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

[via cfe-commits]

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@@ -2471,6 +2480,23 @@ static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
   return true;
 }
 
+static bool
+checkUnionConstructorIntializer(Sema &SemaRef, const FunctionDecl *Dcl,
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mahtohappy wrote:

DiagUnionMemberConstExprCtorInitializer will be okay?

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