bug#12206: test-parse-datetime regression test failure with glibc-2.16.0

[Jim Meyering]

Paul Eggert wrote:
> On 08/17/2012 10:46 AM, Bruce Dubbs wrote:
>> I've never seen the M parameters in TZ before.  What do they do?
>
> They specify the time zone rules directly, without consulting
> the tz database.  Unlike the tz database, they're specified by
> POSIX, so they should be more portable.  Also, POSIX says they
> ignore leap seconds so they should not have a leap second glitch.
>
> I suspect you've found a glibc bug in its handling of tm_gmtoff
> and/or localtime-vs-gmtime when leap seconds are enabled,
> which you're welcome to report.
>
> This code is supposed to be testing parse-datetime, not
> for glibc bugs, so I pushed the following patch into gnulib
> and am marking this as done.  The fix should be propagated into
> coreutils the next time it syncs from gnulib.
>
> test-parse-datetime: avoid glibc leap-second glitch
> * tests/test-parse-datetime.c (main): Set TZ to US Eastern time
> with the 2012 rules.  Problem reported by Bruce Dubbs in
> <http://bugs.gnu.org/12206>.
> diff --git a/tests/test-parse-datetime.c b/tests/test-parse-datetime.c
> index 1c9fd2d..98ce64b 100644
> --- a/tests/test-parse-datetime.c
> +++ b/tests/test-parse-datetime.c
> @@ -123,6 +123,12 @@ main (int argc _GL_UNUSED, char **argv)
>
>    set_program_name (argv[0]);
>
> +  /* Set the time zone to US Eastern time with the 2012 rules.  This
> +     should disable any leap second support.  Otherwise, there will be
> +     a problem with glibc on sites that default to leap seconds; see
> +     <http://bugs.gnu.org/12206>.  */
> +  setenv ("TZ", "EST5EDT,M3.2.0,M11.1.0", 1);
> +
>    gmtoff = gmt_offset (ref_time);

Thanks for the quick fix, Paul.
This will be fixed in coreutils-8.19, coming soon.