--- a/lib/hard-locale.c	(index)
+++ b/lib/hard-locale.c	(working tree)
@@ -19,6 +19,7 @@
 #include <config.h>
 
 #include "hard-locale.h"
+#include "setlocale_null.h"
 
 #include <locale.h>
 #include <string.h>