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#12867: 24.3.50; easy-to-repro crash involving mode line Date: Mon, 12 Nov 2012 20:19:01 +0200 Message-ID: <83bof2wup6.fsf@gnu.org> References: <77CAAFE4D0CE4DD98476C996E3158648@us.oracle.com> <83obj2x218.fsf@gnu.org> <50A13289.4050301@gmx.at> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1352744386 5945 80.91.229.3 (12 Nov 2012 18:19:46 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 12 Nov 2012 18:19:46 +0000 (UTC) Cc: 12867@debbugs.gnu.org To: martin rudalics Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Mon Nov 12 19:19:56 2012 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 1TXyby-0005Xl-TY for geb-bug-gnu-emacs@m.gmane.org; Mon, 12 Nov 2012 19:19:55 +0100 Original-Received: from localhost ([::1]:45732 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TXybp-00053M-Bp for geb-bug-gnu-emacs@m.gmane.org; Mon, 12 Nov 2012 13:19:45 -0500 Original-Received: from eggs.gnu.org ([208.118.235.92]:51758) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TXybk-00051Z-DA for bug-gnu-emacs@gnu.org; Mon, 12 Nov 2012 13:19:43 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TXybh-0000Aa-BO for bug-gnu-emacs@gnu.org; Mon, 12 Nov 2012 13:19:40 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:53876) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TXybh-0000AW-7c for bug-gnu-emacs@gnu.org; Mon, 12 Nov 2012 13:19:37 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.72) (envelope-from ) id 1TXyc6-0007wF-DU for bug-gnu-emacs@gnu.org; Mon, 12 Nov 2012 13:20:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 12 Nov 2012 18:20:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 12867 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 12867-submit@debbugs.gnu.org id=B12867.135274437730480 (code B ref 12867); Mon, 12 Nov 2012 18:20:02 +0000 Original-Received: (at 12867) by debbugs.gnu.org; 12 Nov 2012 18:19:37 +0000 Original-Received: from localhost ([127.0.0.1]:35894 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TXybg-0007vZ-Tc for submit@debbugs.gnu.org; Mon, 12 Nov 2012 13:19:37 -0500 Original-Received: from mtaout20.012.net.il ([80.179.55.166]:51255) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TXybe-0007vR-Bm for 12867@debbugs.gnu.org; Mon, 12 Nov 2012 13:19:35 -0500 Original-Received: from conversion-daemon.a-mtaout20.012.net.il by a-mtaout20.012.net.il (HyperSendmail v2007.08) id <0MDE00L00059PJ00@a-mtaout20.012.net.il> for 12867@debbugs.gnu.org; Mon, 12 Nov 2012 20:18:46 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout20.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0MDE00LFG07ABDB0@a-mtaout20.012.net.il>; Mon, 12 Nov 2012 20:18:46 +0200 (IST) In-reply-to: <50A13289.4050301@gmx.at> X-012-Sender: halo1@inter.net.il X-Spam-Score: 1.5 (+) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.13 Precedence: list X-Spam-Score: 1.5 (+) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.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:66810 Archived-At: > Date: Mon, 12 Nov 2012 18:31:53 +0100 > From: martin rudalics > CC: Drew Adams , 12867@debbugs.gnu.org > > > The need to redisplay the mode line on every move of point is a killer > > of many redisplay optimizations. It is also potentially expensive by > > itself, because it requires Emacs to count lines, something that is > > not an easy operation in Emacs, which sees the buffer text as a linear > > array of characters, not a series of lines. So the display engine > > tries very hard to avoid redisplaying the mode line if it decides that > > the line number does not need to appear. > > I think it would make sense to use a cache for maintaining line numbers. We already do, but maybe not as extensively as you may have in mind. See the base_line_pos member of 'struct window'. There's also region-cache.c, which we could use for that. But before we do, Someone(TM) should time the thing and see if it's worth our while to make that cache.