From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Juri Linkov Newsgroups: gmane.emacs.bugs Subject: bug#38049: C mode fontification broken with reposition-window Date: Wed, 06 Nov 2019 00:10:29 +0200 Organization: LINKOV.NET Message-ID: <87lfsu9e6a.fsf@mail.linkov.net> References: <8736f4k8mi.fsf@mail.linkov.net> <20191105210737.GA6303@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="42356"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (x86_64-pc-linux-gnu) Cc: 38049@debbugs.gnu.org To: Alan Mackenzie Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Nov 05 23:59:29 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 1iS7nN-000Aom-9I for geb-bug-gnu-emacs@m.gmane.org; Tue, 05 Nov 2019 23:59:29 +0100 Original-Received: from localhost ([::1]:51326 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iS7nL-0007YC-Pv for geb-bug-gnu-emacs@m.gmane.org; Tue, 05 Nov 2019 17:59:27 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:33518) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iS7my-00079Q-MR for bug-gnu-emacs@gnu.org; Tue, 05 Nov 2019 17:59:05 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iS7mx-0002Le-M6 for bug-gnu-emacs@gnu.org; Tue, 05 Nov 2019 17:59:04 -0500 Original-Received: from debbugs.gnu.org ([209.51.188.43]:58602) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1iS7mx-0002LW-IX; Tue, 05 Nov 2019 17:59:03 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1iS7mx-0004yG-HD; Tue, 05 Nov 2019 17:59:03 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Juri Linkov Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org, bug-cc-mode@gnu.org Resent-Date: Tue, 05 Nov 2019 22:59:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 38049 X-GNU-PR-Package: emacs,cc-mode Original-Received: via spool by 38049-submit@debbugs.gnu.org id=B38049.157299470118974 (code B ref 38049); Tue, 05 Nov 2019 22:59:03 +0000 Original-Received: (at 38049) by debbugs.gnu.org; 5 Nov 2019 22:58:21 +0000 Original-Received: from localhost ([127.0.0.1]:39176 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1iS7mH-0004vy-7y for submit@debbugs.gnu.org; Tue, 05 Nov 2019 17:58:21 -0500 Original-Received: from dog.birch.relay.mailchannels.net ([23.83.209.48]:3152) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1iS7mE-0004vk-IE for 38049@debbugs.gnu.org; Tue, 05 Nov 2019 17:58:19 -0500 X-Sender-Id: dreamhost|x-authsender|jurta@jurta.org Original-Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id 20AE15006E0; Tue, 5 Nov 2019 22:58:17 +0000 (UTC) Original-Received: from pdx1-sub0-mail-a64.g.dreamhost.com (100-96-60-110.trex.outbound.svc.cluster.local [100.96.60.110]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id A19F950086B; Tue, 5 Nov 2019 22:58:16 +0000 (UTC) X-Sender-Id: dreamhost|x-authsender|jurta@jurta.org Original-Received: from pdx1-sub0-mail-a64.g.dreamhost.com ([TEMPUNAVAIL]. [64.90.62.162]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384) by 0.0.0.0:2500 (trex/5.18.5); Tue, 05 Nov 2019 22:58:17 +0000 X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|jurta@jurta.org X-MailChannels-Auth-Id: dreamhost X-Little-Shade: 45495efa7ffa7de8_1572994696893_3919433319 X-MC-Loop-Signature: 1572994696893:345676443 X-MC-Ingress-Time: 1572994696893 Original-Received: from pdx1-sub0-mail-a64.g.dreamhost.com (localhost [127.0.0.1]) by pdx1-sub0-mail-a64.g.dreamhost.com (Postfix) with ESMTP id 24BEE7F51E; Tue, 5 Nov 2019 14:58:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=linkov.net; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=linkov.net; bh=X0l+SXfdqOVVP+Wmxv16SPe3988=; b= Akcz0wC7w8VyqrkJvX3uymEvCQIrFCLFTswPzChguLm5jHCDCtBTXUFYpxvjJqSe 7SftJBg5vWljiFCqoVsDSpLZ1IY/4cG30XKrWLVSyE+TCLbVqvsGUfr7LdfC3Px1 0c0yGDu3/s+hqa62px2daXGz+m593SmnhbKqPg8vGz4= Original-Received: from mail.jurta.org (m91-129-101-77.cust.tele2.ee [91.129.101.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: jurta@jurta.org) by pdx1-sub0-mail-a64.g.dreamhost.com (Postfix) with ESMTPSA id 49F667F512; Tue, 5 Nov 2019 14:58:08 -0800 (PST) X-DH-BACKEND: pdx1-sub0-mail-a64 In-Reply-To: <20191105210737.GA6303@ACM> (Alan Mackenzie's message of "Tue, 5 Nov 2019 21:07:37 +0000") 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:170992 Archived-At: > Briefly, > (i) reposition-window narrows to (2758 3940) in > repos-count-screen-lines. > (ii) This latter function uses vertical-motion to count the lines. > (iii) vertical-motion triggers jit-lock fontification. > (iv) This calls (eventually) c-font-lock-fontify-region. > (v) c-font-lock-fontify-region attempts to examine buffer text before > the start of the jit-lock chunk to find syntactic context. > (vi) This is outside the visible region, so Emacs raises an exception. > (vii) The exception is caught and discarded by an unwind-protect in > c-font-lock-fontify-region. > (viii) The jit-lock chunk remains unfontified. > > As Stefan M has sometimes remarked, narrowing is often not a good idea. > > It would seem undesirable for the vertical-motion in (iii) to trigger > font-locking, since it is merely trying to count lines. Perhaps there > should be a macro `without-fontifying' which could be wrapped around > this call to vertical-motion, if there isn't such a thing anyway. ISTR there was some macro to disable font-lock temporarily, but I can't find it. Maybe just let-binding font-lock-mode to nil could help?