Merge libc++, libc++abi and libunwind version 7.0.1.

Tested by visa on octeon
Tested by kettenis on arm64, armv7 and sparc64
"go for it" deraadt and sthen

4 files changed, 0 insertions, 1771 deletions

diff --git a/lib/libcxx/src/experimental/filesystem/directory_iterator.cpp b/lib/libcxx/src/experimental/filesystem/directory_iterator.cpp
deleted file mode 100644
index a552fdc4461..00000000000
--- a/lib/libcxx/src/experimental/filesystem/directory_iterator.cpp
+++ /dev/null
@@ -1,342 +0,0 @@
-//===------------------ directory_iterator.cpp ----------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "experimental/filesystem"
-#include "__config"
-#if defined(_LIBCPP_WIN32API)
-#define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
-#else
-#include <dirent.h>
-#endif
-#include <errno.h>
-
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-namespace { namespace detail {
-
-#if !defined(_LIBCPP_WIN32API)
-inline error_code capture_errno() {
-    _LIBCPP_ASSERT(errno, "Expected errno to be non-zero");
-    return error_code{errno, std::generic_category()};
-}
-#endif
-
-template <class ...Args>
-inline bool set_or_throw(std::error_code& my_ec,
-                               std::error_code* user_ec,
-                               const char* msg, Args&&... args)
-{
-    if (user_ec) {
-        *user_ec = my_ec;
-        return true;
-    }
-    __throw_filesystem_error(msg, std::forward<Args>(args)..., my_ec);
-    return false;
-}
-
-#if !defined(_LIBCPP_WIN32API)
-inline path::string_type posix_readdir(DIR *dir_stream, error_code& ec) {
-    struct dirent* dir_entry_ptr = nullptr;
-    errno = 0; // zero errno in order to detect errors
-    ec.clear();
-    if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) {
-        if (errno)
-          ec = capture_errno();
-        return {};
-    } else {
-        return dir_entry_ptr->d_name;
-    }
-}
-#endif
-
-}}                                                       // namespace detail
-
-using detail::set_or_throw;
-
-#if defined(_LIBCPP_WIN32API)
-class __dir_stream {
-public:
-  __dir_stream() = delete;
-  __dir_stream& operator=(const __dir_stream&) = delete;
-
-  __dir_stream(__dir_stream&& __ds) noexcept
-      : __stream_(__ds.__stream_), __root_(std::move(__ds.__root_)),
-        __entry_(std::move(__ds.__entry_)) {
-    __ds.__stream_ = INVALID_HANDLE_VALUE;
-  }
-
-  __dir_stream(const path& root, directory_options opts, error_code& ec)
-      : __stream_(INVALID_HANDLE_VALUE), __root_(root) {
-    __stream_ = ::FindFirstFile(root.c_str(), &__data_);
-    if (__stream_ == INVALID_HANDLE_VALUE) {
-      ec = error_code(::GetLastError(), std::generic_category());
-      const bool ignore_permission_denied =
-          bool(opts & directory_options::skip_permission_denied);
-      if (ignore_permission_denied && ec.value() == ERROR_ACCESS_DENIED)
-        ec.clear();
-      return;
-    }
-  }
-
-  ~__dir_stream() noexcept {
-    if (__stream_ == INVALID_HANDLE_VALUE)
-      return;
-    close();
-  }
-
-  bool good() const noexcept { return __stream_ != INVALID_HANDLE_VALUE; }
-
-  bool advance(error_code& ec) {
-    while (::FindNextFile(__stream_, &__data_)) {
-      if (!strcmp(__data_.cFileName, ".") || strcmp(__data_.cFileName, ".."))
-        continue;
-      __entry_.assign(__root_ / __data_.cFileName);
-      return true;
-    }
-    ec = error_code(::GetLastError(), std::generic_category());
-    close();
-    return false;
-  }
-
-private:
-  std::error_code close() noexcept {
-    std::error_code ec;
-    if (!::FindClose(__stream_))
-      ec = error_code(::GetLastError(), std::generic_category());
-    __stream_ = INVALID_HANDLE_VALUE;
-    return ec;
-  }
-
-  HANDLE __stream_{INVALID_HANDLE_VALUE};
-  WIN32_FIND_DATA __data_;
-
-public:
-  path __root_;
-  directory_entry __entry_;
-};
-#else
-class __dir_stream {
-public:
-    __dir_stream() = delete;
-    __dir_stream& operator=(const __dir_stream&) = delete;
-
-    __dir_stream(__dir_stream&& other) noexcept
-        : __stream_(other.__stream_), __root_(std::move(other.__root_)),
-          __entry_(std::move(other.__entry_))
-    {
-        other.__stream_ = nullptr;
-    }
-
-
-    __dir_stream(const path& root, directory_options opts, error_code& ec)
-        : __stream_(nullptr),
-          __root_(root)
-    {
-        if ((__stream_ = ::opendir(root.c_str())) == nullptr) {
-            ec = detail::capture_errno();
-            const bool allow_eacess =
-                bool(opts & directory_options::skip_permission_denied);
-            if (allow_eacess && ec.value() == EACCES)
-                ec.clear();
-            return;
-        }
-        advance(ec);
-    }
-
-    ~__dir_stream() noexcept
-      { if (__stream_) close(); }
-
-    bool good() const noexcept { return __stream_ != nullptr; }
-
-    bool advance(error_code &ec) {
-        while (true) {
-            auto str = detail::posix_readdir(__stream_,  ec);
-            if (str == "." || str == "..") {
-                continue;
-            } else if (ec || str.empty()) {
-                close();
-                return false;
-            } else {
-                __entry_.assign(__root_ / str);
-                return true;
-            }
-        }
-    }
-private:
-    std::error_code close() noexcept {
-        std::error_code m_ec;
-        if (::closedir(__stream_) == -1)
-           m_ec = detail::capture_errno();
-        __stream_ = nullptr;
-        return m_ec;
-    }
-
-    DIR * __stream_{nullptr};
-public:
-    path __root_;
-    directory_entry __entry_;
-};
-#endif
-
-// directory_iterator
-
-directory_iterator::directory_iterator(const path& p, error_code *ec,
-                                       directory_options opts)
-{
-    std::error_code m_ec;
-    __imp_ = make_shared<__dir_stream>(p, opts, m_ec);
-    if (ec) *ec = m_ec;
-    if (!__imp_->good()) {
-        __imp_.reset();
-        if (m_ec)
-            set_or_throw(m_ec, ec,
-                         "directory_iterator::directory_iterator(...)", p);
-    }
-}
-
-directory_iterator& directory_iterator::__increment(error_code *ec)
-{
-    _LIBCPP_ASSERT(__imp_, "Attempting to increment an invalid iterator");
-    std::error_code m_ec;
-    if (!__imp_->advance(m_ec)) {
-        __imp_.reset();
-        if (m_ec)
-            set_or_throw(m_ec, ec, "directory_iterator::operator++()");
-    } else {
-        if (ec) ec->clear();
-    }
-    return *this;
-
-}
-
-directory_entry const& directory_iterator::__dereference() const {
-    _LIBCPP_ASSERT(__imp_, "Attempting to dereference an invalid iterator");
-    return __imp_->__entry_;
-}
-
-// recursive_directory_iterator
-
-struct recursive_directory_iterator::__shared_imp {
-  stack<__dir_stream> __stack_;
-  directory_options   __options_;
-};
-
-recursive_directory_iterator::recursive_directory_iterator(const path& p,
-    directory_options opt, error_code *ec)
-    : __imp_(nullptr), __rec_(true)
-{
-    if (ec) ec->clear();
-    std::error_code m_ec;
-    __dir_stream new_s(p, opt, m_ec);
-    if (m_ec) set_or_throw(m_ec, ec, "recursive_directory_iterator", p);
-    if (m_ec || !new_s.good()) return;
-
-    __imp_ = _VSTD::make_shared<__shared_imp>();
-    __imp_->__options_ = opt;
-    __imp_->__stack_.push(_VSTD::move(new_s));
-}
-
-void recursive_directory_iterator::__pop(error_code* ec)
-{
-    _LIBCPP_ASSERT(__imp_, "Popping the end iterator");
-    if (ec) ec->clear();
-    __imp_->__stack_.pop();
-    if (__imp_->__stack_.size() == 0)
-        __imp_.reset();
-    else
-        __advance(ec);
-}
-
-directory_options recursive_directory_iterator::options() const {
-    return __imp_->__options_;
-}
-
-int recursive_directory_iterator::depth() const {
-    return __imp_->__stack_.size() - 1;
-}
-
-const directory_entry& recursive_directory_iterator::__dereference() const {
-    return __imp_->__stack_.top().__entry_;
-}
-
-recursive_directory_iterator&
-recursive_directory_iterator::__increment(error_code *ec)
-{
-    if (ec) ec->clear();
-    if (recursion_pending()) {
-        if (__try_recursion(ec) || (ec && *ec))
-            return *this;
-    }
-    __rec_ = true;
-    __advance(ec);
-    return *this;
-}
-
-void recursive_directory_iterator::__advance(error_code* ec) {
-    // REQUIRES: ec must be cleared before calling this function.
