diff --git a/wmstatus.c b/wmstatus.c
index 29cfa0f..4c91bba 100644
--- a/wmstatus.c
+++ b/wmstatus.c
@@ -20,7 +20,9 @@
 #define LIBERTY_WANT_ASYNC
 #define LIBERTY_WANT_PROTO_MPD
 
-#define _GNU_SOURCE // openat
+// openat, dirfd
+#define _XOPEN_SOURCE 700
+#define _GNU_SOURCE
 
 #include "config.h"
 #undef PROGRAM_NAME