From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: Breakage (?) in configure and git_vsnprintf()
Date: Mon, 12 Dec 2011 15:56:45 -0600
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References: <4EE4F97B.9000202@alum.mit.edu>
 <20111212064305.GA16511@sigill.intra.peff.net>
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Cc: Michael Haggerty <mhagger@alum.mit.edu>,
	Junio C Hamano <gitster@pobox.com>,
	git discussion list <git@vger.kernel.org>,
	Michal Rokos <michal.rokos@nextsoft.cz>,
	Brandon Casey <casey@nrlssc.navy.mil>
To: Jeff King <peff@peff.net>
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Jeff King wrote:

> I'll leave the issue of "-std=c89" triggering SNPRINTF_RETURNS_BOGUS to
> people who know and care about autoconf. My gut is to say "don't do
> that". Git is not actually pure c89. We typically target systems that
> are _at least_ c89, but it's more important to match and run well on
> real-world systems than what was defined in the standard. So we don't
> depend on c99, but we do depend on quirks and features that were
> prominent in mid-90's Unix variants.

Using vsnprintf isn't even wrong from the standards-pedant point of
view --- vsnprintf has been in POSIX for a long time.  The problem is
that the configure script is not setting appropriate feature test
macros such as _XOPEN_SOURCE (like git-compat-util.h does) during its
feature tests.

Maybe it would be possible to hook the appropriate magic into
AC_LANG_PROGRAM.