https://bugs.gentoo.org/903573
--- a/src/3rdparty/chromium/v8/src/base/bit-field.h
+++ b/src/3rdparty/chromium/v8/src/base/bit-field.h
@@ -39,8 +39,11 @@
   static constexpr int kLastUsedBit = kShift + kSize - 1;
   static constexpr U kNumValues = U{1} << kSize;
 
+  #pragma clang diagnostic push
+  #pragma clang diagnostic ignored "-Wenum-constexpr-conversion"
   // Value for the field with all bits set.
   static constexpr T kMax = static_cast<T>(kNumValues - 1);
+  #pragma clang diagnostic pop
 
   template <class T2, int size2>
   using Next = BitField<T2, kShift + kSize, size2, U>;