder(*this);
-
-  // If the return type came after the cv-qualifier-seq, check it now.
-  if (Proto->hasTrailingReturn() &&
-      !Finder.TraverseTypeLoc(ProtoTL.getReturnLoc()))
-    return true;
-
-  // Check the exception specification.
-  if (checkThisInStaticMemberFunctionExceptionSpec(Method))
-    return true;
-
-  return checkThisInStaticMemberFunctionAttributes(Method);
-}
-
-bool Sema::checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method) {
-  TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
-  if (!TSInfo)
-    return false;
-
-  TypeLoc TL = TSInfo->getTypeLoc();
-  FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
-  if (!ProtoTL)
-    return false;
-
-  const FunctionProtoType *Proto = ProtoTL.getTypePtr();
-  FindCXXThisExpr Finder(*this);
-
-  switch (Proto->getExceptionSpecType()) {
-  case EST_Unparsed:
-  case EST_Uninstantiated:
-  case EST_Unevaluated:
-  case EST_BasicNoexcept:
-  case EST_DynamicNone:
-  case EST_MSAny:
-  case EST_None:
-    break;
-
-  case EST_DependentNoexcept:
-  case EST_NoexceptFalse:
-  case EST_NoexceptTrue:
-    if (!Finder.TraverseStmt(Proto->getNoexceptExpr()))
-      return true;
-    LLVM_FALLTHROUGH;
-
-  case EST_Dynamic:
-    for (const auto &E : Proto->exceptions()) {
-      if (!Finder.TraverseType(E))
-        return true;
-    }
-    break;
-  }
-
-  return false;
-}
-
-bool Sema::checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method) {
-  FindCXXThisExpr Finder(*this);
-
-  // Check attributes.
-  for (const auto *A : Method->attrs()) {
-    // FIXME: This should be emitted by tblgen.
-    Expr *Arg = nullptr;
-    ArrayRef<Expr *> Args;
-    if (const auto *G = dyn_cast<GuardedByAttr>(A))
-      Arg = G->getArg();
-    else if (const auto *G = dyn_cast<PtGuardedByAttr>(A))
-      Arg = G->getArg();
-    else if (const auto *AA = dyn_cast<AcquiredAfterAttr>(A))
-      Args = llvm::makeArrayRef(AA->args_begin(), AA->args_size());
-    else if (const auto *AB = dyn_cast<AcquiredBeforeAttr>(A))
-      Args = llvm::makeArrayRef(AB->args_begin(), AB->args_size());
-    else if (const auto *ETLF = dyn_cast<ExclusiveTrylockFunctionAttr>(A)) {
-      Arg = ETLF->getSuccessValue();
-      Args = llvm::makeArrayRef(ETLF->args_begin(), ETLF->args_size());
-    } else if (const auto *STLF = dyn_cast<SharedTrylockFunctionAttr>(A)) {
-      Arg = STLF->getSuccessValue();
-      Args = llvm::makeArrayRef(STLF->args_begin(), STLF->args_size());
-    } else if (const auto *LR = dyn_cast<LockReturnedAttr>(A))
-      Arg = LR->getArg();
-    else if (const auto *LE = dyn_cast<LocksExcludedAttr>(A))
-      Args = llvm::makeArrayRef(LE->args_begin(), LE->args_size());
-    else if (const auto *RC = dyn_cast<RequiresCapabilityAttr>(A))
-      Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
-    else if (const auto *AC = dyn_cast<AcquireCapabilityAttr>(A))
-      Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
-    else if (const auto *AC = dyn_cast<TryAcquireCapabilityAttr>(A))
-      Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
-    else if (const auto *RC = dyn_cast<ReleaseCapabilityAttr>(A))
-      Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
-
-    if (Arg && !Finder.TraverseStmt(Arg))
-      return true;
-
-    for (unsigned I = 0, N = Args.size(); I != N; ++I) {
-      if (!Finder.TraverseStmt(Args[I]))
-        return true;
-    }
-  }
-
-  return false;
-}
-
-void Sema::checkExceptionSpecification(
-    bool IsTopLevel, ExceptionSpecificationType EST,
-    ArrayRef<ParsedType> DynamicExceptions,
-    ArrayRef<SourceRange> DynamicExceptionRanges, Expr *NoexceptExpr,
-    SmallVectorImpl<QualType> &Exceptions,
-    FunctionProtoType::ExceptionSpecInfo &ESI) {
-  Exceptions.clear();
-  ESI.Type = EST;
-  if (EST == EST_Dynamic) {
-    Exceptions.reserve(DynamicExceptions.size());
-    for (unsigned ei = 0, ee = DynamicExceptions.size(); ei != ee; ++ei) {
-      // FIXME: Preserve type source info.
-      QualType ET = GetTypeFromParser(DynamicExceptions[ei]);
-
-      if (IsTopLevel) {
-        SmallVector<UnexpandedParameterPack, 2> Unexpanded;
-        collectUnexpandedParameterPacks(ET, Unexpanded);
-        if (!Unexpanded.empty()) {
-          DiagnoseUnexpandedParameterPacks(
-              DynamicExceptionRanges[ei].getBegin(), UPPC_ExceptionType,
-              Unexpanded);
-          continue;
-        }
-      }
-
-      // Check that the type is valid for an exception spec, and
-      // drop it if not.