-    const directory_iterator end_it;
-    auto& stack = __imp_->__stack_;
-    std::error_code m_ec;
-    while (stack.size() > 0) {
-        if (stack.top().advance(m_ec))
-            return;
-        if (m_ec) break;
-        stack.pop();
-    }
-    __imp_.reset();
-    if (m_ec)
-        set_or_throw(m_ec, ec, "recursive_directory_iterator::operator++()");
-}
-
-bool recursive_directory_iterator::__try_recursion(error_code *ec) {
-    bool rec_sym =
-        bool(options() & directory_options::follow_directory_symlink);
-
-    auto& curr_it = __imp_->__stack_.top();
-
-    bool skip_rec = false;
-    std::error_code m_ec;
-    if (!rec_sym) {
-      file_status st = curr_it.__entry_.symlink_status(m_ec);
-      if (m_ec && status_known(st))
-        m_ec.clear();
-      if (m_ec || is_symlink(st) || !is_directory(st))
-        skip_rec = true;
-    } else {
-      file_status st = curr_it.__entry_.status(m_ec);
-      if (m_ec && status_known(st))
-        m_ec.clear();
-      if (m_ec || !is_directory(st))
-        skip_rec = true;
-    }
-
-    if (!skip_rec) {
-        __dir_stream new_it(curr_it.__entry_.path(), __imp_->__options_, m_ec);
-        if (new_it.good()) {
-            __imp_->__stack_.push(_VSTD::move(new_it));
-            return true;
-        }
-    }
-    if (m_ec) {
-        const bool allow_eacess = bool(__imp_->__options_
-            & directory_options::skip_permission_denied);
-        if (m_ec.value() == EACCES && allow_eacess) {
-          if (ec) ec->clear();
-        } else {
-          __imp_.reset();
-          set_or_throw(m_ec, ec,
-                       "recursive_directory_iterator::operator++()");
-        }
-    }
-    return false;
-}
-
-
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
diff --git a/lib/libcxx/src/experimental/filesystem/filesystem_time_helper.h b/lib/libcxx/src/experimental/filesystem/filesystem_time_helper.h
deleted file mode 100644
index a60fdef5f0d..00000000000
--- a/lib/libcxx/src/experimental/filesystem/filesystem_time_helper.h
+++ /dev/null
@@ -1,173 +0,0 @@
-//===----------------------------------------------------------------------===////
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===////
-
-#ifndef FILESYSTEM_TIME_HELPER_H
-#define FILESYSTEM_TIME_HELPER_H
-
-#include "experimental/__config"
-#include "chrono"
-#include "cstdlib"
-#include "climits"
-
-#include <unistd.h>
-#include <sys/stat.h>
-#if !defined(UTIME_OMIT)
-#include <sys/time.h> // for ::utimes as used in __last_write_time
-#endif
-
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-namespace time_detail { namespace {
-
-using namespace chrono;
-
-template <class FileTimeT,
-          bool IsFloat = is_floating_point<typename FileTimeT::rep>::value>
-struct fs_time_util_base {
-  static constexpr auto max_seconds =
-      duration_cast<seconds>(FileTimeT::duration::max()).count();
-
-  static constexpr auto max_nsec =
-      duration_cast<nanoseconds>(FileTimeT::duration::max() -
-                                 seconds(max_seconds))
-          .count();
-
-  static constexpr auto min_seconds =
-      duration_cast<seconds>(FileTimeT::duration::min()).count();
-
-  static constexpr auto min_nsec_timespec =
-      duration_cast<nanoseconds>(
-          (FileTimeT::duration::min() - seconds(min_seconds)) + seconds(1))
-          .count();
-
-  // Static assert that these values properly round trip.
-  static_assert((seconds(min_seconds) +
-                 duration_cast<microseconds>(nanoseconds(min_nsec_timespec))) -
-                        duration_cast<microseconds>(seconds(1)) ==
-                    FileTimeT::duration::min(),
-                "");
-};
-
-template <class FileTimeT>
-struct fs_time_util_base<FileTimeT, true> {
-  static const long long max_seconds;
-  static const long long max_nsec;
-  static const long long min_seconds;
-  static const long long min_nsec_timespec;
-};
-
-template <class FileTimeT>
-const long long fs_time_util_base<FileTimeT, true>::max_seconds =
-    duration_cast<seconds>(FileTimeT::duration::max()).count();
-
-template <class FileTimeT>
-const long long fs_time_util_base<FileTimeT, true>::max_nsec =
-    duration_cast<nanoseconds>(FileTimeT::duration::max() -
-                               seconds(max_seconds))
-        .count();
-
-template <class FileTimeT>
-const long long fs_time_util_base<FileTimeT, true>::min_seconds =
-    duration_cast<seconds>(FileTimeT::duration::min()).count();
-
-template <class FileTimeT>
-const long long fs_time_util_base<FileTimeT, true>::min_nsec_timespec =
-    duration_cast<nanoseconds>((FileTimeT::duration::min() -
-                                seconds(min_seconds)) +
-                               seconds(1))
-        .count();
-
-template <class FileTimeT, class TimeT, class TimeSpecT>
-struct fs_time_util : fs_time_util_base<FileTimeT> {
-  using Base = fs_time_util_base<FileTimeT>;
-  using Base::max_nsec;
-  using Base::max_seconds;
-  using Base::min_nsec_timespec;
-  using Base::min_seconds;
-
-public:
-  template <class CType, class ChronoType>
-  static bool checked_set(CType* out, ChronoType time) {
-    using Lim = numeric_limits<CType>;
-    if (time > Lim::max() || time < Lim::min())
-      return false;
-    *out = static_cast<CType>(time);
-    return true;
-  }
-
-  static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool is_representable(TimeSpecT tm) {
-    if (tm.tv_sec >= 0) {
-      return (tm.tv_sec < max_seconds) ||
-             (tm.tv_sec == max_seconds && tm.tv_nsec <= max_nsec);
-    } else if (tm.tv_sec == (min_seconds - 1)) {
-      return tm.tv_nsec >= min_nsec_timespec;
-    } else {
-      return (tm.tv_sec >= min_seconds);
-    }
-  }
-
-  static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool is_representable(FileTimeT tm) {
-    auto secs = duration_cast<seconds>(tm.time_since_epoch());
-    auto nsecs = duration_cast<nanoseconds>(tm.time_since_epoch() - secs);
-    if (nsecs.count() < 0) {
-      secs = secs + seconds(1);
-      nsecs = nsecs + seconds(1);
-    }
-    using TLim = numeric_limits<TimeT>;
-    if (secs.count() >= 0)
-      return secs.count() <= TLim::max();
-    return secs.count() >= TLim::min();
-  }
-
-  static _LIBCPP_CONSTEXPR_AFTER_CXX11 FileTimeT
-  convert_timespec(TimeSpecT tm) {
-    auto adj_msec = duration_cast<microseconds>(nanoseconds(tm.tv_nsec));
