External symbols should be imported from the DLL

Author: hmelder

NSBlocks.m

@@ -7,10 +7,14 @@
 #include <assert.h>
 
 #ifdef EMBEDDED_BLOCKS_RUNTIME
-#define BLOCK_STORAGE OBJC_PUBLIC
+#	define BLOCK_STORAGE OBJC_PUBLIC
 #else
-#define BLOCK_STORAGE extern
-#endif
+#	if defined(_WIN32)
+#		define BLOCK_STORAGE __attribute__((dllimport))
+#	else
+#		define BLOCK_STORAGE extern
+#	endif // defined(_WIN32)
+#endif // EMBEDDED_BLOCKS_RUNTIME
 
 BLOCK_STORAGE struct objc_class _NSConcreteGlobalBlock;
 BLOCK_STORAGE struct objc_class _NSConcreteStackBlock;
@@ -76,4 +80,4 @@ PRIVATE void init_early_blocks(void)
 	_NSConcreteMallocBlock.info = objc_class_flag_is_block;
 	_NSConcreteAutoBlock.info = objc_class_flag_is_block;
 	_NSConcreteFinalizingBlock.info = objc_class_flag_is_block;
-}
+}