Re: strtold() availability

[VÃclav Zeman <vhaisman at gmail dot com>]

On 10 March 2014 11:39, Corinna Vinschen wrote:
> On Mar 10 10:11, VÃclav Zeman wrote:
>> On 7 March 2014 21:08, Corinna Vinschen wrote:
>> > On Mar  7 17:04, VÃclav Zeman wrote:
>> >> Hi.
>> >>
>> >> This bit from /usr/include/stdlib.h hides the `strtold()` function
>> >> even though the `strtold` symbol appears to be exported from
>> >> `cygwin1.dll`:
>> >>
>> >> ~~~~{.c}
>> >> /* On platforms where long double equals double.  */
>> >> #ifdef _LDBL_EQ_DBL
>> >> #if !defined(__STRICT_ANSI__) || (__STDC_VERSION__ >= 199901L) ||
>> >> (__cplusplus >= 201103L)
>> >> extern long double strtold (const char *__restrict, char **__restrict);
>> >> #endif
>> >> #endif /* _LDBL_EQ_DBL */
>> >> ~~~~
>> >>
>> >> This in turn breaks my source because I cannot use `_GLIBCXX_USE_C99`
>> >> to expose some C++11 features like `std::vsnprintf()`.
>> >>
>> >> Shouldn't the `_LDBL_EQ_DBL` guard be removed and the function exposed
>> >> regardless of `double` and `long double` sizes?
>> >
>> > I fixed that in newlib after a discussion with my co-maintainer.
>> > strtold now gets defined if _HAVE_LONG_DOUBLE is defined.  This is
>> > the case for Cygwin, for instance.
>>
>> I think that similar fix needs to be applied to `wchar.h` and `wcstold()`.
>
> Not yet.  Newlib doesn't provide wcstold, only wcstod.

I see this in `/usr/include/wchar.h`:

~~~~{.c}
/* On platforms where long double equals double.  */
#ifdef _LDBL_EQ_DBL
long double _EXFUN(wcstold, (const wchar_t *, wchar_t **));
#endif /* _LDBL_EQ_DBL */
~~~~

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple