From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12836 invoked by alias); 2 Mar 2011 10:52:07 -0000 Received: (qmail 12828 invoked by uid 22791); 2 Mar 2011 10:52:06 -0000 X-SWARE-Spam-Status: No, hits=-2.8 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 02 Mar 2011 10:52:00 +0000 From: "manu at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/36299] spurious and undocumented warning with -Waddress for a == 0 when a is an array X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: manu at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Date: Wed, 02 Mar 2011 10:52:00 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2011-03/txt/msg00157.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D36299 --- Comment #8 from Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez 2011-03-02 10:51:51 UTC --- (In reply to comment #7) > (In reply to comment #6) > > I think the intention is to warn, at least for a =3D=3D (void *)0, sinc= e the > > address of a cannot be zero or null. So I would say that this is a regr= ession. >=20 > But this is valid in C, and in practice, such a test can occur in macro > expansions: a macro can check whether some pointer is null before doing > something with it. There shouldn't be a warning in such a case. Every warning warns about something valid in C, otherwise it would be an er= ror not a warning.