From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Kangas Newsgroups: gmane.emacs.bugs Subject: bug#11545: 24.0.96-mac-2.92; Strange speed problem scrolling in C++ code Date: Fri, 01 Nov 2019 19:40:31 +0100 Message-ID: <87bltvigo0.fsf@skangas.se> References: <20120602212028.GA8233@acm.acm> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="255094"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: John Wiegley , 11545@debbugs.gnu.org To: Alan Mackenzie Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Fri Nov 01 19:41:17 2019 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iQbrI-0014El-Dx for geb-bug-gnu-emacs@m.gmane.org; Fri, 01 Nov 2019 19:41:16 +0100 Original-Received: from localhost ([::1]:42094 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQbrG-00006I-Lb for geb-bug-gnu-emacs@m.gmane.org; Fri, 01 Nov 2019 14:41:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:52948) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQbrA-00006B-5N for bug-gnu-emacs@gnu.org; Fri, 01 Nov 2019 14:41:09 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iQbr8-0002bo-VG for bug-gnu-emacs@gnu.org; Fri, 01 Nov 2019 14:41:08 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:48304) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1iQbr4-0002ZY-Ok; Fri, 01 Nov 2019 14:41:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1iQbr4-0002iL-H2; Fri, 01 Nov 2019 14:41:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Kangas Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org, bug-cc-mode@gnu.org Resent-Date: Fri, 01 Nov 2019 18:41:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 11545 X-GNU-PR-Package: emacs,cc-mode Original-Received: via spool by 11545-submit@debbugs.gnu.org id=B11545.157263364410390 (code B ref 11545); Fri, 01 Nov 2019 18:41:02 +0000 Original-Received: (at 11545) by debbugs.gnu.org; 1 Nov 2019 18:40:44 +0000 Original-Received: from localhost ([127.0.0.1]:57125 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1iQbqm-0002hW-DB for submit@debbugs.gnu.org; Fri, 01 Nov 2019 14:40:44 -0400 Original-Received: from host.gofardesign.uk ([208.79.239.190]:32776) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1iQbqj-0002hI-UI for 11545@debbugs.gnu.org; Fri, 01 Nov 2019 14:40:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=marxist.se; s=default; h=Content-Type:MIME-Version:Message-ID:Date:References: In-Reply-To:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=t5kAl5NXVp6fETMiasP5GqdldNSJ9LKA3p62+il3WL0=; b=UQp2suqmQQs9+EtxJX0wy/TmcX KAtXx/h6tM3wlT6WdirdFKKREAj9aAj0ETyGyT+5IrzhnXnGCoiboYeBP4RyvVESP6EJ4vaDkjQ7b C3HXkm7z1CFW5NBGN2wGDrh2vzurbTyPDuztGD15AVQTvBtpjM8KiHIzfectYPvtO4aU=; Original-Received: from h-70-69.a785.priv.bahnhof.se ([155.4.70.69]:46824 helo=localhost) by host.gofardesign.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92) (envelope-from ) id 1iQbqb-0003nS-LX; Fri, 01 Nov 2019 13:40:34 -0500 In-Reply-To: <20120602212028.GA8233@acm.acm> (Alan Mackenzie's message of "Sat, 2 Jun 2012 21:20:28 +0000") X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - host.gofardesign.uk X-AntiAbuse: Original Domain - debbugs.gnu.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - marxist.se X-Get-Message-Sender-Via: host.gofardesign.uk: authenticated_id: stefan@marxist.se X-Authenticated-Sender: host.gofardesign.uk: stefan@marxist.se X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.51.188.43 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" Xref: news.gmane.org gmane.emacs.bugs:170654 Archived-At: Hi Alan, Alan Mackenzie writes: > On Mon, May 28, 2012 at 06:05:15PM -0500, John Wiegley wrote: >> >>>>> John Wiegley writes: > >> >>>>>> YAMAMOTO Mitsuharu writes: >> >> With the Time Profiler in Instrument.app, I found that fontification >> >> of CC Mode in Emacs 24 is much heavier and causes frequent GCs than >> >> that in Emacs 23. Please try the following: > >> >> 1. Start Emacs 24 Mac port with -Q (alternatively, pressing the >> >> shift key.) >> >> 2. M-x load-file PREFIX/share/emacs/23.4/lisp/progmodes/cc-fonts.elc >> >> RTE. >> >> 3. Replay scrolling a large C++ file. > >> >> I'm not sure if this slowdown is intended or expected. > >> > Indeed, this makes the speed situation much better on Emacs 24.0.97. > >> I can now confirm that loading CC-Mode 5.32.3 into Emacs 23.4 causes >> the identical speed issues that I was seeing with Emacs 24.0.97, so >> this is a performance issue in the latest CC-Mode, not a bug in Emacs >> 24 or with Mac-Port Emacs. > >> To the CC-Mode maintainers: is there a way to disable the slower, "more >> correct" mode in the latest CC-Mode, and go back to the entirely >> sufficient (for me) mode of previous versions? > > Not as such, no. The only workaround at the moment is to use a > "pre-correct" version of CC Mode in place of an up to date one. > > I've just done a binary chop on CC Mode versions, and it seems the latest > version before (?the first of) these enhancements was the one created by > this (mercurial) changeset (the repository can be downloaded from > ): > > changeset: 5109:981fa4f0270c > parent: 5107:bd4013c5633b > user: acmacm > date: Wed Sep 15 17:47:52 2010 +0000 > files: cc-engine.el > description: > (c-forward-<>-arglist-recur): Fix an infinite recursion. > > To undo these changes would be difficult, since several later > enhancements and bug fixes are based on the new code. I'll see if I can > find some way of optimising the offending code - most of the time it's > doing expensive checks and finding nothing. > > Anyhow, I've got the problem flagged as a bug now. Thanks again for > reporting it. Just to follow up on this bug, which has seen no update in the last 7 years. Has it been fixed by now? Best regards, Stefan Kangas