From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id D580D3850401; Tue, 28 Jul 2020 05:57:09 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D580D3850401
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
 s=default; t=1595915829;
 bh=mk2I2HsgSwjcfHBi1hEZg2ZYOG9FzHmlaiNlRksmFXs=;
 h=From:To:Subject:Date:In-Reply-To:References:From;
 b=TxsHslaeQt/GwZyCxvUT42T7CVtB/jgOy36zyqZn/CZGfnJYbSU0tS3Z1GK3ykKVk
 AJB7NxWnfViOJdrn6Eg8GN/TfIjBy16oM9a9u9VGApk2UEiCq8EFyVDUQl3OnfuLrF
 3dPiG1PEIbEn08KW6ZvRe93sekS1yW477S2hn8ao=
From: "egallager at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/96284] Outdated C features should be made errors with newer
 standards
Date: Tue, 28 Jul 2020 05:57:09 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Version: unknown
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: egallager at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-96284-4-ebFUvnENvH@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-96284-4@http.gcc.gnu.org/bugzilla/>
References: <bug-96284-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <http://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <http://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Jul 2020 05:57:09 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96284

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.o=
rg,
                   |                            |fw at gcc dot gnu.org

--- Comment #5 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to David Brown from comment #0)
> While C has tried to remain backwards compatible with each new standards
> revision, some changes have been made so that particularly unsafe features
> from old code are no longer supported.  gcc has (reasonably enough) tried=
 to
> keep support for old features, but when something has been deprecated for
> decades, perhaps it is time for it to be treated as an error by default a=
nd
> require an explicit flag.  (This is in the same style as bug 85678 making
> "-fno-common" the default.)
>=20
> For example, implicit function declarations from K&R C were made obsolesc=
ent
> in C90, and removed from the language in C99.  But by default, they still
> only cause a warning (-Wimplicit-function-declaration) in gcc, no matter
> what standard is picked.
>=20
> Could this be made an error by default
> (-Werror=3Dimplicit-function-declarations) ?  Let those who want to compi=
le
> old code with implicit function declarations, do so with an explicit flag.

I think Florian Weimer tried this and it broke the majority of configure
scripts in existence...=