[clang] [Clang] Fix "Unions cannot be dynamic classes" assertion (PR #217942)

[Shengxin Pei via cfe-commits]

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@@ -6585,6 +6585,9 @@ NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
           return nullptr;
 
         D.setInvalidType();
+      } else if (CurContext->isRecord() && !CurContext->Equals(DC)) {
+        // Keep the diagnosed declaration for recovery, but not as a valid one.
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TPPPP72 wrote:

If the final fix is ​​confirmed to be this approach, then I don't think this comment is necessary, as it is self-evident.

https://github.com/llvm/llvm-project/pull/217942