From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#49261: Segfault during loadup Date: Wed, 14 Jul 2021 15:36:11 +0300 Message-ID: <83eec1843o.fsf@gnu.org> References: <87o8bn7bie.fsf@gnus.org> <87zgv6vuon.fsf@gmx.de> <837di9lwbm.fsf@gnu.org> <87a6n5vuu4.fsf@gnus.org> <8735sqnmei.fsf@gnus.org> <87zguyf4ht.fsf@gmx.de> <87pmvum54p.fsf@gnus.org> <87v95mf2lj.fsf@gmx.de> <87pmvt3ob1.fsf@gnus.org> <83r1g9evoy.fsf@gnu.org> <83pmvtevgg.fsf@gnu.org> <87czrt3mj4.fsf@gnus.org> <878s2h3m1d.fsf@gnus.org> <874kd53lnl.fsf@gnus.org> <87zgux26ab.fsf@gnus.org> <87pmvt25uq.fsf@gnus.org> <87lf6h2294.fsf@gnus.org> <87h7h51x9y.fsf_-_@gnus.org> <83bl79b17n.fsf@gnu.org> <835yxgc1pm.fsf@gnu.org> <83wnpvag6z.fsf@gnu.org> <5608bf0a-7211-73a9-690f-c869a1cb3c9d@cs.ucla.edu> <83o8b7a5ow.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="18277"; mail-complaints-to="usenet@ciao.gmane.io" Cc: larsi@gnus.org, 49261@debbugs.gnu.org To: Paul Eggert Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Wed Jul 14 14:37:26 2021 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1m3e8k-0004ZW-8D for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 14 Jul 2021 14:37:26 +0200 Original-Received: from localhost ([::1]:46134 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m3e8j-0004qe-4C for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 14 Jul 2021 08:37:25 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:44450) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m3e8N-0004NV-15 for bug-gnu-emacs@gnu.org; Wed, 14 Jul 2021 08:37:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:59972) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1m3e8M-0000b7-PL for bug-gnu-emacs@gnu.org; Wed, 14 Jul 2021 08:37:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1m3e8M-0005lo-GV for bug-gnu-emacs@gnu.org; Wed, 14 Jul 2021 08:37:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 14 Jul 2021 12:37:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 49261 X-GNU-PR-Package: emacs Original-Received: via spool by 49261-submit@debbugs.gnu.org id=B49261.162626621222158 (code B ref 49261); Wed, 14 Jul 2021 12:37:02 +0000 Original-Received: (at 49261) by debbugs.gnu.org; 14 Jul 2021 12:36:52 +0000 Original-Received: from localhost ([127.0.0.1]:43285 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1m3e8C-0005lK-Kl for submit@debbugs.gnu.org; Wed, 14 Jul 2021 08:36:52 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:46664) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1m3e8A-0005l1-LU for 49261@debbugs.gnu.org; Wed, 14 Jul 2021 08:36:51 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:38136) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m3e82-0000OX-Oo; Wed, 14 Jul 2021 08:36:43 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:1084 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m3e7Z-0002wb-RF; Wed, 14 Jul 2021 08:36:21 -0400 In-Reply-To: (message from Paul Eggert on Tue, 13 Jul 2021 18:12:00 -0500) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:209918 Archived-At: > Cc: larsi@gnus.org, 49261@debbugs.gnu.org > From: Paul Eggert > Date: Tue, 13 Jul 2021 18:12:00 -0500 > > On 7/12/21 10:54 AM, Eli Zaretskii wrote: > > Then what is the -Woverflow option for? Can you show an example of > > code which -Woverflow would flag that doesn't produce a bogus warning? > > Sure: the GCC documentation says -Woverflow is supposed to warn about > "compile-time overflow in constant expressions". So GCC should (and > does) warn about this top-level declaration: > > int x = INT_MAX + 1; > > However, there is no overflow here: > > unsigned a = -1, b = INT_MIN, c = LLONG_MAX; You are saying that there's some fundamental difference between INT_MAX + 1 and (USE_LSB_TAG ? - (1 << GCTYPEBITS) : VAL_MAX) ? Or between an expression 'x = FOO' and 'mask = BAR'? I don't see any fundamental difference. IMO, the warning was valid, as the assignment loses significant bits.