[clang] [Clang] Add constexpr eval for cmath builtins (PR #194327)

[via cfe-commits]

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@@ -531,6 +551,7 @@ static bool interp__builtin_fmax(InterpState &S, CodePtr OpPC,
   const Floating &LHS = S.Stk.pop<Floating>();
   Floating Result = S.allocFloat(LHS.getSemantics());
 
+  // fmin and fmax handle special values (NaN, INF) per IEEE 754.
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Serosh-commits wrote:

> Same comment.

ditto

https://github.com/llvm/llvm-project/pull/194327