[clang] Fix math-errno issue (PR #66381)

[Joshua Cranmer via cfe-commits]

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@@ -2313,14 +2313,20 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
       FD->hasAttr<AsmLabelAttr>() ? 0 : BuiltinID;
 
   bool ErrnoOverriden = false;
-  // True if math-errno is overriden via the
+  bool ErrnoOverrideValue = false;
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jcranmer-intel wrote:

This might be easier to understand if you replaced these two variables with a single `std::optional<bool> ErrnoOverride`.

https://github.com/llvm/llvm-project/pull/66381