diff --git a/src/uint256.h b/src/uint256.h
index 0add8040..320ee7e9 100644
--- a/src/uint256.h
+++ b/src/uint256.h
@@ -8,6 +8,7 @@
 #include "serialize.h"
 
 #include <limits.h>
+#include <stdio.h>
 #include <string>
 #include <vector>