From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: My Emacs unicode 2 crash again when I do some *Replace String (M-%)*, I give the debug informations under gdb in the attachments. Date: Tue, 13 Mar 2007 08:54:09 +0100 Message-ID: <864pop1sv2.fsf@lola.quinscape.zz> References: <20070306063056.GA21948@debian-testing-hy.localdomain> <86zm6q5upr.fsf@lola.quinscape.zz> <17902.9556.720278.162036@kahikatea.snap.net.nz> <85bqizpiu6.fsf@lola.goethe.zz> <871wjvc7or.fsf@uwakimon.sk.tsukuba.ac.jp> <87odmxbyrx.fsf@uwakimon.sk.tsukuba.ac.jp> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1173772501 16632 80.91.229.12 (13 Mar 2007 07:55:01 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 13 Mar 2007 07:55:01 +0000 (UTC) Cc: Eli Zaretskii , emacs-devel@gnu.org To: "Stephen J. Turnbull" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Mar 13 08:54:54 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1HR1qO-00007W-68 for ged-emacs-devel@m.gmane.org; Tue, 13 Mar 2007 08:54:53 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HR1r6-0007m5-SN for ged-emacs-devel@m.gmane.org; Tue, 13 Mar 2007 02:55:36 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HR1qg-0007jN-8k for emacs-devel@gnu.org; Tue, 13 Mar 2007 03:55:10 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HR1qe-0007hx-L4 for emacs-devel@gnu.org; Tue, 13 Mar 2007 03:55:09 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HR1qe-0007hu-DZ for emacs-devel@gnu.org; Tue, 13 Mar 2007 02:55:08 -0500 Original-Received: from pc3.berlin.powerweb.de ([62.67.228.11]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1HR1ps-0006WG-3o for emacs-devel@gnu.org; Tue, 13 Mar 2007 03:54:21 -0400 Original-Received: from quinscape.de (pd95b0fdb.dip0.t-ipconnect.de [217.91.15.219]) by pc3.berlin.powerweb.de (8.9.3p3/8.9.3) with ESMTP id IAA05536 for ; Tue, 13 Mar 2007 08:54:08 +0100 X-Delivered-To: Original-Received: (qmail 8148 invoked from network); 13 Mar 2007 07:54:14 -0000 Original-Received: from unknown (HELO lola.quinscape.zz) ([10.0.3.43]) (envelope-sender ) by ns.quinscape.de (qmail-ldap-1.03) with SMTP for ; 13 Mar 2007 07:54:14 -0000 Original-Received: by lola.quinscape.zz (Postfix, from userid 1001) id 48C36DAEDF; Tue, 13 Mar 2007 08:54:09 +0100 (CET) In-Reply-To: <87odmxbyrx.fsf@uwakimon.sk.tsukuba.ac.jp> (Stephen J. Turnbull's message of "Tue\, 13 Mar 2007 12\:36\:18 +0900") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (gnu/linux) X-detected-kernel: Linux 2.4-2.6 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:67847 Archived-At: "Stephen J. Turnbull" writes: > Eli Zaretskii writes: > > > The problem is, again, that the list of -fxxx options that, if > > disabled, will make the program much easier to debug, is not known > > We already have one (-fno-cross-jumps or similar). Others can be > added as people find out about them. I'm simply saying that this > information should be available to *all* Emacs developers (eg, by > configuring with --marquis-de-sade-optimizations=no-thank-you), not > just to those who happen to read every post David makes. I've written this info into the file etc/DEBUG, too, but it would be overoptimistic to assume that everybody reads that before starting out. I actually know no option with similarly devastating effects on debugging productivity: if registers and values and stuff get optimized away, that is basically a nuisance, but gdb tells you what happens (at least with newer debug info formats, which value is where is traced rather well). I just fine-combed the other gcc options and did not detect any option which would have the effect of leading the debugging person to a completely wrong place: other stuff may make debugging more adventurous, but as far as I can see, it will not cause plausible lies from the debugger. The crossjumps option ruins post-mortem debugging by very convincingly making the backtrace point to the wrong failed assertion. It does not help to put a breakpoint on "abort" either. It cost me several days of debugging once. > > So I don't think we know what to put in aclocal. Well, not using -fno-crossjumping cost me several days of debugging, it made me put the info in etc/DEBUG, and it cost another person a few days before I again volunteered this information. How much more wasted man-hours do you want, Eli, before "knowing" it might be a good idea to use this by default? Debugging failed assertions is not exactly a rare occurence. I'd say what is good enough for etc/DEBUG is good enough for aclocal. Of course, we'll need an autoconf check that this option is actually supported by the gcc version in question. -- David Kastrup