libsupc++: Make the destructor parameter to `__cxa_thread_atexit()` use the `__thisca...

The mingw-w64 implementations of `__cxa_thread_atexit()` and `__cxa_atexit()` have been
using `__thiscall` since two years ago. Using the default calling convention (which is
`__cdecl`) causes crashes as explained in PR83562.

Calling conventions have no effect on x86_64-w64-mingw32.

Reference: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83562
Reference: https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/crt/cxa_thread_atexit.c
Reference: https://sourceforge.net/p/mingw-w64/mingw-w64/ci/f3e0fbb40cbc9f8821db8bd8a0c4dae8ff671e9f/
Reference: https://github.com/msys2/MINGW-packages/issues/7071
Signed-off-by: Liu Hao <lh_mouse@126.com>
    2020-10-08  Liu Hao  <lh_mouse@126.com>

	libstdc++-v3:
	* libsupc++/cxxabi.h: (__cxa_atexit): mark with _GLIBCXX_CDTOR_CALLABI
	(__cxa_thread_atexit): ditto
	* libsupc++/atexit_thread.cc: (__cxa_atexit): mark with
	_GLIBCXX_CDTOR_CALLABI
	(__cxa_thread_atexit): ditto
	(elt): ditto

diff --git a/libstdc++-v3/libsupc++/atexit_thread.cc b/libstdc++-v3/libsupc++/atexit_thread.cc
index e97644f8cd4a222e7e5ffebcb7f5999b5efcffe7..4f7f982ac6bc5c7bdb2771a81499ecaa7d96e006 100644 (file)
--- a/libstdc++-v3/libsupc++/atexit_thread.cc
+++ b/libstdc++-v3/libsupc++/atexit_thread.cc
@@ -30,16 +30,21 @@
 #include <windows.h>
 #endif
 
+// Simplify it a little for this file.
+#ifndef _GLIBCXX_CDTOR_CALLABI
+#  define _GLIBCXX_CDTOR_CALLABI
+#endif
+
 #if _GLIBCXX_HAVE___CXA_THREAD_ATEXIT
 
 // Libc provides __cxa_thread_atexit definition.
 
 #elif _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
 
-extern "C" int __cxa_thread_atexit_impl (void (*func) (void *),
+extern "C" int __cxa_thread_atexit_impl (void (_GLIBCXX_CDTOR_CALLABI *func) (void *),
                                         void *arg, void *d);
 extern "C" int
-__cxxabiv1::__cxa_thread_atexit (void (*dtor)(void *),
+__cxxabiv1::__cxa_thread_atexit (void (_GLIBCXX_CDTOR_CALLABI *dtor)(void *),
                                 void *obj, void *dso_handle)
   _GLIBCXX_NOTHROW
 {
@@ -52,7 +57,7 @@ namespace {
   // One element in a singly-linked stack of cleanups.
   struct elt
   {
-    void (*destructor)(void *);
+    void (_GLIBCXX_CDTOR_CALLABI *destructor)(void *);
     void *object;
     elt *next;
 #ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
@@ -116,7 +121,8 @@ namespace {
 }
 
 extern "C" int
-__cxxabiv1::__cxa_thread_atexit (void (*dtor)(void *), void *obj, void */*dso_handle*/)
+__cxxabiv1::__cxa_thread_atexit (void (_GLIBCXX_CDTOR_CALLABI *dtor)(void *),
+                                void *obj, void */*dso_handle*/)
   _GLIBCXX_NOTHROW
 {
   // Do this initialization once.

diff --git a/libstdc++-v3/libsupc++/cxxabi.h b/libstdc++-v3/libsupc++/cxxabi.h
index 000713ecdf83e9eb0e9af61836cd9fad7fd989fc..3d6217a6fac2c70aa66b0273d72de17891e5b365 100644 (file)
--- a/libstdc++-v3/libsupc++/cxxabi.h
+++ b/libstdc++-v3/libsupc++/cxxabi.h
@@ -125,14 +125,22 @@ namespace __cxxabiv1
 
   // DSO destruction.
   int
+#ifdef _GLIBCXX_CDTOR_CALLABI
+  __cxa_atexit(void (_GLIBCXX_CDTOR_CALLABI *)(void*), void*, void*) _GLIBCXX_NOTHROW;
+#else
   __cxa_atexit(void (*)(void*), void*, void*) _GLIBCXX_NOTHROW;
+#endif
 
   void
   __cxa_finalize(void*);
 
   // TLS destruction.
   int
+#ifdef _GLIBCXX_CDTOR_CALLABI
+  __cxa_thread_atexit(void (_GLIBCXX_CDTOR_CALLABI *)(void*), void*, void *) _GLIBCXX_NOTHROW;
+#else
   __cxa_thread_atexit(void (*)(void*), void*, void *) _GLIBCXX_NOTHROW;
+#endif
 
   // Pure virtual functions.
   void