[clang] [CLANG] Full support of complex multiplication and division. (PR #81514)

[Andy Kaylor via cfe-commits]

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@@ -2807,9 +2791,17 @@ static void RenderFloatingPointOptions(const ToolChain &TC, const Driver &D,
     FPExceptionBehavior = "";
     // If fast-math is set then set the fp-contract mode to fast.
     FPContract = "fast";
-    // ffast-math enables limited range rules for complex multiplication and
+    // ffast-math enables basic range rules for complex multiplication and
     // division.
-    Range = LangOptions::ComplexRangeKind::CX_Limited;
+    // Warn if user expects to perform full implementation of complex
+    // multiplication or division in the presence of nnan or ninf flags.
+    if (Range == LangOptions::ComplexRangeKind::CX_Full)
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andykaylor wrote:

Shouldn't we also warn if this is overriding promoted or improved?

https://github.com/llvm/llvm-project/pull/81514