[clang] [Clang] Implement P2280R4 Using unknown pointers and references in constant expressions (PR #95474)

[Mariya Podchishchaeva via cfe-commits]

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@@ -3358,7 +3373,9 @@ static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E,
   // FIXME: We should eventually check whether the variable has a reachable
   // initializing declaration.
   const Expr *Init = VD->getAnyInitializer(VD);
-  if (!Init) {
+  // P2280R4 struck the restriction that variable of referene type should have
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Fznamznon wrote:

```suggestion
  // P2280R4 struck the restriction that variable of reference type should have
```

https://github.com/llvm/llvm-project/pull/95474