[Buildroot] [PATCH v1] package/cvs: fix mktime related compile failure

[Peter Seiderer <ps.report@gmx.net>]

Hello Thomas,

On Thu, 28 May 2020 22:43:35 +0200, Thomas Petazzoni <thomas.petazzoni@bootlin.com> wrote:

> On Thu, 28 May 2020 22:32:04 +0200
> Peter Seiderer <ps.report@gmx.net> wrote:
>
> > Use ac_cv_func_working_mktime=yes to force the use of a provided
> > mktime implementation instead of compiling the failing own one.
> >
> > Fixes:
> >
> >   http://autobuild.buildroot.net/results/5bcd8f4235002da682cc900f866116d2fe87f1c8
> >
> >   mktime.c: In function 'ydhms_diff':
> >   mktime.c:106:52: error: size of array 'a' is negative
> >    #define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
> >                                                       ^
> >   mktime.c:170:3: note: in expansion of macro 'verify'
> >      verify (long_int_year_and_yday_are_wide_enough,
> >      ^~~~~~
> >
> > Signed-off-by: Peter Seiderer <ps.report@gmx.net>
>
> Why is this suddenly failing? We have had this package for ages, it
> hasn't been changed recently.
>
> So instead of just fixing the issue, we always want to understand *why*
> we started having an issue.
>
> Do you have some details of this ?

Sorry for being (too) short in the commit log, the failure/assert comes from the lines:

  verify (long_int_year_and_yday_are_wide_enough,
          INT_MAX <= LONG_MAX / 2 || TIME_T_MAX <= UINT_MAX);

And happens with musl libc, I believe another fail out from the y2038
time_t conversion from 32bit to 64bit...

Regards,
Peter

>
> Thomas