diff --git a/src/bin/clockconfig.c b/src/bin/clockconfig.c
index fea4385c97..efa0318c33 100644
--- a/src/bin/clockconfig.c
+++ b/src/bin/clockconfig.c
@@ -6,6 +6,7 @@
 
 #include <FindDirectory.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <OS.h>