1 files changed, 3 insertions, 1 deletions
diff --git a/text.c b/text.c
index 134d507..bc0be04 100644
--- a/text.c
+++ b/text.c
@@ -1,4 +1,6 @@
-#define _GNU_SOURCE // memrchr(3) is non-standard
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE /* memrchr(3) is non-standard */
+#endif
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>