From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Crash robustness (Was: Re: Dynamic modules: MODULE_HANDLE_SIGNALS etc.) Date: Wed, 23 Dec 2015 19:55:17 +0200 Message-ID: <8360zpoxru.fsf@gnu.org> References: <83mvu1x6t3.fsf@gnu.org> <565779CD.80405@cs.ucla.edu> <83io4nuc68.fsf@gnu.org> <83r3iht93x.fsf@gnu.org> <838u4psznr.fsf@gnu.org> <56772054.8010401@cs.ucla.edu> <83zix4scgf.fsf@gnu.org> <5677DBC9.6030307@cs.ucla.edu> <83io3rst2r.fsf@gnu.org> <567841A6.4090408@cs.ucla.edu> <567844B9.2050308@dancol.org> <5678CD07.8080209@cs.ucla.edu> <5678D3AF.7030101@dancol.org> <83oadiqxq1.fsf@gnu.org> <5679B33E.9000804@dancol.org> <83y4cmp5y5.fsf@gnu.org> <5679B7F5.9030504@dancol.org> <83twnap4xa.fsf@gnu.org> <5679BE1D.5070903@dancol.org> <83poxxp2rl.fsf@gnu.org> <567ACB0F.9060804@dancol.org> <83a8p1oyxc.fsf@gnu.org> <567ADCC0.6090709@dancol.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1450893297 512 80.91.229.3 (23 Dec 2015 17:54:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 23 Dec 2015 17:54:57 +0000 (UTC) Cc: aurelien.aptel+emacs@gmail.com, p.stephani2@gmail.com, eggert@cs.ucla.edu, tzz@lifelogs.com, emacs-devel@gnu.org To: Daniel Colascione Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Dec 23 18:54:51 2015 Return-path: Envelope-to: ged-emacs-devel@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 1aBncf-0002gJ-Mc for ged-emacs-devel@m.gmane.org; Wed, 23 Dec 2015 18:54:49 +0100 Original-Received: from localhost ([::1]:57274 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBncf-000576-34 for ged-emacs-devel@m.gmane.org; Wed, 23 Dec 2015 12:54:49 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:45510) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBncb-00056r-IF for emacs-devel@gnu.org; Wed, 23 Dec 2015 12:54:46 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aBncY-0003yz-A4 for emacs-devel@gnu.org; Wed, 23 Dec 2015 12:54:45 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:59345) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBncY-0003yv-6Y; Wed, 23 Dec 2015 12:54:42 -0500 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:2313 helo=HOME-C4E4A596F7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1aBncX-00083n-94; Wed, 23 Dec 2015 12:54:41 -0500 In-reply-to: <567ADCC0.6090709@dancol.org> (message from Daniel Colascione on Wed, 23 Dec 2015 09:41:20 -0800) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:196729 Archived-At: > Cc: eggert@cs.ucla.edu, aurelien.aptel+emacs@gmail.com, > p.stephani2@gmail.com, tzz@lifelogs.com, emacs-devel@gnu.org > From: Daniel Colascione > Date: Wed, 23 Dec 2015 09:41:20 -0800 > > > We could try calling shut_down_emacs from the signal handler, but I'm > > not sure if the small alternate stack will be enough for write-region. > > Something to investigate, I guess. > > We can make the alternate signal stack as large as we want. Not as large as is safe to run arbitrary Lisp. > >> The next time Emacs starts, we can restore the buffers we've saved > >> this way and ask users to save them --- just like autosave, but done > >> on-demand, at crash time, in C code, on the alternate signal stack. > > > > Why "like autosave"? What will be different from actually > > auto-saving? shut_down_emacs does that automatically. > > > > Er, yes, I noticed that after I wrote the email that we already do what > I propose, more or less. In this case, we don't lose very much by just > deleting the stack overflow code and relying on autosave. Auto-save will only save buffers that visit files.