Re: localtime-buffer: Avoid endless recursion in localtime and gmtime

[Jim Meyering]

On Thu, Dec 13, 2018 at 3:12 AM Bruno Haible <address@hidden> wrote:
> When running the gnulib unit tests in sed-4.5.48-58eb on Cygwin, I see
> a crash of the test-gettimeofday.exe program. It is caused by endless
> recursion: rpl_localtime and rpl_gmtime are compiled into endless
> recursions.
>
> You don't see this endless recursion when using a regular Autoconf release.
> But the sed-4.5.48-58eb snapshot is built with an Autoconf snapshot that
> contains a bug: it reports
>
>   checking whether we are cross compiling... yes
>
> (instead of 'no'), and as a consequence
>
>   checking whether gettimeofday clobbers localtime buffer... guessing yes
>
> (instead of 'no'), and thus localtime-buffer.c compiles to non-empty code.
> This code, which was meant to invoke the system's localtime and gmtime
> functions, invokes the gnulib replacements because localtime-buffer.h
> includes <time.h> (which in this case is gnulib's time.h override).
>
>
> This patch fixes the bug in gnulib. The bug in Autoconf is separate.

Wow!
Thank you not only for testing so promptly but also for finding and
fixing a gnulib bug, and for finding the one in autoconf.