-    if (tm.tv_sec >= 0) {
-      auto Dur = seconds(tm.tv_sec) + microseconds(adj_msec);
-      return FileTimeT(Dur);
-    } else if (duration_cast<microseconds>(nanoseconds(tm.tv_nsec)).count() ==
-               0) {
-      return FileTimeT(seconds(tm.tv_sec));
-    } else { // tm.tv_sec < 0
-      auto adj_subsec =
-          duration_cast<microseconds>(seconds(1) - nanoseconds(tm.tv_nsec));
-      auto Dur = seconds(tm.tv_sec + 1) - adj_subsec;
-      return FileTimeT(Dur);
-    }
-  }
-
-  template <class SubSecDurT, class SubSecT>
-  static bool set_times_checked(TimeT* sec_out, SubSecT* subsec_out,
-                                FileTimeT tp) {
-    using namespace chrono;
-    auto dur = tp.time_since_epoch();
-    auto sec_dur = duration_cast<seconds>(dur);
-    auto subsec_dur = duration_cast<SubSecDurT>(dur - sec_dur);
-    // The tv_nsec and tv_usec fields must not be negative so adjust accordingly
-    if (subsec_dur.count() < 0) {
-      if (sec_dur.count() > min_seconds) {
-        sec_dur -= seconds(1);
-        subsec_dur += seconds(1);
-      } else {
-        subsec_dur = SubSecDurT::zero();
-      }
-    }
-    return checked_set(sec_out, sec_dur.count()) &&
-           checked_set(subsec_out, subsec_dur.count());
-  }
-};
-
-} // end namespace
-} // end namespace time_detail
-
-using time_detail::fs_time_util;
-
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-#endif // FILESYSTEM_TIME_HELPER_H
diff --git a/lib/libcxx/src/experimental/filesystem/operations.cpp b/lib/libcxx/src/experimental/filesystem/operations.cpp
deleted file mode 100644
index 662fa7b8626..00000000000
--- a/lib/libcxx/src/experimental/filesystem/operations.cpp
+++ /dev/null
@@ -1,808 +0,0 @@
-//===--------------------- filesystem/ops.cpp -----------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "experimental/filesystem"
-#include "iterator"
-#include "fstream"
-#include "type_traits"
-#include "random"  /* for unique_path */
-#include "cstdlib"
-#include "climits"
-
-#include "filesystem_time_helper.h"
-
-#include <unistd.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <fcntl.h>  /* values for fchmodat */
-#if !defined(UTIME_OMIT)
-#include <sys/time.h> // for ::utimes as used in __last_write_time
-#endif
-
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-filesystem_error::~filesystem_error() {}
-
-
-//                       POSIX HELPERS
-
-namespace detail { namespace  {
-
-using value_type = path::value_type;
-using string_type = path::string_type;
-
-inline std::error_code capture_errno() {
-  _LIBCPP_ASSERT(errno, "Expected errno to be non-zero");
-  return std::error_code(errno, std::generic_category());
-}
-
-void set_or_throw(std::error_code const& m_ec, std::error_code* ec,
-                  const char* msg, path const& p = {}, path const& p2 = {})
-{
-    if (ec) {
-        *ec = m_ec;
-    } else {
-        string msg_s("std::experimental::filesystem::");
-        msg_s += msg;
-        __throw_filesystem_error(msg_s, p, p2, m_ec);
-    }
-}
-
-void set_or_throw(std::error_code* ec, const char* msg,
-                  path const& p = {}, path const& p2 = {})
-{
-    return set_or_throw(capture_errno(), ec, msg, p, p2);
-}
-
-perms posix_get_perms(const struct ::stat & st) noexcept {
-    return static_cast<perms>(st.st_mode) & perms::mask;
-}
-
-::mode_t posix_convert_perms(perms prms) {
-    return static_cast< ::mode_t>(prms & perms::mask);
-}
-
-file_status create_file_status(std::error_code& m_ec, path const& p,
-                               struct ::stat& path_stat,
-                               std::error_code* ec)
-{
-    if (ec) *ec = m_ec;
-    if (m_ec && (m_ec.value() == ENOENT || m_ec.value() == ENOTDIR)) {
-        return file_status(file_type::not_found);
-    }
-    else if (m_ec) {
-        set_or_throw(m_ec, ec, "posix_stat", p);
-        return file_status(file_type::none);
-    }
-    // else
-
-    file_status fs_tmp;
-    auto const mode = path_stat.st_mode;
-    if      (S_ISLNK(mode))  fs_tmp.type(file_type::symlink);
-    else if (S_ISREG(mode))  fs_tmp.type(file_type::regular);
-    else if (S_ISDIR(mode))  fs_tmp.type(file_type::directory);
-    else if (S_ISBLK(mode))  fs_tmp.type(file_type::block);
-    else if (S_ISCHR(mode))  fs_tmp.type(file_type::character);
-    else if (S_ISFIFO(mode)) fs_tmp.type(file_type::fifo);
-    else if (S_ISSOCK(mode)) fs_tmp.type(file_type::socket);
-    else                     fs_tmp.type(file_type::unknown);
-
-    fs_tmp.permissions(detail::posix_get_perms(path_stat));
-    return fs_tmp;
-}
-
-file_status posix_stat(path const & p, struct ::stat& path_stat,
-                       std::error_code* ec)
-{
-    std::error_code m_ec;
-    if (::stat(p.c_str(), &path_stat) == -1)
-        m_ec = detail::capture_errno();
-    return create_file_status(m_ec, p, path_stat, ec);
-}
-
-file_status posix_stat(path const & p, std::error_code* ec) {
-    struct ::stat path_stat;
-    return posix_stat(p, path_stat, ec);
-}
-
-file_status posix_lstat(path const & p, struct ::stat & path_stat,
-                        std::error_code* ec)
-{
-    std::error_code m_ec;
-    if (::lstat(p.c_str(), &path_stat) == -1)
-        m_ec = detail::capture_errno();
-    return create_file_status(m_ec, p, path_stat, ec);
-}
-
-file_status posix_lstat(path const & p, std::error_code* ec) {
-    struct ::stat path_stat;
-    return posix_lstat(p, path_stat, ec);
-}
-
-bool stat_equivalent(struct ::stat& st1, struct ::stat& st2) {
-    return (st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino);
-}
-
-//                           DETAIL::MISC
-
-
-bool copy_file_impl(const path& from, const path& to, perms from_perms,
-                    std::error_code *ec)
-{
-    std::ifstream in(from.c_str(), std::ios::binary);
-    std::ofstream out(to.c_str(),  std::ios::binary);
-
-    if (in.good() && out.good()) {
-        using InIt = std::istreambuf_iterator<char>;
-        using OutIt = std::ostreambuf_iterator<char>;
-        InIt bin(in);
-        InIt ein;
-        OutIt bout(out);
-        std::copy(bin, ein, bout);
-    }
-    if (out.fail() || in.fail()) {
-        set_or_throw(make_error_code(errc::operation_not_permitted),
-                     ec, "copy_file", from, to);
-        return false;
-    }
-    __permissions(to, from_perms, ec);
-    // TODO what if permissions fails?
