[clang] Enable AST mutation in the constant evaluator (PR #115168)

[Erich Keane via cfe-commits]

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@@ -8328,6 +8329,13 @@ class ExprEvaluatorBase
 
     const FunctionDecl *Definition = nullptr;
     Stmt *Body = FD->getBody(Definition);
+    if (Info.Ctx.getLangOpts().CPlusPlus26 && Info.getASTMutator() &&
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erichkeane wrote:

Based on our discussion, the C++26 check is probably wrong.

https://github.com/llvm/llvm-project/pull/115168