Conditionally compile weak attribute.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@29159 72102866-910b-0410-8b05-ffd578937521

Source/NSObject.m

@@ -896,15 +896,19 @@ GSGarbageCollectorLog(char *msg, GC_word arg)
  * Semi-private function in libobjc2 that initialises the classes used for
  * blocks.
  */
+#ifndef __MINGW32__
 BOOL 
 objc_create_block_classes_as_subclasses_of(Class super) __attribute__((weak));
+#endif
 
 + (void)load
 {
+#ifndef __MINGW32__
   /* When NSObject is loaded, register it as the superclass of the block
    * classes */
   if (objc_create_block_classes_as_subclasses_of)
     objc_create_block_classes_as_subclasses_of(self);
+#endif
 }
 
 /**