Merge r2918:2919 from 1.2 branch: alloca macro params in parentheses.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402241

include/SDL_stdinc.h

@@ -223,10 +223,10 @@ char *alloca();
 # endif
 #endif
 #ifdef HAVE_ALLOCA
-#define SDL_stack_alloc(type, count)    (type*)alloca(sizeof(type)*count)
+#define SDL_stack_alloc(type, count)    (type*)alloca(sizeof(type)*(count))
 #define SDL_stack_free(data)
 #else
-#define SDL_stack_alloc(type, count)    (type*)SDL_malloc(sizeof(type)*count)
+#define SDL_stack_alloc(type, count)    (type*)SDL_malloc(sizeof(type)*(count))
 #define SDL_stack_free(data)            SDL_free(data)
 #endif