[clang] [clang] Implement a bitwise_copyable builtin type trait. (PR #86512)

[Sam McCall via cfe-commits]

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@@ -5056,6 +5056,8 @@ static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
   case UTT_IsStandardLayout:
   case UTT_IsPOD:
   case UTT_IsLiteral:
+  // Clang extension:
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sam-mccall wrote:

AFAIK these are all clang extensions (the `__` versions), so I'm not sure this comment is clear/helpful

https://github.com/llvm/llvm-project/pull/86512