strtold
long double strtold(const char * __restrict, char ** __restrict);
__weak_alias(strtold, _strtold)
__weak_alias(strtold, _strtold)
#define NAN_STRTOD strtold
ld = strtold("1e309", &eptr);
volatile long double ld = strtold(inf_strings[i], NULL);
volatile long double ld = strtold(nan_string, &end);
long double val = strtold(testcases[i].str, &end);
val = strtold(*gargv, &ep);
long double ld = strtold(cp, &eptr);