1 files changed, 7 insertions, 1 deletions
diff --git a/lib/libcxx/src/condition_variable.cpp b/lib/libcxx/src/condition_variable.cpp
index bfb4bf3925f..2200aefb804 100644
--- a/lib/libcxx/src/condition_variable.cpp
+++ b/lib/libcxx/src/condition_variable.cpp
@@ -14,7 +14,7 @@
 #include "condition_variable"
 #include "thread"
 #include "system_error"
-#include "cassert"
+#include "__undef_macros"
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
@@ -79,6 +79,12 @@ condition_variable::__do_timed_wait(unique_lock<mutex>& lk,
 void
 notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk)
 {
+    auto& tl_ptr = __thread_local_data();
+    // If this thread was not created using std::thread then it will not have
+    // previously allocated.
+    if (tl_ptr.get() == nullptr) {
+        tl_ptr.set_pointer(new __thread_struct);
+    }
     __thread_local_data()->notify_all_at_thread_exit(&cond, lk.release());
 }