--- src/libs/mips_swap.h
+++ src/libs/mips_swap.h
@@ -20,8 +20,8 @@
 
 #include "general.h"
 
-#ifndef WORDS_BIGENDIAN    /* reverse byteorder */
-
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+/* reverse byteorder */
 /* the following works even for badly aligned pointers */
 
 #define SWAPFIELD(x) {if     (sizeof(*(x))==sizeof(short)) {SWAPHALF((x))}  \