--- a/extensions/libxt_geoip.c
+++ b/extensions/libxt_geoip.c
@@ -59,13 +59,13 @@ geoip_get_subnets(const char *code, uint
 
 	/* Use simple integer vector files */
 	if (nfproto == NFPROTO_IPV6) {
-#if __BYTE_ORDER == _BIG_ENDIAN
+#if BYTE_ORDER == BIG_ENDIAN
 		snprintf(buf, sizeof(buf), GEOIP_DB_DIR "/BE/%s.iv6", code);
 #else
 		snprintf(buf, sizeof(buf), GEOIP_DB_DIR "/LE/%s.iv6", code);
 #endif
 	} else {
-#if __BYTE_ORDER == _BIG_ENDIAN
+#if BYTE_ORDER == BIG_ENDIAN
 		snprintf(buf, sizeof(buf), GEOIP_DB_DIR "/BE/%s.iv4", code);
 #else
 		snprintf(buf, sizeof(buf), GEOIP_DB_DIR "/LE/%s.iv4", code);