[clang] [CLANG] Add warning when INF or NAN are used in a binary operation or as function argument in fast math mode. (PR #76873)

[Zahira Ammarguellat via cfe-commits]

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@@ -6771,6 +6771,9 @@ def warn_pointer_sub_null_ptr : Warning<
 def warn_floatingpoint_eq : Warning<
   "comparing floating point with == or != is unsafe">,
   InGroup<DiagGroup<"float-equal">>, DefaultIgnore;
+def warn_fast_floatingpoint_eq : Warning<
+  "explicit comparison with %0 when the program is assumed to not use or produce %0">,
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zahiraam wrote:

Not sure this makes sense. Since I am also adding this warning to things like a * INF/NaN or foo(INF).

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