[clang] [Clang] handle [[warn_unused]] attribute for unused private fields (PR #120734)

[Oleksandr T. via cfe-commits]

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@@ -3307,6 +3307,29 @@ void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
   }
 }
 
+template <typename AttrType>
+inline static bool HasAttribute(const QualType &T) {
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a-tarasyuk wrote:

@AaronBallman could you take a look at this issue? thanks

https://github.com/llvm/llvm-project/pull/120734