[llvm] [libc] [libc][math] Implement nan(f|l) functions (PR #76690)

[via llvm-commits]

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@@ -1206,6 +1226,29 @@ LIBC_INLINE StrToNumResult<T> strtofloatingpoint(const char *__restrict src) {
   return {T(result), index, error};
 }
 
+template <class T> LIBC_INLINE StrToNumResult<T> strtonan(const char *arg) {
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lntue wrote:

Nit: this is internal function, expand the function name to `str_to_nan` to make it a bit easier to read.

https://github.com/llvm/llvm-project/pull/76690