[clang] [Clang][Sema] Diagnosis for constexpr constructor not initializing a union member (PR #81225)

[Shafik Yaghmour via cfe-commits]

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@@ -2393,6 +2391,17 @@ static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
                                              Kind))
             return false;
       }
+    } else if (!Constructor->isDelegatingConstructor()) {
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shafik wrote:

Can you explain why we need this change? 

https://github.com/llvm/llvm-project/pull/81225