diff --git a/src/windows.c b/src/windows.c
index a57bf3f7..099c62d7 100644
--- a/src/windows.c
+++ b/src/windows.c
@@ -22,6 +22,7 @@
 
 #include "config.h"
 
+#include <stdlib.h>
 #include <string.h>
 
 #include <glib.h>