-    return true;
-}
-
-}} // end namespace detail
-
-using detail::set_or_throw;
-
-path __canonical(path const & orig_p, const path& base, std::error_code *ec)
-{
-    path p = absolute(orig_p, base);
-    char buff[PATH_MAX + 1];
-    char *ret;
-    if ((ret = ::realpath(p.c_str(), buff)) == nullptr) {
-        set_or_throw(ec, "canonical", orig_p, base);
-        return {};
-    }
-    if (ec) ec->clear();
-    return {ret};
-}
-
-void __copy(const path& from, const path& to, copy_options options,
-            std::error_code *ec)
-{
-    const bool sym_status = bool(options &
-        (copy_options::create_symlinks | copy_options::skip_symlinks));
-
-    const bool sym_status2 = bool(options &
-        copy_options::copy_symlinks);
-
-    std::error_code m_ec1;
-    struct ::stat f_st = {};
-    const file_status f = sym_status || sym_status2
-                                     ? detail::posix_lstat(from, f_st, &m_ec1)
-                                     : detail::posix_stat(from,  f_st, &m_ec1);
-    if (m_ec1)
-        return set_or_throw(m_ec1, ec, "copy", from, to);
-
-    struct ::stat t_st = {};
-    const file_status t = sym_status ? detail::posix_lstat(to, t_st, &m_ec1)
-                                     : detail::posix_stat(to, t_st, &m_ec1);
-
-    if (not status_known(t))
-        return set_or_throw(m_ec1, ec, "copy", from, to);
-
-    if (!exists(f) || is_other(f) || is_other(t)
-        || (is_directory(f) && is_regular_file(t))
-        || detail::stat_equivalent(f_st, t_st))
-    {
-        return set_or_throw(make_error_code(errc::function_not_supported),
-                            ec, "copy", from, to);
-    }
-
-    if (ec) ec->clear();
-
-    if (is_symlink(f)) {
-        if (bool(copy_options::skip_symlinks & options)) {
-            // do nothing
-        } else if (not exists(t)) {
-            __copy_symlink(from, to, ec);
-        } else {
-            set_or_throw(make_error_code(errc::file_exists),
-                         ec, "copy", from, to);
-        }
-        return;
-    }
-    else if (is_regular_file(f)) {
-        if (bool(copy_options::directories_only & options)) {
-            // do nothing
-        }
-        else if (bool(copy_options::create_symlinks & options)) {
-            __create_symlink(from, to, ec);
-        }
-        else if (bool(copy_options::create_hard_links & options)) {
-            __create_hard_link(from, to, ec);
-        }
-        else if (is_directory(t)) {
-            __copy_file(from, to / from.filename(), options, ec);
-        } else {
-            __copy_file(from, to, options, ec);
-        }
-        return;
-    }
-    else if (is_directory(f) && bool(copy_options::create_symlinks & options)) {
-        return set_or_throw(make_error_code(errc::is_a_directory), ec, "copy");
-    }
-    else if (is_directory(f) && (bool(copy_options::recursive & options) ||
-             copy_options::none == options)) {
-
-        if (!exists(t)) {
-            // create directory to with attributes from 'from'.
-            __create_directory(to, from, ec);
-            if (ec && *ec) { return; }
-        }
-        directory_iterator it = ec ? directory_iterator(from, *ec)
-                                   : directory_iterator(from);
-        if (ec && *ec) { return; }
-        std::error_code m_ec2;
-        for (; it != directory_iterator(); it.increment(m_ec2)) {
-            if (m_ec2) return set_or_throw(m_ec2, ec, "copy", from, to);
-            __copy(it->path(), to / it->path().filename(),
-                   options | copy_options::__in_recursive_copy, ec);
-            if (ec && *ec) { return; }
-        }
-    }
-}
-
-
-bool __copy_file(const path& from, const path& to, copy_options options,
-                 std::error_code *ec)
-{
-    if (ec) ec->clear();
-
-    std::error_code m_ec;
-    auto from_st = detail::posix_stat(from, &m_ec);
-    if (not is_regular_file(from_st)) {
-        if (not m_ec)
-            m_ec = make_error_code(errc::not_supported);
-        set_or_throw(m_ec, ec, "copy_file", from, to);
-        return false;
-    }
-
-    auto to_st = detail::posix_stat(to, &m_ec);
-    if (!status_known(to_st)) {
-        set_or_throw(m_ec, ec, "copy_file", from, to);
-        return false;
-    }
-
-    const bool to_exists = exists(to_st);
-    if (to_exists && !is_regular_file(to_st)) {
-        set_or_throw(make_error_code(errc::not_supported), ec, "copy_file", from, to);
-        return false;
-    }
-    if (to_exists && bool(copy_options::skip_existing & options)) {
-        return false;
-    }
-    else if (to_exists && bool(copy_options::update_existing & options)) {
-        auto from_time = __last_write_time(from, ec);
-        if (ec && *ec) { return false; }
-        auto to_time = __last_write_time(to, ec);
-        if (ec && *ec) { return false; }
-        if (from_time <= to_time) {
-            return false;
-        }
-        return detail::copy_file_impl(from, to, from_st.permissions(), ec);
-    }
-    else if (!to_exists || bool(copy_options::overwrite_existing & options)) {
-        return detail::copy_file_impl(from, to, from_st.permissions(), ec);
-    }
-    else {
-        set_or_throw(make_error_code(errc::file_exists), ec, "copy", from, to);
-        return false;
-    }
-
-    _LIBCPP_UNREACHABLE();
-}
-
-void __copy_symlink(const path& existing_symlink, const path& new_symlink,
-                    std::error_code *ec)
-{
-    const path real_path(__read_symlink(existing_symlink, ec));
-    if (ec && *ec) { return; }
-    // NOTE: proposal says you should detect if you should call
-    // create_symlink or create_directory_symlink. I don't think this
-    // is needed with POSIX
-    __create_symlink(real_path, new_symlink, ec);
-}
-
-
-bool __create_directories(const path& p, std::error_code *ec)
-{
-    std::error_code m_ec;
-    auto const st = detail::posix_stat(p, &m_ec);
-    if (!status_known(st)) {
-        set_or_throw(m_ec, ec, "create_directories", p);
-        return false;
-    }
-    else if (is_directory(st)) {
-        if (ec) ec->clear();
-        return false;
-    }
-    else if (exists(st)) {
-        set_or_throw(make_error_code(errc::file_exists),
-                     ec, "create_directories", p);
-        return false;
-    }
-
-    const path parent = p.parent_path();
-    if (!parent.empty()) {
-        const file_status parent_st = status(parent, m_ec);
-        if (not status_known(parent_st)) {
