diff --git a/docmaker/types.h b/docmaker/types.h
index 509553f..8d645c3 100644
--- a/docmaker/types.h
+++ b/docmaker/types.h
@@ -4,6 +4,7 @@
 #include <map>
 #include <vector>
 #include <string>
+#include <cstdint>
 
 enum Intrinsic {
   U8, U16, U32, S8, S16, S32