[clang] [Clang][RFC] Intrododuce a builtin to determine the structure binding size (PR #131515)

[via cfe-commits]

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@@ -5327,7 +5327,19 @@ void CXXNameMangler::mangleExpression(const Expr *E, unsigned Arity,
       }
     };
 
-    switch(SAE->getKind()) {
+    auto MangleExtensionBuiltin = [&](const UnaryExprOrTypeTraitExpr *E,
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cor3ntin wrote:

Nope, I need to factor it out now...

https://github.com/llvm/llvm-project/pull/131515