-            set_or_throw(m_ec, ec, "create_directories", p);
-            return false;
-        }
-        if (not exists(parent_st)) {
-            __create_directories(parent, ec);
-            if (ec && *ec) { return false; }
-        }
-    }
-    return __create_directory(p, ec);
-}
-
-bool __create_directory(const path& p, std::error_code *ec)
-{
-    if (ec) ec->clear();
-    if (::mkdir(p.c_str(), static_cast<int>(perms::all)) == 0)
-        return true;
-    if (errno != EEXIST || !is_directory(p))
-        set_or_throw(ec, "create_directory", p);
-    return false;
-}
-
-bool __create_directory(path const & p, path const & attributes,
-                        std::error_code *ec)
-{
-    struct ::stat attr_stat;
-    std::error_code mec;
-    auto st = detail::posix_stat(attributes, attr_stat, &mec);
-    if (!status_known(st)) {
-        set_or_throw(mec, ec, "create_directory", p, attributes);
-        return false;
-    }
-    if (ec) ec->clear();
-    if (::mkdir(p.c_str(), attr_stat.st_mode) == 0)
-        return true;
-    if (errno != EEXIST || !is_directory(p))
-        set_or_throw(ec, "create_directory", p, attributes);
-    return false;
-}
-
-void __create_directory_symlink(path const & from, path const & to,
-                                std::error_code *ec){
-    if (::symlink(from.c_str(), to.c_str()) != 0)
-        set_or_throw(ec, "create_directory_symlink", from, to);
-    else if (ec)
-        ec->clear();
-}
-
-void __create_hard_link(const path& from, const path& to, std::error_code *ec){
-    if (::link(from.c_str(), to.c_str()) == -1)
-        set_or_throw(ec, "create_hard_link", from, to);
-    else if (ec)
-        ec->clear();
-}
-
-void __create_symlink(path const & from, path const & to, std::error_code *ec) {
-
-    if (::symlink(from.c_str(), to.c_str()) == -1)
-        set_or_throw(ec, "create_symlink", from, to);
-    else if (ec)
-        ec->clear();
-}
-
-path __current_path(std::error_code *ec) {
-    auto size = ::pathconf(".", _PC_PATH_MAX);
-    _LIBCPP_ASSERT(size >= 0, "pathconf returned a 0 as max size");
-
-    auto buff = std::unique_ptr<char[]>(new char[size + 1]);
-    char* ret;
-    if ((ret = ::getcwd(buff.get(), static_cast<size_t>(size))) == nullptr) {
-        set_or_throw(ec, "current_path");
-        return {};
-    }
-    if (ec) ec->clear();
-    return {buff.get()};
-}
-
-void __current_path(const path& p, std::error_code *ec) {
-    if (::chdir(p.c_str()) == -1)
-        set_or_throw(ec, "current_path", p);
-    else if (ec)
-        ec->clear();
-}
-
-bool __equivalent(const path& p1, const path& p2, std::error_code *ec)
-{
-    auto make_unsupported_error = [&]() {
-      set_or_throw(make_error_code(errc::not_supported), ec,
-                     "equivalent", p1, p2);
-      return false;
-    };
-    std::error_code ec1, ec2;
-    struct ::stat st1 = {};
-    struct ::stat st2 = {};
-    auto s1 = detail::posix_stat(p1.native(), st1, &ec1);
-    if (!exists(s1))
-      return make_unsupported_error();
-    auto s2 = detail::posix_stat(p2.native(), st2, &ec2);
-    if (!exists(s2))
-      return make_unsupported_error();
-    if (ec) ec->clear();
-    return (st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino);
-}
-
-
-std::uintmax_t __file_size(const path& p, std::error_code *ec)
-{
-    std::error_code m_ec;
-    struct ::stat st;
-    file_status fst = detail::posix_stat(p, st, &m_ec);
-    if (!exists(fst) || !is_regular_file(fst)) {
-        if (!m_ec)
-            m_ec = make_error_code(errc::not_supported);
-        set_or_throw(m_ec, ec, "file_size", p);
-        return static_cast<uintmax_t>(-1);
-    }
-    // is_regular_file(p) == true
-    if (ec) ec->clear();
-    return static_cast<std::uintmax_t>(st.st_size);
-}
-
-std::uintmax_t __hard_link_count(const path& p, std::error_code *ec)
-{
-    std::error_code m_ec;
-    struct ::stat st;
-    detail::posix_stat(p, st, &m_ec);
-    if (m_ec) {
-        set_or_throw(m_ec, ec, "hard_link_count", p);
-        return static_cast<std::uintmax_t>(-1);
-    }
-    if (ec) ec->clear();
-    return static_cast<std::uintmax_t>(st.st_nlink);
-}
-
-
-bool __fs_is_empty(const path& p, std::error_code *ec)
-{
-    if (ec) ec->clear();
-    std::error_code m_ec;
-    struct ::stat pst;
-    auto st = detail::posix_stat(p, pst, &m_ec);
-    if (m_ec) {
-        set_or_throw(m_ec, ec, "is_empty", p);
-        return false;
-    }
-    else if (!is_directory(st) && !is_regular_file(st)) {
-        m_ec = make_error_code(errc::not_supported);
-        set_or_throw(m_ec, ec, "is_empty");
-        return false;
-    }
-    else if (is_directory(st)) {
-        auto it = ec ? directory_iterator(p, *ec) : directory_iterator(p);
-        if (ec && *ec)
-            return false;
-        return it == directory_iterator{};
-    }
-    else if (is_regular_file(st))
-        return static_cast<std::uintmax_t>(pst.st_size) == 0;
-
-    _LIBCPP_UNREACHABLE();
-}
-
-
-namespace detail { namespace {
-
-using TimeSpec = struct timespec;
-using StatT =  struct stat;
-
-#if defined(__APPLE__)
-TimeSpec extract_mtime(StatT const& st) { return st.st_mtimespec; }
-__attribute__((unused)) // Suppress warning
-TimeSpec extract_atime(StatT const& st) { return st.st_atimespec; }
-#else
-TimeSpec extract_mtime(StatT const& st) { return st.st_mtim; }
-__attribute__((unused)) // Suppress warning
-TimeSpec extract_atime(StatT const& st) { return st.st_atim; }
-#endif
-
-}} // end namespace detail
-
-using FSTime = fs_time_util<file_time_type, time_t, struct timespec>;
-
-file_time_type __last_write_time(const path& p, std::error_code *ec)
-{
-    using namespace ::std::chrono;
-    std::error_code m_ec;
-    struct ::stat st;
-    detail::posix_stat(p, st, &m_ec);
-    if (m_ec) {
-        set_or_throw(m_ec, ec, "last_write_time", p);
-        return file_time_type::min();
-    }
-    if (ec) ec->clear();
-    auto ts = detail::extract_mtime(st);
-    if (!FSTime::is_representable(ts)) {
-        set_or_throw(error_code(EOVERFLOW, generic_category()), ec,
-                     "last_write_time", p);
-        return file_time_type::min();
-    }
-    return FSTime::convert_timespec(ts);
-}
-
-void __last_write_time(const path& p, file_time_type new_time,
-                       std::error_code *ec)
-{
-    using namespace std::chrono;
-    std::error_code m_ec;
-
-    // We can use the presence of UTIME_OMIT to detect platforms that do not
-    // provide utimensat.
