Re: [PATCH v2 0/3] detect-compiler: clang updates

From: Jeff King <peff@peff.net>
To: Carlo Arenas <carenas@gmail.com>
Cc: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
	"Junio C Hamano" <gitster@pobox.com>,
	git@vger.kernel.org
Subject: Re: [PATCH v2 0/3] detect-compiler: clang updates
Date: Mon, 9 Aug 2021 14:08:58 -0400	[thread overview]
Message-ID: <YRFvOp+3kjfYdi0q@coredump.intra.peff.net> (raw)
In-Reply-To: <CAPUEsph1ZqE9KtT7ooJEa=jURq+=cG78MXwPxahb7f0YXYHL7g@mail.gmail.com>

On Sat, Aug 07, 2021 at 05:30:39PM -0700, Carlo Arenas wrote:

> On Sat, Aug 7, 2021 at 7:40 AM Jeff King <peff@peff.net> wrote:
> > The distinction does not matter for our script (where we only care about
> > "clang4" and up). I guess the most relevant test would be to get XCode
> > 8.x and see what it says. I expect it to claim "clang 8.1.0" or similar,
> > but actually be clang-3. And therefore not support
> > -Wtautological-constant-out-of-range-compare.
> 
> uses Xcode 7.3 (based on clang 3.8) and either does support that flag
> or ignores it silently
> 
>   https://www.travis-ci.com/github/carenas/git/builds/234772346
> 
> the same was observed with Xcode 8
> 
> both error later and fail to build because of a valid (but harmless)
> -Wformat-extra-args warning that doesn't trigger in later versions

Thanks for testing. I think I was wrong that clang4 is the limit for
that option, though. It comes originally from:

  https://lore.kernel.org/git/20180317160832.GB15772@sigill.intra.peff.net/

where clang4 just happened to be the oldest thing I had access to at the
time, so we used that as a minimum. So probably all of our "clang4"
could really be "any clang" (but it is probably OK to leave it as-is).

-Peff