diff --git a/rts/System/Sync/SHA512.cpp b/rts/System/Sync/SHA512.cpp
index ab4e973a23..adc9b3ee47 100644
--- a/rts/System/Sync/SHA512.cpp
+++ b/rts/System/Sync/SHA512.cpp
@@ -2,6 +2,7 @@
 
 #include <cassert>
 #include <cstring>
+#include <cstdio>
 
 #include "SHA512.hpp"