From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.bugs Subject: bug#21020: 24.4; `display-time-world' tampers with TZ Date: Mon, 27 Jul 2015 18:09:37 -0700 Organization: UCLA Computer Science Department Message-ID: <55B6D651.4070601@cs.ucla.edu> References: <55B487B4.7060709@cs.ucla.edu> <83vbd7yny9.fsf@gnu.org> <55B51362.2010301@cs.ucla.edu> <83lhe2zuu9.fsf@gnu.org> <55B51F1A.2000100@cs.ucla.edu> <83io96zsnj.fsf@gnu.org> <55B5399C.8040202@cs.ucla.edu> <83fv49zsuq.fsf@gnu.org> <83zj2hy0e0.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1438045825 6654 80.91.229.3 (28 Jul 2015 01:10:25 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 28 Jul 2015 01:10:25 +0000 (UTC) Cc: 21020@debbugs.gnu.org, wgg2@member.fsf.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Jul 28 03:10:13 2015 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZJtPH-00049S-Mz for geb-bug-gnu-emacs@m.gmane.org; Tue, 28 Jul 2015 03:10:11 +0200 Original-Received: from localhost ([::1]:56602 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZJtPH-0003LF-2p for geb-bug-gnu-emacs@m.gmane.org; Mon, 27 Jul 2015 21:10:11 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:57970) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZJtPC-0003IP-Np for bug-gnu-emacs@gnu.org; Mon, 27 Jul 2015 21:10:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZJtP9-0007LO-In for bug-gnu-emacs@gnu.org; Mon, 27 Jul 2015 21:10:06 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:59101) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZJtP9-0007LA-GD for bug-gnu-emacs@gnu.org; Mon, 27 Jul 2015 21:10:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1ZJtP9-0000zZ-4D for bug-gnu-emacs@gnu.org; Mon, 27 Jul 2015 21:10:03 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Paul Eggert Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 28 Jul 2015 01:10:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 21020 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: patch Original-Received: via spool by 21020-submit@debbugs.gnu.org id=B21020.14380457813782 (code B ref 21020); Tue, 28 Jul 2015 01:10:03 +0000 Original-Received: (at 21020) by debbugs.gnu.org; 28 Jul 2015 01:09:41 +0000 Original-Received: from localhost ([127.0.0.1]:60547 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1ZJtOn-0000yv-1k for submit@debbugs.gnu.org; Mon, 27 Jul 2015 21:09:41 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:43456) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1ZJtOl-0000yn-2D for 21020@debbugs.gnu.org; Mon, 27 Jul 2015 21:09:39 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 41748160CB6; Mon, 27 Jul 2015 18:09:38 -0700 (PDT) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id HuPQ61u4_U41; Mon, 27 Jul 2015 18:09:37 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 74020160CBA; Mon, 27 Jul 2015 18:09:37 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id vsoYkilOTdTi; Mon, 27 Jul 2015 18:09:37 -0700 (PDT) Original-Received: from [192.168.1.9] (pool-100-32-155-148.lsanca.fios.verizon.net [100.32.155.148]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 4D21C160CB6; Mon, 27 Jul 2015 18:09:37 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 In-Reply-To: <83zj2hy0e0.fsf@gnu.org> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 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.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:105176 Archived-At: Eli Zaretskii wrote: > I'm not even sure I > understand completely why this trick is needed (can you explain?). On many platforms, calling 'tzset' (either directly, or indirectly via localtime etc.) invalidates tzname[0] and tzname[1]. For example: time_t t = 0; char *p = tzname[0]; localtime (&t); puts (p ? p : "(null)"); Here 'puts' has undefined behavior if tzname[0] has been updated and its old value (equal to P) is no longer a valid pointer. lib/time_rz.c attempted to work around this problem by replacing tzname[0] and tzname[1] with pointers to more-stable copies. Apparently this doesn't work under MinGW. > can we please do this in some less intrusive way, e.g., by > copying the TZ names to our private storage? OK, I did that in master commit 2856b1dd6f0ff5164eb5a54ddfadb9963f9e9237.