[PATCH] libbacktrace: Move define of HAVE_ZLIB into check for -lz

[Iain Buclaw]

On 31 July 2018 at 16:33, Ian Lance Taylor <iant@google.com> wrote:
> On Sun, Jul 29, 2018 at 7:50 AM, Iain Buclaw <ibuclaw@gdcproject.org> wrote:
>>
>> This is really to suppress the default action-if-found for
>> AC_CHECK_LIBS.  Zlib is not a dependency of libbacktrace, and so it
>> shouldn't be added to LIBS.  When looking at the check, saw that could
>> remove the test for ac_cv_lib_z_compress also.
>
> Thanks, but this doesn't seem like quite the right approach, as seen
> by the fact that HAVE_ZLIB_H was dropped from config.h.in.  I think
> you need to keep the AC_DEFINE out of the AC_CHECK_LIB.  I would guess
> that it would work to just change the default case of AC_CHECK_LIB to
> [;] or something similarly innocuous.
>
> Ian

May I ask you to look at the patch again?  There's two similarly named
variables here, HAVE_LIBZ and HAVE_ZLIB.

Only the unused HAVE_LIBZ has been dropped from config.h.in.  The one
that matters has been left alone, or at least I'm pretty sure of.

Iain.