diff --git a/include/SDL_byteorder.h b/include/SDL_byteorder.h
index 4708aa8a..a2db1304 100644
--- a/include/SDL_byteorder.h
+++ b/include/SDL_byteorder.h
@@ -44,6 +44,7 @@ static char rcsid =
      defined(__arm__) || \
     (defined(__mips__) && defined(__MIPSEL__)) || \
      defined(__SYMBIAN32__) || \
+     defined(__x86_64__) || \
      defined(__LITTLE_ENDIAN__)
 #define SDL_BYTEORDER	SDL_LIL_ENDIAN
 #else