There's a bug in the VC7 optimizer relating to the duff loop optimization

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40554

src/video/SDL_blit.h

@@ -375,7 +375,11 @@ do {						\
 } while(0)
 
 /* This is a very useful loop for optimizing blitters */
+#if defined(_MSC_VER) && (_MSC_VER == 1300)
+/* There's a bug in the Visual C++ 7 optimizer when compiling this code */
+#else
 #define USE_DUFFS_LOOP
+#endif
 #ifdef USE_DUFFS_LOOP
 
 /* 8-times unrolled loop */