[clang] [clang] Diagnose [[nodiscard]] return types in Objective-C++ (PR #142541)

[Erich Keane via cfe-commits]

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@@ -272,6 +273,26 @@ QualType ObjCMessageExpr::getCallReturnType(ASTContext &Ctx) const {
   return Ctx.getReferenceQualifiedType(this);
 }
 
+std::pair<const NamedDecl *, const Attr *>
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erichkeane wrote:

I think we're decades past 'maybe we'll support other kinds some day' :D  

If you're willing to do the change on `CallExpr` at the same time, please do.

https://github.com/llvm/llvm-project/pull/142541