static char *check_nan_suffix(char *s) { char *start = s; if (*s++ != '(') return start; while ((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') || (*s >= '0' && *s <= '9') || *s == '_') s++; return *s == ')' ? s + 1 : start; }