[clang] [CLANG] Add warning when comparing to INF or NAN in fast math mode. (PR #76873)

[Andy Kaylor via cfe-commits]

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@@ -2267,6 +2273,16 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
   case Builtin::BI__builtin_signbit:
   case Builtin::BI__builtin_signbitf:
   case Builtin::BI__builtin_signbitl:
+    FPO = TheCall->getFPFeaturesInEffect(getLangOpts());
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andykaylor wrote:

Should these checks be in SemaBuiltinFPClassification()?

https://github.com/llvm/llvm-project/pull/76873