From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#16901: 24.3.50; emacs_backtrace.txt Date: Tue, 04 Mar 2014 19:37:15 +0200 Message-ID: <8361ntsw50.fsf@gnu.org> References: <831tylvkq2.fsf@gnu.org> <83lhwstu1k.fsf@gnu.org> <83ppm3rznz.fsf@gnu.org> <53150E29.7080504@cornell.edu> <83iorusk3h.fsf@gnu.org> <5315E1EB.8060404@cornell.edu> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1393954694 12977 80.91.229.3 (4 Mar 2014 17:38:14 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 4 Mar 2014 17:38:14 +0000 (UTC) Cc: 16901@debbugs.gnu.org, lekktu@gmail.com, dmantipov@yandex.ru To: Ken Brown Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Mar 04 18:38:21 2014 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 1WKtIL-0002oU-2n for geb-bug-gnu-emacs@m.gmane.org; Tue, 04 Mar 2014 18:38:21 +0100 Original-Received: from localhost ([::1]:47033 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WKtIK-0004Vn-O1 for geb-bug-gnu-emacs@m.gmane.org; Tue, 04 Mar 2014 12:38:20 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:41762) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WKtIC-0004Ol-1Q for bug-gnu-emacs@gnu.org; Tue, 04 Mar 2014 12:38:17 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WKtI3-0004wh-66 for bug-gnu-emacs@gnu.org; Tue, 04 Mar 2014 12:38:11 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:49396) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WKtI3-0004wb-3c for bug-gnu-emacs@gnu.org; Tue, 04 Mar 2014 12:38:03 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WKtI2-0001fw-5V for bug-gnu-emacs@gnu.org; Tue, 04 Mar 2014 12:38:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 04 Mar 2014 17:38:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 16901 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: moreinfo Original-Received: via spool by 16901-submit@debbugs.gnu.org id=B16901.13939546546385 (code B ref 16901); Tue, 04 Mar 2014 17:38:02 +0000 Original-Received: (at 16901) by debbugs.gnu.org; 4 Mar 2014 17:37:34 +0000 Original-Received: from localhost ([127.0.0.1]:50578 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WKtHY-0001er-90 for submit@debbugs.gnu.org; Tue, 04 Mar 2014 12:37:32 -0500 Original-Received: from mtaout23.012.net.il ([80.179.55.175]:59713) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WKtHU-0001eh-2L for 16901@debbugs.gnu.org; Tue, 04 Mar 2014 12:37:29 -0500 Original-Received: from conversion-daemon.a-mtaout23.012.net.il by a-mtaout23.012.net.il (HyperSendmail v2007.08) id <0N1X00J009T19D00@a-mtaout23.012.net.il> for 16901@debbugs.gnu.org; Tue, 04 Mar 2014 19:37:26 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout23.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0N1X00JOPAAE8K30@a-mtaout23.012.net.il>; Tue, 04 Mar 2014 19:37:26 +0200 (IST) In-reply-to: <5315E1EB.8060404@cornell.edu> X-012-Sender: halo1@inter.net.il 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:86542 Archived-At: > Date: Tue, 04 Mar 2014 09:23:39 -0500 > From: Ken Brown > CC: lekktu@gmail.com, 16901@debbugs.gnu.org, dmantipov@yandex.ru > > On 3/3/2014 10:45 PM, Eli Zaretskii wrote: > >> Date: Mon, 03 Mar 2014 18:20:09 -0500 > >> From: Ken Brown > >> CC: 16901@debbugs.gnu.org, dmantipov@yandex.ru > >> > >> If adj == 0 in line 1596, then we've allocated much more memory than > >> we needed, and the next call to malloc (line 1602) allocates even > >> more. And if adj == 1 in line 1596, then we've allocated exactly as > >> much memory as we needed, so there's no need to call malloc again in > >> line 1602. > > > > Thanks for reviewing. > > > > These are further optimizations, and can (and probably should) be done > > in separate commits. Now done in trunk revision 16661. > > But you aren't saying that the previous code was correct, are you? > > No, I think it was clearly wrong. By accident, however, it probably > worked most of the time and didn't waste memory, since adj is usually 0. Yes, when the initial allocation was already aligned, it worked OK. > When/if you do the optimizations I suggested, I think it would clarify > the code if `adj' were used to represent the actual adjustment needed, > something like this: > > adj = (uintptr_t) alignment - result % alignment; > if (adj == alignment) > adj = 0; I didn't make this change, but feel free to follow up. Thanks.