diff --git a/libretro-common/file/nbio/nbio_linux.c b/libretro-common/file/nbio/nbio_linux.c
index 7b40551194..3395a2cef7 100644
--- a/libretro-common/file/nbio/nbio_linux.c
+++ b/libretro-common/file/nbio/nbio_linux.c
@@ -24,7 +24,9 @@
 
 #if defined(__linux__)
 
+#ifndef _GNU_SOURCE
 #define _GNU_SOURCE
+#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>