From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Alp Aker Newsgroups: gmane.emacs.bugs Subject: bug#12745: crash in bidi_pop_it during (idle) redisplay Date: Mon, 29 Oct 2012 16:42:23 -0400 Message-ID: References: <508CA6FC.4070203@cs.ucla.edu> <508CE3B0.2030809@cs.ucla.edu> <83lieq8q91.fsf@gnu.org> <83fw4y8jgd.fsf@gnu.org> <838vap8aq8.fsf@gnu.org> <837gq987yv.fsf@gnu.org> <83390x81ql.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1351543364 13016 80.91.229.3 (29 Oct 2012 20:42:44 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 29 Oct 2012 20:42:44 +0000 (UTC) Cc: 12745@debbugs.gnu.org, ami@fischman.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Mon Oct 29 21:42:52 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 1TSwAZ-0008AM-Oc for geb-bug-gnu-emacs@m.gmane.org; Mon, 29 Oct 2012 21:42:47 +0100 Original-Received: from localhost ([::1]:52605 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TSwAR-0001iQ-Ht for geb-bug-gnu-emacs@m.gmane.org; Mon, 29 Oct 2012 16:42:39 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:54092) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TSwAO-0001iK-Pl for bug-gnu-emacs@gnu.org; Mon, 29 Oct 2012 16:42:37 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TSwAN-0007Px-HN for bug-gnu-emacs@gnu.org; Mon, 29 Oct 2012 16:42:36 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:56540) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TSwAN-0007Po-EP for bug-gnu-emacs@gnu.org; Mon, 29 Oct 2012 16:42:35 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.72) (envelope-from ) id 1TSwCk-0004HW-IG for bug-gnu-emacs@gnu.org; Mon, 29 Oct 2012 16:45:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alp Aker Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 29 Oct 2012 20:45:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 12745 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 12745-submit@debbugs.gnu.org id=B12745.135154349516431 (code B ref 12745); Mon, 29 Oct 2012 20:45:02 +0000 Original-Received: (at 12745) by debbugs.gnu.org; 29 Oct 2012 20:44:55 +0000 Original-Received: from localhost ([127.0.0.1]:38558 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TSwCc-0004Gx-Pf for submit@debbugs.gnu.org; Mon, 29 Oct 2012 16:44:55 -0400 Original-Received: from mail-ie0-f172.google.com ([209.85.223.172]:33461) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TSwCZ-0004Gp-UT for 12745@debbugs.gnu.org; Mon, 29 Oct 2012 16:44:53 -0400 Original-Received: by mail-ie0-f172.google.com with SMTP id 9so7350645iec.3 for <12745@debbugs.gnu.org>; Mon, 29 Oct 2012 13:42:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=Nm0dHEculQgaxW5122jd/FKyVUMoSU7rSs1ffS4x8eg=; b=hWMDx9hU5dKhLLL2bzIMBj9/YAloLUG2zGNa5+d1oJTBmnZZibdXqlV6xwW0StdZaE gUDOvEs0ZtawvBIjg9pCzcMMeV4c2eK5O/JtEsgrE2mEuauz2jY2xkHJ69Gv9PJk+dxI us+wdZk49XGFBc7IBHSssyptz5EQ9fxGpJP4RBm03JoHlq+PAIu9L1c9DcgpRP7RRE+W NANYdgtEVQNsE9pKXfqM9Qdh4iZLzWJ4/Svoplyc0axfpo5T+nT/NrYRsCXO7VNlU41C SO7HJwvL8lH6DbgbA7TV6T1jjcUWYDaUGdYXhj0qBLG2utItK45kPPqwpHUU1oEO301K 2xJw== Original-Received: by 10.50.202.104 with SMTP id kh8mr10683942igc.21.1351543343608; Mon, 29 Oct 2012 13:42:23 -0700 (PDT) Original-Received: by 10.64.53.132 with HTTP; Mon, 29 Oct 2012 13:42:23 -0700 (PDT) In-Reply-To: <83390x81ql.fsf@gnu.org> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.13 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) 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:66213 Archived-At: > Out of curiosity: what is the purpose of having in an overlay this > weird character and then to display it as a space? It's a hack to achieve compatibility with packages that change the display table entry for the newline character. When fci-mode is active it puts, at the end of each line, a stretch glyph and then an image with the line segment indicating the fill column. When, e.g., whitespace-mode changes the display table entry for newlines to display a '$' at the end of the line, this would show up *after* the stretch glyph and image unless we do something to handle that case. So what fci-mode tries to do is intercept changes to the display table entry for newlines. If something like whitespace mode changes newline display, fci-mode changes the display table back to showing newlines as blanks, and then updates the display table entry for U+E000 to (in this case) [?$], so that the end-of-line indication appears where the user expects it to be. So the weird character is just a hook on which we can hang display vectors intended for newlines. But when the display settings for newlines are normal it just gets displayed as a space. This is admittedly a gross manoeuvre, but I couldn't think of any other way to handle the issue.