[Bug libstdc++/110653] Support std::stoi etc. without C99 APIs

["dave.anglin at bell dot net" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110653

--- Comment #20 from dave.anglin at bell dot net ---
On 2023-07-19 6:10 a.m., redi at gcc dot gnu.org wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110653
>
> --- Comment #17 from Jonathan Wakely <redi at gcc dot gnu.org> ---
> (In reply to Jonathan Wakely from comment #16)
>> PASS: 21_strings/basic_string/numeric_conversions/char/stoll.cc (test for
>> excess errors)
>> PASS: 21_strings/basic_string/numeric_conversions/char/stoll.cc execution
>> test
> Oops, sorry, not that one! As mentioned, that will be UNSUPPORTED for hpux11.11
Yes, stoll and stoull tests are UNSUPPORTED.

We also have:
UNSUPPORTED: 21_strings/basic_string/numeric_conversions/char/stold.cc

The rest of the non wide character conversion tests pass.

The stoll and stoull tests pass when dg-require-string-conversions is 1.  The
stold test
fails, I think because it returns LDBL_MAX instead of HUGE_VALL (inf).  See
_GLIBCXX_HAVE_BROKEN_STRTOLD comment in /config/os/hpux/os_defines.h.

There is a problem with std::stof.  It throws an out of range exception for 0. 
It needs to
check for 0 value.