-      if (!CheckSpecifiedExceptionType(ET, DynamicExceptionRanges[ei]))
-        Exceptions.push_back(ET);
-    }
-    ESI.Exceptions = Exceptions;
-    return;
-  }
-
-  if (isComputedNoexcept(EST)) {
-    assert((NoexceptExpr->isTypeDependent() ||
-            NoexceptExpr->getType()->getCanonicalTypeUnqualified() ==
-            Context.BoolTy) &&
-           "Parser should have made sure that the expression is boolean");
-    if (IsTopLevel && DiagnoseUnexpandedParameterPack(NoexceptExpr)) {
-      ESI.Type = EST_BasicNoexcept;
-      return;
-    }
-
-    ESI.NoexceptExpr = NoexceptExpr;
-    return;
-  }
-}
-
-void Sema::actOnDelayedExceptionSpecification(Decl *MethodD,
-             ExceptionSpecificationType EST,
-             SourceRange SpecificationRange,
-             ArrayRef<ParsedType> DynamicExceptions,
-             ArrayRef<SourceRange> DynamicExceptionRanges,
-             Expr *NoexceptExpr) {
-  if (!MethodD)
-    return;
-
-  // Dig out the method we're referring to.
-  if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(MethodD))
-    MethodD = FunTmpl->getTemplatedDecl();
-
-  CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(MethodD);
-  if (!Method)
-    return;
-
-  // Check the exception specification.
-  llvm::SmallVector<QualType, 4> Exceptions;
-  FunctionProtoType::ExceptionSpecInfo ESI;
-  checkExceptionSpecification(/*IsTopLevel*/true, EST, DynamicExceptions,
-                              DynamicExceptionRanges, NoexceptExpr, Exceptions,
-                              ESI);
-
-  // Update the exception specification on the function type.
-  Context.adjustExceptionSpec(Method, ESI, /*AsWritten*/true);
-
-  if (Method->isStatic())
-    checkThisInStaticMemberFunctionExceptionSpec(Method);
-
-  if (Method->isVirtual()) {
-    // Check overrides, which we previously had to delay.
-    for (const CXXMethodDecl *O : Method->overridden_methods())
-      CheckOverridingFunctionExceptionSpec(Method, O);
-  }
-}
-
-/// HandleMSProperty - Analyze a __delcspec(property) field of a C++ class.
-///
-MSPropertyDecl *Sema::HandleMSProperty(Scope *S, RecordDecl *Record,
-                                       SourceLocation DeclStart, Declarator &D,
-                                       Expr *BitWidth,
-                                       InClassInitStyle InitStyle,
-                                       AccessSpecifier AS,
-                                       const ParsedAttr &MSPropertyAttr) {
-  IdentifierInfo *II = D.getIdentifier();
-  if (!II) {
-    Diag(DeclStart, diag::err_anonymous_property);
-    return nullptr;
-  }
-  SourceLocation Loc = D.getIdentifierLoc();
-
-  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
-  QualType T = TInfo->getType();
-  if (getLangOpts().CPlusPlus) {
-    CheckExtraCXXDefaultArguments(D);
-
-    if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
-                                        UPPC_DataMemberType)) {
-      D.setInvalidType();
-      T = Context.IntTy;
-      TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
-    }
-  }
-
-  DiagnoseFunctionSpecifiers(D.getDeclSpec());
-
-  if (D.getDeclSpec().isInlineSpecified())
-    Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
-        << getLangOpts().CPlusPlus17;
-  if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
-    Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
-         diag::err_invalid_thread)
-      << DeclSpec::getSpecifierName(TSCS);
-
-  // Check to see if this name was declared as a member previously
-  NamedDecl *PrevDecl = nullptr;
-  LookupResult Previous(*this, II, Loc, LookupMemberName,
-                        ForVisibleRedeclaration);
-  LookupName(Previous, S);
-  switch (Previous.getResultKind()) {
-  case LookupResult::Found:
-  case LookupResult::FoundUnresolvedValue:
-    PrevDecl = Previous.getAsSingle<NamedDecl>();
-    break;
-
-  case LookupResult::FoundOverloaded:
-    PrevDecl = Previous.getRepresentativeDecl();
-    break;
-
-  case LookupResult::NotFound:
-  case LookupResult::NotFoundInCurrentInstantiation:
-  case LookupResult::Ambiguous:
-    break;
-  }
-
-  if (PrevDecl && PrevDecl->isTemplateParameter()) {
-    // Maybe we will complain about the shadowed template parameter.
-    DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
-    // Just pretend that we didn't see the previous declaration.
-    PrevDecl = nullptr;
-  }
-
-  if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
-    PrevDecl = nullptr;
-
-  SourceLocation TSSL = D.getBeginLoc();
-  MSPropertyDecl *NewPD =
-      MSPropertyDecl::Create(Context, Record, Loc, II, T, TInfo, TSSL,
-                             MSPropertyAttr.getPropertyDataGetter(),
-                             MSPropertyAttr.getPropertyDataSetter());
-  ProcessDeclAttributes(TUScope, NewPD, D);
-  NewPD->setAccess(AS);
-
-  if (NewPD->isInvalidDecl())
-    Record->setInvalidDecl();
-
-  if (D.getDeclSpec().isModulePrivateSpecified())
-    NewPD->setModulePrivate();
-
-  if (NewPD->isInvalidDecl() && PrevDecl) {
-    // Don't introduce NewFD into scope; there's already something
-    // with the same name in the same scope.
-  } else if (II) {
-    PushOnScopeChains(NewPD, S);
-  } else
-    Record->addDecl(NewPD);
-
-  return NewPD;
-}