diff --git a/clang/lib/AST/Interp/IntegralAP.h b/clang/lib/AST/Interp/IntegralAP.h
index b2b367f30c238f..a9e34a5b237a19 100644
--- a/clang/lib/AST/Interp/IntegralAP.h
+++ b/clang/lib/AST/Interp/IntegralAP.h
@@ -66,7 +66,7 @@ template <bool Signed> class IntegralAP final {
 
   template <typename T> static IntegralAP from(T Value, unsigned NumBits = 0) {
     assert(NumBits > 0);
-    APSInt Copy = APSInt(APInt(NumBits, Value, Signed), !Signed);
+    APSInt Copy = APSInt(APInt(NumBits, static_cast<int64_t>(Value), Signed), !Signed);
 
     return IntegralAP<Signed>(Copy);
   }