diff --git a/compiler/coco/core/include/coco/IR/Op.h b/compiler/coco/core/include/coco/IR/Op.h
index 090527e2fd8..7774b73b668 100644
--- a/compiler/coco/core/include/coco/IR/Op.h
+++ b/compiler/coco/core/include/coco/IR/Op.h
@@ -27,6 +27,7 @@
 #include "coco/IR/Part.h"
 #include "coco/IR/Entity.h"
 
+#include <cstdint>
 #include <set>
 
 #include <stdexcept>