From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: martin rudalics Newsgroups: gmane.emacs.bugs Subject: bug#39977: 28.0.50; Unhelpful stack trace Date: Wed, 18 Mar 2020 10:12:32 +0100 Message-ID: <90ac4084-4fbb-b5d7-6a7c-597d8f08e88a@gmx.at> References: <83zhcs80e5.fsf@gnu.org> <83imj88tpt.fsf@gnu.org> <550fbc22-09db-d30b-c194-8f26b5dca05f@gmx.at> <83wo7o6nxs.fsf@gnu.org> <60dd4ced-a2e5-ed17-0570-b7bdd2a557af@gmx.at> <83blozckn2.fsf@gnu.org> <01305dbc-c69b-baf9-f0bf-1e5b8c04d970@gmx.at> <83y2s2bswl.fsf@gnu.org> <3ac189d0-5d05-fdf9-0922-0c464b1b17c3@gmx.at> <83k13lbgux.fsf@gnu.org> <83d09cb9gz.fsf@gnu.org> <69a74f9e-079b-a771-0213-f60ed0bf5720@gmx.at> <83y2rzf08m.fsf@gnu.org> <7a0b9999-6778-6235-fbc9-2a24b4e3bc53@gmx.at> <83tv2mg9j0.fsf@gnu.org> <9684641c-a59a-4ed6-a6b4-d3238f789050@gmx.at> <83sgi6g461.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="124832"; mail-complaints-to="usenet@ciao.gmane.io" Cc: enometh@meer.net, 39977@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Wed Mar 18 10:13:40 2020 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jEUlf-000WKI-UR for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 18 Mar 2020 10:13:40 +0100 Original-Received: from localhost ([::1]:47376 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jEUle-0002bT-BY for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 18 Mar 2020 05:13:38 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:37392) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jEUl5-0002bL-9L for bug-gnu-emacs@gnu.org; Wed, 18 Mar 2020 05:13:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jEUl4-0002jX-3W for bug-gnu-emacs@gnu.org; Wed, 18 Mar 2020 05:13:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:33838) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1jEUl3-0002ir-VT for bug-gnu-emacs@gnu.org; Wed, 18 Mar 2020 05:13:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jEUl3-0006WO-Nn for bug-gnu-emacs@gnu.org; Wed, 18 Mar 2020 05:13:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: martin rudalics Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 18 Mar 2020 09:13:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 39977 X-GNU-PR-Package: emacs Original-Received: via spool by 39977-submit@debbugs.gnu.org id=B39977.158452276825049 (code B ref 39977); Wed, 18 Mar 2020 09:13:01 +0000 Original-Received: (at 39977) by debbugs.gnu.org; 18 Mar 2020 09:12:48 +0000 Original-Received: from localhost ([127.0.0.1]:39811 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jEUkq-0006Vx-AB for submit@debbugs.gnu.org; Wed, 18 Mar 2020 05:12:48 -0400 Original-Received: from mout.gmx.net ([212.227.17.22]:58071) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jEUko-0006Vj-5b for 39977@debbugs.gnu.org; Wed, 18 Mar 2020 05:12:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1584522755; bh=9y8VQsQt1UZHRpirJCS9O8DWtPw+1pgfOGSi9232//U=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=Nrapo7YFZD/gtw6sq/Cz7PddjQ8/6Hl9CDJ+hWMysHryNP4OEAij4YijdyAP0lMbk UnsfkyXyrnmfvw712oRIjpBoFr/qKKX2gw++KFpTG5XXmVF8FiiudUAhTzY42BKQG7 nL0tK60TyMyIn71nSnA0u0hKlAw3JJaCgNCavScM= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Original-Received: from [192.168.1.101] ([46.125.249.17]) by mail.gmx.com (mrgmx104 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MulqN-1jWA7s03mN-00rmEs; Wed, 18 Mar 2020 10:12:35 +0100 In-Reply-To: <83sgi6g461.fsf@gnu.org> Content-Language: en-US X-Provags-ID: V03:K1:f8XndkMGsPynl0oX6/sXkbAtLKnXqehod658U0anviCazO6DOnw pmK0/5xg0KIfIXy/02Gcsy+LP5vW58+mQj76ySCOMhuNk0TQ5VIQGaKQ2JKlXPdugWcv8mn AimXvZuOJNQIp4vHdhLnMtAsTrKXsVTPJfZBvFx8C4Twgo6AX8Qch6pVma65xVGWobWVE99 7+nIHkupZdwbYiDrsjiZw== X-UI-Out-Filterresults: notjunk:1;V03:K0:qQlSO7CcvII=:ovR//lbRtREJn0IP26JCdX LrAB3FqIYKmSDmc1YWlfTE31lDfduJDsz90veejeFIge83aFIFpLqBgSRydf2iCUQebYh+B1m uobGwCdSlj6EuYl97zWAeqUJwJTXRspN5gsFzmnFnrK4grgxDC53OHQdlvTYM5YPRvDJr51/2 L9aJvKy25KqZNTn8Y4yYP+NzYV4iQsQuaqIsGWkIA5IJd6u2QLqbFPYxTcTrJ4Na95kILZdbq +mgzbHGrI0DYEwEKzxSdQuXlrs8KVGK3fEAbfEh3VZeqIHCp1OMAoq7qJ7afwe0M53W1VroAA iYP4oy/g93rm1ZAA4UHpMui7NE/tXGnMX9n5v0vozsZLVLPzZh4cqzTG9O3u1i1unLkceQp+p x6TqIWKMhHSJgoCMcBEh+ZFBNQOwfRjMxKUEPlsm+5EgvNmhx8quKWMu0iA9YyqTbVJpXuvlF 7ThWf2tfNvn/6QOeu7PICyaNwsfoGkIS4A/5pBKpPsOU6mfericvbFbv5O3FgpbOzVSuaKCtz ZA58gyKE+D+Y3ok3Btw6GQSER+6KOYcekGJMfl8bZ2QcrYNEx7qkS7oyFMjum3qj2ivAnv2Y4 qvLJAY/rHyfJY7IiUWW2vVYDYBSKrW28gvrr8rzdSQTBpUQ50qGvs1n+ef6Fm9krWfkwSDbdu 0jTYS3cqgl2PUEv+wiYAFNlWSKvMaMx6v/8tWj5WypUzgdzII8qSzzSqzjImBnwWJhHIOB8V3 6lgvp6TNXSZCpS25W/cI4kMDzHsJrMbyX2qEQLd8VFaiFfah3oX/1+4uEHvBvbW46SN35GqN 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-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:177479 Archived-At: > I'm sorry, I think I no longer know what we are discussing. For me the present abort is just another instance of Bug#29726 where you said: The reason for the crash is that the ':eval' form which you have on the header-line can delete the frame whose header-line Emacs is redrawing! The Lisp-level backtrace below shows how delete-frame is called from your code; hopefully, this backtrace will allow you to fix your code so it doesn't do such nonsensical things. Only that in the case at hand 'delete-frame' does not try to delete the frame the display engine is working on and so your fix for Bug#29726 won't catch it. Rather, the frame that gets deleted is the frame that was selected before the display engine started to process the :eval form. When, after processing the :eval form and the containing mode line or title bar format, the display engine wants to restore the previously selected frame, it sets selected_frame to a dead frame. And the next attempt to use selected_frame via SELECTED_FRAME results in the abort. > Feel free > to fix this (whatever it is) as you see fit. The longer I'm looking into this, the more I think that we should be much more restrictive wrt what an :eval form in mode line or title name processing should be allowed to do. Tab bars could provide even more confusion. I think we should disallow any such :eval to kill buffers and delete windows or frames at the very least. Maybe it should be also disallowed to select a window or frame or whatever the display engine tries to restore after processing these forms. Such selections would be usually undone anyway by the display engine. Probably, we should disallow such :eval forms to modify "anything" at all but I have no idea how to do that. martin