diff --git a/wutil.h b/wutil.h
index 3355ab148..36d6d0754 100644
--- a/wutil.h
+++ b/wutil.h
@@ -16,6 +16,7 @@
 #include <stdarg.h>
 #include <string>
 #include <utility>
+#include <stdint.h>
 #include "common.h"
 
 /**