From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 39812 invoked by alias); 23 Oct 2015 09:23:29 -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 Received: (qmail 39774 invoked by uid 48); 23 Oct 2015 09:23:26 -0000 From: "manu at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/68052] No printf format warnings in C++ code for macro in system headers Date: Fri, 23 Oct 2015 09:23:00 -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: 5.2.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: manu at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED 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: Message-ID: In-Reply-To: References: 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-SW-Source: 2015-10/txt/msg01930.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D68052 --- Comment #5 from Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez --- (In reply to Olivier Blin from comment #3) > Quoting Martin Sebor's answer from the gcc-help mailing list: > https://gcc.gnu.org/ml/gcc-help/2015-10/msg00128.html What Martin describes there is a different bug that occurs when there is a whole stack of macro expansions (which is not the case in the original testcase). My guess is that it is https://gcc.gnu.org/PR52998 Most of the bugs in the macro unwinder are known and triaged, but no one has stepped up to fix them. See I) at https://gcc.gnu.org/wiki/Better_Diagnosti= cs >>From gcc-bugs-return-500376-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Fri Oct 23 09:35:42 2015 Return-Path: Delivered-To: listarch-gcc-bugs@gcc.gnu.org Received: (qmail 70103 invoked by alias); 23 Oct 2015 09:35:41 -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 Delivered-To: mailing list gcc-bugs@gcc.gnu.org Received: (qmail 70079 invoked by uid 48); 23 Oct 2015 09:35:37 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/68067] Wrong constant folding Date: Fri, 23 Oct 2015 09:35:00 -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: trans-mem X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: RESOLVED X-Bugzilla-Resolution: INVALID 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: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2015-10/txt/msg01931.txt.bz2 Content-length: 315 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68067 --- Comment #2 from Richard Biener --- Yep. Btw, what happens is that we see if (tem - 1 != 2147483647) and that is obviously always true unless tem - 1 wraps from -2147483648 to 2147483647 which would invoke undefined behavior.