[clang] [Clang][Sema] Diagnosis for constexpr constructor not initializing a union member (PR #81042)

[Mariya Podchishchaeva via cfe-commits]

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@@ -150,6 +150,8 @@ Improvements to Clang's diagnostics
 
 - Clang now diagnoses member template declarations with multiple declarators.
 - Clang now diagnoses use of the ``template`` keyword after declarative nested name specifiers.
+- Clang now diagnoses constexpr constructor for not initializing atleast one member of union
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Fznamznon wrote:

```suggestion
- Clang now diagnoses constexpr constructor for not initializing at least one member of union
```

https://github.com/llvm/llvm-project/pull/81042