[clang] [clang][bytecode] Diagnose reference to non-constexpr variable of const type in C23 constexpr (PR #112211)

[Timm Baeder via cfe-commits]

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@@ -348,6 +348,12 @@ bool CheckConstant(InterpState &S, CodePtr OpPC, const Descriptor *Desc) {
   if (D->isConstexpr())
     return true;
 
+  if (const auto *VD = dyn_cast_if_present<VarDecl>(S.EvaluatingDecl);
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tbaederr wrote:

Why are you checking `EvaluatingDecl` here and not `D`?

https://github.com/llvm/llvm-project/pull/112211