[clang] [llvm] [C++23] [CLANG] Adding C++23 constexpr math functions: fmin, fmax and frexp. (PR #88978)

[Zahira Ammarguellat via cfe-commits]

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@@ -3452,9 +3452,10 @@ def Fmod : FPMathTemplate, LibBuiltin<"math.h"> {
 
 def Frexp : FPMathTemplate, LibBuiltin<"math.h"> {
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zahiraam wrote:

I have added `UnprefixedOnlyConstexprSince` to the class `LIBBUILTIN` so it will be unknow if I add it to this def. I will wait to see if the changes I made were correct and update this rule accordingly.

https://github.com/llvm/llvm-project/pull/88978