diff --git a/src/stdlib/SDL_string.c b/src/stdlib/SDL_string.c
index 8c44e6d69..0ab5af6bb 100644
--- a/src/stdlib/SDL_string.c
+++ b/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--;
     }