[clang] [Clang][Driver] Override complex number calculation method by -fno-fast-math (PR #132680)

[Fangrui Song via cfe-commits]

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@@ -2997,6 +2997,7 @@ static void RenderFloatingPointOptions(const ToolChain &TC, const Driver &D,
   LangOptions::ComplexRangeKind Range = LangOptions::ComplexRangeKind::CX_None;
   std::string ComplexRangeStr = "";
   std::string GccRangeComplexOption = "";
+  std::string LastComplexRangeOption = "";
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MaskRay wrote:

`= ""` is unnecessary. The  newly introduced variable can drop `= ""`. You can also drop `= ""` for the two existing variables as this is minor change.

https://github.com/llvm/llvm-project/pull/132680