Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: Valdis Kletnieks <valdis@vt.edu>
From:   "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" <valdis.kletnieks@vt.edu>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Kees Cook <keescook@chromium.org>, linux-hardening@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH] gcc-plugins: fix gcc 11 indigestion with plugins...
In-Reply-To: <CAMuHMdXR09QdSiziQQ_XuPcJPOca_+mK1jYYHj3VsP_eCu_KbA@mail.gmail.com>
References: <82487.1609006918@turing-police> <160997457204.3687425.15622431721220616573.b4-ty@chromium.org> <CAMuHMdU1YSODgh_T5RxqUqorveAQiy_-gQbF_SwMEj7gvG25qw@mail.gmail.com> <122278.1610362619@turing-police>
 <CAMuHMdXR09QdSiziQQ_XuPcJPOca_+mK1jYYHj3VsP_eCu_KbA@mail.gmail.com>
Mime-Version: 1.0
Content-Type: multipart/signed; boundary="==_Exmh_1610368277_16026P";
         micalg=pgp-sha1; protocol="application/pgp-signature"
Content-Transfer-Encoding: 7bit
Date:   Mon, 11 Jan 2021 07:31:17 -0500
Message-ID: <128149.1610368277@turing-police>
Precedence: bulk

--==_Exmh_1610368277_16026P
Content-Type: text/plain; charset=us-ascii

On Mon, 11 Jan 2021 05:56:59 -0500, I said:

> > It's probably related. I'm just having a hard time understanding why 4.9 and 5.4
> > whine about the lack of a space, while 8.3 and 11 didn't complain...

So after more digging, at least some clarity has surfaced.

It looks like it's not a kernel source tree issue, it's a g++ issue fixed in g++ 6 and later.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69959

And it looks like there was an intent to backport it to 4.9 and 5.4:
https://gcc.gnu.org/legacy-ml/gcc-patches/2016-02/msg01409.html

The bugtracker doesn't show an equivalent for 69959 being closed against 4.9.x or 5.[56],

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63254 has a patch for one of the
gcc-supplied files that tosses the warning, but that way lies madness...

Not sure what we want to do here - the main alternatives I see are:

Tell people still using 4.9/5.4 to either live with the warning or upgrade to 6 or later

Make the flag a variable and pass either -std=gnu++98 or -std=gnu++11
depending on the output of 'g++ --version'

What say the peanut gallery?

--==_Exmh_1610368277_16026P
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Comment: Exmh version 2.9.0 11/07/2018
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=mGP8
-----END PGP SIGNATURE-----

--==_Exmh_1610368277_16026P--