-#if !defined(UTIME_OMIT)
-    // This implementation has a race condition between determining the
-    // last access time and attempting to set it to the same value using
-    // ::utimes
-    struct ::stat st;
-    file_status fst = detail::posix_stat(p, st, &m_ec);
-    if (m_ec && !status_known(fst)) {
-        set_or_throw(m_ec, ec, "last_write_time", p);
-        return;
-    }
-    auto atime = detail::extract_atime(st);
-    struct ::timeval tbuf[2];
-    tbuf[0].tv_sec = atime.tv_sec;
-    tbuf[0].tv_usec = duration_cast<microseconds>(nanoseconds(atime.tv_nsec)).count();
-    const bool overflowed = !FSTime::set_times_checked<microseconds>(
-        &tbuf[1].tv_sec, &tbuf[1].tv_usec, new_time);
-
-    if (overflowed) {
-        set_or_throw(make_error_code(errc::invalid_argument), ec,
-                     "last_write_time", p);
-        return;
-    }
-    if (::utimes(p.c_str(), tbuf) == -1) {
-        m_ec = detail::capture_errno();
-    }
-#else
-    struct ::timespec tbuf[2];
-    tbuf[0].tv_sec = 0;
-    tbuf[0].tv_nsec = UTIME_OMIT;
-
-    const bool overflowed = !FSTime::set_times_checked<nanoseconds>(
-        &tbuf[1].tv_sec, &tbuf[1].tv_nsec, new_time);
-    if (overflowed) {
-        set_or_throw(make_error_code(errc::invalid_argument),
-            ec, "last_write_time", p);
-        return;
-    }
-    if (::utimensat(AT_FDCWD, p.c_str(), tbuf, 0) == -1) {
-        m_ec = detail::capture_errno();
-    }
-#endif
-    if (m_ec)
-        set_or_throw(m_ec, ec, "last_write_time", p);
-    else if (ec)
-        ec->clear();
-}
-
-
-void __permissions(const path& p, perms prms, std::error_code *ec)
-{
-
-    const bool resolve_symlinks = !bool(perms::symlink_nofollow & prms);
-    const bool add_perms = bool(perms::add_perms & prms);
-    const bool remove_perms = bool(perms::remove_perms & prms);
-    _LIBCPP_ASSERT(!(add_perms && remove_perms),
-                   "Both add_perms and remove_perms are set");
-
-    bool set_sym_perms = false;
-    prms &= perms::mask;
-    if (!resolve_symlinks || (add_perms || remove_perms)) {
-        std::error_code m_ec;
-        file_status st = resolve_symlinks ? detail::posix_stat(p, &m_ec)
-                                          : detail::posix_lstat(p, &m_ec);
-        set_sym_perms = is_symlink(st);
-        if (m_ec) return set_or_throw(m_ec, ec, "permissions", p);
-        _LIBCPP_ASSERT(st.permissions() != perms::unknown,
-                       "Permissions unexpectedly unknown");
-        if (add_perms)
-            prms |= st.permissions();
-        else if (remove_perms)
-           prms = st.permissions() & ~prms;
-    }
-    const auto real_perms = detail::posix_convert_perms(prms);
-
-# if defined(AT_SYMLINK_NOFOLLOW) && defined(AT_FDCWD)
-    const int flags = set_sym_perms ? AT_SYMLINK_NOFOLLOW : 0;
-    if (::fchmodat(AT_FDCWD, p.c_str(), real_perms, flags) == -1) {
-        return set_or_throw(ec, "permissions", p);
-    }
-# else
-    if (set_sym_perms)
-        return set_or_throw(make_error_code(errc::operation_not_supported),
-                            ec, "permissions", p);
-    if (::chmod(p.c_str(), real_perms) == -1) {
-        return set_or_throw(ec, "permissions", p);
-    }
-# endif
-    if (ec) ec->clear();
-}
-
-
-path __read_symlink(const path& p, std::error_code *ec) {
-    char buff[PATH_MAX + 1];
-    std::error_code m_ec;
-    ::ssize_t ret;
-    if ((ret = ::readlink(p.c_str(), buff, PATH_MAX)) == -1) {
-        set_or_throw(ec, "read_symlink", p);
-        return {};
-    }
-    _LIBCPP_ASSERT(ret <= PATH_MAX, "TODO");
-    _LIBCPP_ASSERT(ret > 0, "TODO");
-    if (ec) ec->clear();
-    buff[ret] = 0;
-    return {buff};
-}
-
-
-bool __remove(const path& p, std::error_code *ec) {
-    if (ec) ec->clear();
-    if (::remove(p.c_str()) == -1) {
-        set_or_throw(ec, "remove", p);
-        return false;
-    }
-    return true;
-}
-
-namespace {
-
-std::uintmax_t remove_all_impl(path const & p, std::error_code& ec)
-{
-    const auto npos = static_cast<std::uintmax_t>(-1);
-    const file_status st = __symlink_status(p, &ec);
-    if (ec) return npos;
-     std::uintmax_t count = 1;
-    if (is_directory(st)) {
-        for (directory_iterator it(p, ec); !ec && it != directory_iterator();
-             it.increment(ec)) {
-            auto other_count = remove_all_impl(it->path(), ec);
-            if (ec) return npos;
-            count += other_count;
-        }
-        if (ec) return npos;
-    }
-    if (!__remove(p, &ec)) return npos;
-    return count;
-}
-
-} // end namespace
-
-std::uintmax_t __remove_all(const path& p, std::error_code *ec) {
-    std::error_code mec;
-    auto count = remove_all_impl(p, mec);
-    if (mec) {
-        set_or_throw(mec, ec, "remove_all", p);
-        return static_cast<std::uintmax_t>(-1);
-    }
-    if (ec) ec->clear();
-    return count;
-}
-
-void __rename(const path& from, const path& to, std::error_code *ec) {
-    if (::rename(from.c_str(), to.c_str()) == -1)
-        set_or_throw(ec, "rename", from, to);
-    else if (ec)
-        ec->clear();
-}
-
-void __resize_file(const path& p, std::uintmax_t size, std::error_code *ec) {
-    if (::truncate(p.c_str(), static_cast<::off_t>(size)) == -1)
-        set_or_throw(ec, "resize_file", p);
-    else if (ec)
-        ec->clear();
-}
-
-space_info __space(const path& p, std::error_code *ec) {
-    space_info si;
-    struct statvfs m_svfs = {};
-    if (::statvfs(p.c_str(), &m_svfs) == -1)  {
-        set_or_throw(ec, "space", p);
-        si.capacity = si.free = si.available =
-            static_cast<std::uintmax_t>(-1);
-        return si;
-    }
-    if (ec) ec->clear();
-    // Multiply with overflow checking.
-    auto do_mult = [&](std::uintmax_t& out, std::uintmax_t other) {
-      out = other * m_svfs.f_frsize;
-      if (other == 0 || out / other != m_svfs.f_frsize)
-          out = static_cast<std::uintmax_t>(-1);
-    };
-    do_mult(si.capacity, m_svfs.f_blocks);
-    do_mult(si.free, m_svfs.f_bfree);
-    do_mult(si.available, m_svfs.f_bavail);
-    return si;
-}
-
-file_status __status(const path& p, std::error_code *ec) {
-    return detail::posix_stat(p, ec);
-}
-
-file_status __symlink_status(const path& p, std::error_code *ec) {
-    return detail::posix_lstat(p, ec);
-}
-
-path __system_complete(const path& p, std::error_code *ec) {
-    if (ec) ec->clear();
-    return absolute(p, current_path());
-}
-
-path __temp_directory_path(std::error_code* ec) {
-  const char* env_paths[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
-  const char* ret = nullptr;
-
-  for (auto& ep : env_paths)
-    if ((ret = std::getenv(ep)))
-      break;
-  if (ret == nullptr)
-    ret = "/tmp";
-
-  path p(ret);
-  std::error_code m_ec;
-  if (!exists(p, m_ec) || !is_directory(p, m_ec)) {
-    if (!m_ec || m_ec == make_error_code(errc::no_such_file_or_directory))
-      m_ec = make_error_code(errc::not_a_directory);
-    set_or_throw(m_ec, ec, "temp_directory_path");
-    return {};
-  }
-
-  if (ec)
-    ec->clear();
-  return p;
-}
-
-// An absolute path is composed according to the table in [fs.op.absolute].
