C fallback for SDL_revcpy() was off by one. Thanks to Emmanuel Jeandel for

the catch.

  Fixes Bugzilla #424.

--HG--
branch : SDL-1.2

src/stdlib/SDL_string.c

@@ -289,8 +289,8 @@ void *SDL_revcpy(void *dst, const void *src, size_t len)
 {
     char *srcp = (char *)src;
     char *dstp = (char *)dst;
-    srcp += len;
-    dstp += len;
+    srcp += len-1;
+    dstp += len-1;
     while ( len-- ) {
         *dstp-- = *srcp--;
     }