From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@gmail.com>
cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        rosset.filipe@gmail.com, Andrew Dunstan <andrew@dunslane.net>
Subject: Re: sys_siglist[] is causing us trouble again
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Comments: In-reply-to Thomas Munro <thomas.munro@gmail.com>
	message dated "Thu, 16 Jul 2020 11:21:53 +1200"
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Date: Wed, 15 Jul 2020 19:36:38 -0400
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Thomas Munro <thomas.munro@gmail.com> writes:
> On Thu, Jul 16, 2020 at 10:48 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Oddly, we'd not get to this code unless configure set
>> HAVE_DECL_SYS_SIGLIST, so it's defined *somewhere*.

> It looks like glibc very recently decided[1] to hide the declaration,
> but we're using a cached configure test result.

Ah, of course.  I was thinking that Peter had just changed configure
in the last day or so, but that did not affect the back branches.
So it's unsurprising for buildfarm animals to be using cached configure
results.

> I guess rawhide is the RH thing that tracks the bleeding edge?

Yup.  Possibly we should recommend that buildfarm owners running on
non-stable platforms disable autoconf result caching --- I believe
that's "use_accache => undef" in the configuration file.

Alternatively, maybe it'd be bright for the buildfarm script to
discard that cache after any failure (or at least configure or
build failures).

			regards, tom lane