-path absolute(const path& p, const path& base) {
-    auto root_name = p.root_name();
-    auto root_dir = p.root_directory();
-
-    if (!root_name.empty() && !root_dir.empty())
-      return p;
-
-    auto abs_base = base.is_absolute() ? base : absolute(base);
-
-    /* !has_root_name && !has_root_dir */
-    if (root_name.empty() && root_dir.empty())
-    {
-      return abs_base / p;
-    }
-    else if (!root_name.empty()) /* has_root_name && !has_root_dir */
-    {
-      return  root_name / abs_base.root_directory()
-              /
-              abs_base.relative_path() / p.relative_path();
-    }
-    else /* !has_root_name && has_root_dir */
-    {
-      if (abs_base.has_root_name())
-        return abs_base.root_name() / p;
-      // else p is absolute,  return outside of block
-    }
-    return p;
-}
-
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
diff --git a/lib/libcxx/src/experimental/filesystem/path.cpp b/lib/libcxx/src/experimental/filesystem/path.cpp
deleted file mode 100644
index dd4026cfe13..00000000000
--- a/lib/libcxx/src/experimental/filesystem/path.cpp
+++ /dev/null
@@ -1,448 +0,0 @@
-//===--------------------- filesystem/path.cpp ----------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-#include "experimental/filesystem"
-#include "string_view"
-#include "utility"
-
-namespace { namespace parser
-{
-using namespace std;
-using namespace std::experimental::filesystem;
-
-using string_view_t = path::__string_view;
-using string_view_pair = pair<string_view_t, string_view_t>;
-using PosPtr = path::value_type const*;
-
-struct PathParser {
-  enum ParserState : unsigned char {
-    // Zero is a special sentinel value used by default constructed iterators.
-    PS_BeforeBegin = 1,
-    PS_InRootName,
-    PS_InRootDir,
-    PS_InFilenames,
-    PS_InTrailingSep,
-    PS_AtEnd
-  };
-
-  const string_view_t Path;
-  string_view_t RawEntry;
-  ParserState State;
-
-private:
-  PathParser(string_view_t P, ParserState State) noexcept
-      : Path(P), State(State) {}
-
-public:
-  PathParser(string_view_t P, string_view_t E, unsigned char S)
-      : Path(P), RawEntry(E), State(static_cast<ParserState>(S)) {
-    // S cannot be '0' or PS_BeforeBegin.
-  }
-
-  static PathParser CreateBegin(string_view_t P) noexcept {
-    PathParser PP(P, PS_BeforeBegin);
-    PP.increment();
-    return PP;
-  }
-
-  static PathParser CreateEnd(string_view_t P) noexcept {
-    PathParser PP(P, PS_AtEnd);
-    return PP;
-  }
-
-  PosPtr peek() const noexcept {
-    auto TkEnd = getNextTokenStartPos();
-    auto End = getAfterBack();
-    return TkEnd == End ? nullptr : TkEnd;
-  }
-
-  void increment() noexcept {
-    const PosPtr End = getAfterBack();
-    const PosPtr Start = getNextTokenStartPos();
-    if (Start == End)
-      return makeState(PS_AtEnd);
-
-    switch (State) {
-    case PS_BeforeBegin: {
-      PosPtr TkEnd = consumeSeparator(Start, End);
-      // If we consumed exactly two separators we have a root name.
-      if (TkEnd && TkEnd == Start + 2) {
-        // FIXME Do we need to consume a name or is '//' a root name on its own?
-        // what about '//.', '//..', '//...'?
-        auto NameEnd = consumeName(TkEnd, End);
-        if (NameEnd)
-          TkEnd = NameEnd;
-        return makeState(PS_InRootName, Start, TkEnd);
-      }
-      else if (TkEnd)
-        return makeState(PS_InRootDir, Start, TkEnd);
-      else
-        return makeState(PS_InFilenames, Start, consumeName(Start, End));
-    }
-
-    case PS_InRootName:
-      return makeState(PS_InRootDir, Start, consumeSeparator(Start, End));
-    case PS_InRootDir:
-      return makeState(PS_InFilenames, Start, consumeName(Start, End));
-
-    case PS_InFilenames: {
-      PosPtr SepEnd = consumeSeparator(Start, End);
-      if (SepEnd != End) {
-        PosPtr TkEnd = consumeName(SepEnd, End);
-        if (TkEnd)
-          return makeState(PS_InFilenames, SepEnd, TkEnd);
-      }
-      return makeState(PS_InTrailingSep, Start, SepEnd);
-    }
-
-    case PS_InTrailingSep:
-      return makeState(PS_AtEnd);
-
-    case PS_AtEnd:
-      _LIBCPP_UNREACHABLE();
-    }
-  }
-
-  void decrement() noexcept {
-    const PosPtr REnd = getBeforeFront();
-    const PosPtr RStart = getCurrentTokenStartPos() - 1;
-
-    switch (State) {
-    case PS_AtEnd: {
-      // Try to consume a trailing separator or root directory first.
-      if (PosPtr SepEnd = consumeSeparator(RStart, REnd)) {
-        if (SepEnd == REnd)
-          return makeState((RStart == REnd + 2) ? PS_InRootName : PS_InRootDir,
-                           Path.data(), RStart + 1);
-        // Check if we're seeing the root directory separator
-        auto PP = CreateBegin(Path);
-        bool InRootDir = PP.State == PS_InRootName &&
-            &PP.RawEntry.back() == SepEnd;
-        return makeState(InRootDir ? PS_InRootDir : PS_InTrailingSep,
-                         SepEnd + 1, RStart + 1);
-      } else {
-        PosPtr TkStart = consumeName(RStart, REnd);
-        if (TkStart == REnd + 2 && consumeSeparator(TkStart, REnd) == REnd)
-          return makeState(PS_InRootName, Path.data(), RStart + 1);
-        else
-          return makeState(PS_InFilenames, TkStart + 1, RStart + 1);
-      }
-    }
-    case PS_InTrailingSep:
-      return makeState(PS_InFilenames, consumeName(RStart, REnd) + 1, RStart + 1);
-    case PS_InFilenames: {
-      PosPtr SepEnd = consumeSeparator(RStart, REnd);
-      if (SepEnd == REnd)
-        return makeState((RStart == REnd + 2) ? PS_InRootName : PS_InRootDir,
-                         Path.data(), RStart + 1);
-      PosPtr TkEnd = consumeName(SepEnd, REnd);
-      if (TkEnd == REnd + 2 && consumeSeparator(TkEnd, REnd) == REnd)
-        return makeState(PS_InRootDir, SepEnd + 1, RStart + 1);
-      return makeState(PS_InFilenames, TkEnd + 1, SepEnd + 1);
-    }
-    case PS_InRootDir:
-      return makeState(PS_InRootName, Path.data(), RStart + 1);
-    case PS_InRootName:
-    case PS_BeforeBegin:
-      _LIBCPP_UNREACHABLE();
-    }
-  }
-
-  /// \brief Return a view with the "preferred representation" of the current
-  ///   element. For example trailing separators are represented as a '.'
