Set _LIBCPP_TLS_DESTRUCTOR_CC convention to run_dtors

[pirama]

Summary

This function is passed as the at_exit parameter to
libcpp_tls_create. This parameter is marked with the
_LIBCPP_TLS_DESTRUCTOR_CC attribute. The macro is empty for pthread,
and set to stdcall for other threading models. stdcall is in turn
emptry for most cases. That's likely why this doesn't fail now.

The one exception is Windows on i686 with the Win32 threading API, where
the stdcall calling convention is used.

[pirama]

Ping...

[pirama]

This file is not built for WIN32.

src/cxa_thread_atexit.cpp

namespace {
 
   // The linked list of thread-local destructors to run
   __thread DtorList* dtors = nullptr;
   // True if the destructors are currently scheduled to run on this thread
   __thread bool dtors_alive = false;
   // Used to trigger destructors on thread exit; value is ignored
   std::__libcpp_tls_key dtors_key;
 
-  void run_dtors(void*) {
+  void _LIBCPP_TLS_DESTRUCTOR_CC run_dtors(void*) {
     while (auto head = dtors) {
       dtors = head->next;
       head->dtor(head->obj);
       std::free(head);
     }
 
     dtors_alive = false;
   }