re PR libstdc++/52300 (Gthreads functions linking error at dynamic linking with…

re PR libstdc++/52300 (Gthreads functions linking error at dynamic linking with libstdc++ when using MinGW.)

       PR libstdc++/52300
       * gthr.h (GTHREAD_USE_WEAK): Define as zero for mingw.

From-SVN: r184406

libgcc/ChangeLog

 2012-02-20  Kai Tietz  <ktietz@redhat.com>
 
+	PR libstdc++/52300
+	* gthr.h (GTHREAD_USE_WEAK): Define as zero for mingw.
+
 	* config.host (i686-*-mingw*): Set md_unwind_header only for dw2-mode
 	to w32-unwind.h header.
 

libgcc/gthr.h

@@ -135,6 +135,14 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 */
 
 #if SUPPORTS_WEAK
+/* The pe-coff weak support isn't fully compatible to ELF's weak.
+   For static libraries it might would work, but as we need to deal
+   with shared versions too, we disable it for mingw-targets.  */
+#ifdef __MINGW32__
+#undef GTHREAD_USE_WEAK
+#define GTHREAD_USE_WEAK 0
+#endif
+
 #ifndef GTHREAD_USE_WEAK
 #define GTHREAD_USE_WEAK 1
 #endif