-  string_view_t operator*() const noexcept {
-    switch (State) {
-    case PS_BeforeBegin:
-    case PS_AtEnd:
-      return "";
-    case PS_InRootDir:
-      return "/";
-    case PS_InTrailingSep:
-      return ".";
-    case PS_InRootName:
-    case PS_InFilenames:
-      return RawEntry;
-    }
-    _LIBCPP_UNREACHABLE();
-  }
-
-  explicit operator bool() const noexcept {
-    return State != PS_BeforeBegin && State != PS_AtEnd;
-  }
-
-  PathParser& operator++() noexcept {
-    increment();
-    return *this;
-  }
-
-  PathParser& operator--() noexcept {
-    decrement();
-    return *this;
-  }
-
-private:
-  void makeState(ParserState NewState, PosPtr Start, PosPtr End) noexcept {
-    State = NewState;
-    RawEntry = string_view_t(Start, End - Start);
-  }
-  void makeState(ParserState NewState) noexcept {
-    State = NewState;
-    RawEntry = {};
-  }
-
-  PosPtr getAfterBack() const noexcept {
-    return Path.data() + Path.size();
-  }
-
-  PosPtr getBeforeFront() const noexcept {
-    return Path.data() - 1;
-  }
-
-  /// \brief Return a pointer to the first character after the currently
-  ///   lexed element.
-  PosPtr getNextTokenStartPos() const noexcept {
-    switch (State) {
-    case PS_BeforeBegin:
-      return Path.data();
-    case PS_InRootName:
-    case PS_InRootDir:
-    case PS_InFilenames:
-      return &RawEntry.back() + 1;
-    case PS_InTrailingSep:
-    case PS_AtEnd:
-      return getAfterBack();
-    }
-    _LIBCPP_UNREACHABLE();
-  }
-
-  /// \brief Return a pointer to the first character in the currently lexed
-  ///   element.
-  PosPtr getCurrentTokenStartPos() const noexcept {
-    switch (State) {
-    case PS_BeforeBegin:
-    case PS_InRootName:
-      return &Path.front();
-    case PS_InRootDir:
-    case PS_InFilenames:
-    case PS_InTrailingSep:
-      return &RawEntry.front();
-    case PS_AtEnd:
-      return &Path.back() + 1;
-    }
-    _LIBCPP_UNREACHABLE();
-  }
-
-  PosPtr consumeSeparator(PosPtr P, PosPtr End) const noexcept {
-    if (P == End || *P != '/')
-      return nullptr;
-    const int Inc = P < End ? 1 : -1;
-    P += Inc;
-    while (P != End && *P == '/')
-      P += Inc;
-    return P;
-  }
-
-  PosPtr consumeName(PosPtr P, PosPtr End) const noexcept {
-    if (P == End || *P == '/')
-      return nullptr;
-    const int Inc = P < End ? 1 : -1;
-    P += Inc;
-    while (P != End && *P != '/')
-      P += Inc;
-    return P;
-  }
-};
-
-string_view_pair separate_filename(string_view_t const & s) {
-    if (s == "." || s == ".." || s.empty()) return string_view_pair{s, ""};
-    auto pos = s.find_last_of('.');
-    if (pos == string_view_t::npos)
-        return string_view_pair{s, string_view_t{}};
-    return string_view_pair{s.substr(0, pos), s.substr(pos)};
-}
-
-string_view_t createView(PosPtr S, PosPtr E) noexcept {
-  return {S, static_cast<size_t>(E - S) + 1};
-}
-
-}} // namespace parser
-
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-using parser::string_view_t;
-using parser::string_view_pair;
-using parser::PathParser;
-using parser::createView;
-
-///////////////////////////////////////////////////////////////////////////////
-//                            path definitions
-///////////////////////////////////////////////////////////////////////////////
-
-constexpr path::value_type path::preferred_separator;
-
-path & path::replace_extension(path const & replacement)
-{
-    path p = extension();
-    if (not p.empty()) {
-      __pn_.erase(__pn_.size() - p.native().size());
-    }
-    if (!replacement.empty()) {
-        if (replacement.native()[0] != '.') {
-            __pn_ += ".";
-        }
-        __pn_.append(replacement.__pn_);
-    }
-    return *this;
-}
-
-///////////////////////////////////////////////////////////////////////////////
-// path.decompose
-
-string_view_t path::__root_name() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName)
-      return *PP;
-    return {};
-}
-
-string_view_t path::__root_directory() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName)
-      ++PP;
-    if (PP.State == PathParser::PS_InRootDir)
-      return *PP;
-    return {};
-}
-
-string_view_t path::__root_path_raw() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName) {
-      auto NextCh = PP.peek();
-      if (NextCh && *NextCh == '/') {
-        ++PP;
-        return createView(__pn_.data(), &PP.RawEntry.back());
-      }
-      return PP.RawEntry;
-    }
-    if (PP.State == PathParser::PS_InRootDir)
-      return *PP;
-    return {};
-}
-
-string_view_t path::__relative_path() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    while (PP.State <= PathParser::PS_InRootDir)
-      ++PP;
-    if (PP.State == PathParser::PS_AtEnd)
-      return {};
-    return createView(PP.RawEntry.data(), &__pn_.back());
-}
-
-string_view_t path::__parent_path() const
-{
-    if (empty())
-      return {};
-    auto PP = PathParser::CreateEnd(__pn_);
-    --PP;
-    if (PP.RawEntry.data() == __pn_.data())
-      return {};
-    --PP;
-    return createView(__pn_.data(), &PP.RawEntry.back());
-}
-
-string_view_t path::__filename() const
-{
-    if (empty()) return {};
-    return *(--PathParser::CreateEnd(__pn_));
-}
-
-string_view_t path::__stem() const
-{
-    return parser::separate_filename(__filename()).first;
-}
-
-string_view_t path::__extension() const
-{
-    return parser::separate_filename(__filename()).second;
-}
-
-////////////////////////////////////////////////////////////////////////////
-// path.comparisons
-int path::__compare(string_view_t __s) const {
-    auto PP = PathParser::CreateBegin(__pn_);
-    auto PP2 = PathParser::CreateBegin(__s);
-    while (PP && PP2) {
-        int res = (*PP).compare(*PP2);
-        if (res != 0) return res;
-        ++PP; ++PP2;
-    }
-    if (PP.State == PP2.State && PP.State == PathParser::PS_AtEnd)
-        return 0;
-    if (PP.State == PathParser::PS_AtEnd)
-        return -1;
-    return 1;
-}
-
-////////////////////////////////////////////////////////////////////////////
-// path.nonmembers
-size_t hash_value(const path& __p) noexcept {
-  auto PP = PathParser::CreateBegin(__p.native());
-  size_t hash_value = 0;
-  std::hash<string_view_t> hasher;
-  while (PP) {
-    hash_value = __hash_combine(hash_value, hasher(*PP));
-    ++PP;
-  }
-  return hash_value;
-}
-
-////////////////////////////////////////////////////////////////////////////
-// path.itr
-path::iterator path::begin() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    iterator it;
-    it.__path_ptr_ = this;
-    it.__state_ = PP.State;
-    it.__entry_ = PP.RawEntry;
-    it.__stashed_elem_.__assign_view(*PP);
-    return it;
-}
-
-path::iterator path::end() const
-{
-    iterator it{};
-    it.__state_ = PathParser::PS_AtEnd;
-    it.__path_ptr_ = this;
-    return it;
-}
-
-path::iterator& path::iterator::__increment() {
-  static_assert(__at_end == PathParser::PS_AtEnd, "");
-  PathParser PP(__path_ptr_->native(), __entry_, __state_);
-  ++PP;
-  __state_ = PP.State;
-  __entry_ = PP.RawEntry;
-  __stashed_elem_.__assign_view(*PP);
-  return *this;
-}
-
-path::iterator& path::iterator::__decrement() {
-  PathParser PP(__path_ptr_->native(), __entry_, __state_);
-  --PP;
-  __state_ = PP.State;
-  __entry_ = PP.RawEntry;
-  __stashed_elem_.__assign_view(*PP);
-  return *this;
-}
-
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM