From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Nikolay Kudryavtsev Newsgroups: gmane.emacs.devel Subject: Re: Unexec dumping results in "Segmentation fault" on Windows Msys2 Date: Thu, 29 Apr 2021 22:17:10 +0300 Message-ID: References: <83im52ed8b.fsf@gnu.org> <989be2e0-a090-309b-58cb-8064c6bd5aee@gmail.com> <83y2dycmgr.fsf@gnu.org> <835z0oyrct.fsf@gnu.org> <83eefby1hy.fsf@gnu.org> <64f14133-a647-7406-4908-671258038ae2@gmail.com> <834kg7xqrm.fsf@gnu.org> <79b4e022-5d46-ae76-2192-9e8594c43d8d@gmail.com> <83o8eevwym.fsf@gnu.org> <8ed0330c-482f-3f82-8b37-308328a314b5@gmail.com> <83v98fpmc0.fsf@gnu.org> <37977025-eb33-5456-651d-61fc202a6d9a@gmail.com> <837dkupfat.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="blaine.gmane.org:116.202.254.214"; logging-data="26041"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 Cc: emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Apr 29 21:18:54 2021 Return-path: Envelope-to: ged-emacs-devel@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 1lcCBa-0006dj-C9 for ged-emacs-devel@m.gmane-mx.org; Thu, 29 Apr 2021 21:18:54 +0200 Original-Received: from localhost ([::1]:58552 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lcCBZ-0006ip-Fz for ged-emacs-devel@m.gmane-mx.org; Thu, 29 Apr 2021 15:18:53 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:34166) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lcCA2-0006HJ-UQ for emacs-devel@gnu.org; Thu, 29 Apr 2021 15:17:19 -0400 Original-Received: from mail-lj1-x22e.google.com ([2a00:1450:4864:20::22e]:45830) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lcCA0-0001Or-EV; Thu, 29 Apr 2021 15:17:18 -0400 Original-Received: by mail-lj1-x22e.google.com with SMTP id d15so26553330ljo.12; Thu, 29 Apr 2021 12:17:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:subject:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=URxl2V1z6P2LnmCxFPgubmadis7bQ5AjmqV4RzvaU+8=; b=a+/bQqyRhxNWYgEwYuK9EWjvq18GIle2NuPDOV0GX7KbF3AAgnpwxRIzRi87DVVRTs VuQdB2OuT3yAELEo78Zmko+1Ri7jkNSJUaxHY/+G16l7rbGyViPFrKWqxXv8iKd3Lh6t xS+BG7OIZ9FEubj2udQyIRJBNKiYa3gkNw2mNNaImOK2Ta/+S5+d5tIgYgwHVQQhXhRq qokmu7vXiZ2lnE7R8XtW4A4kuWEcjeKoa5LGJ9ydozYLBXRqFUF3zKps/G0kRy/KhkeZ ELfe+hAUCVxDG7RhGvnAjq40dVR4KXHz+bmJjg2xKwYwO+YAJ7PLZ7+XJpO9qz/7Bxu+ Y5CQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=URxl2V1z6P2LnmCxFPgubmadis7bQ5AjmqV4RzvaU+8=; b=WXKuwIz+u8vy/xTPZF4nCA2OgtIyg/NsjIO2jXBCUr0yUShNRt/GvoFlHSaLpeEMWr q1A3ddwLGs9fp3X0PWnDEj3QJv8HO8KYbzOUUViQAZtDvlQlQSBnpvWrOecEib0R7UTi kSvkQMEYrKBw+NOVVMRAME8p3I0VXpWGI+NrqRJnB2xKgbuOiYEK5SU3648G/9fsbmCH Fsa1eoROM6kQvabvW/HoZzbJaqUxAuSvKyowvmk8qzp2L1crB0MePyQFvgmrvbb4Rm2S ViTyoyjO5Wq91XsQ3AvFAbV1jK1BMBwX1I4wWqenYhJfNitw7+mKZmDrUWGyiOa11Dw3 p4OA== X-Gm-Message-State: AOAM532QuwjM4i2EKm4CchwY1lINV1r7ymnVgC9laIu47h/sx2+uxR71 474/Hy+Rqpy1PoX4T+ZCtvHmpuoAiqM= X-Google-Smtp-Source: ABdhPJwDSwRJf8gYlz8UTKhf+WiSJZ5oha/ctcNJycE9MBDry9rSH8e4EWjIAGVe6/nmp+L8lLt5GA== X-Received: by 2002:a2e:165d:: with SMTP id 29mr872246ljw.359.1619723832817; Thu, 29 Apr 2021 12:17:12 -0700 (PDT) Original-Received: from ?IPv6:2a02:2168:b115:9d00:7a98:444f:a95a:1aef? ([2a02:2168:b115:9d00:7a98:444f:a95a:1aef]) by smtp.gmail.com with ESMTPSA id w12sm62111lfe.203.2021.04.29.12.17.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 29 Apr 2021 12:17:12 -0700 (PDT) X-Google-Original-From: Nikolay Kudryavtsev In-Reply-To: <837dkupfat.fsf@gnu.org> Content-Language: en-US Received-SPF: pass client-ip=2a00:1450:4864:20::22e; envelope-from=nikolay.kudryavtsev@gmail.com; helo=mail-lj1-x22e.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:268634 Archived-At: I now know what's going on there. buffer.c/init_buffer has some unexec-specific code that remaps memory for the special buffers inherited from temacs. We fail at Fprin1_to_string which uses the " prin1" special buffer. cddf85d256 removed FOR_EACH_BUFFER macro and replaced it everywhere with the use of FOR_EACH_LIVE_BUFFER. Because FOR_EACH_LIVE_BUFFER does not iterate over the " prin1" buffer, it does not get its memory remapped and this breaks print functionality and elisp compilation, which depends on it. FOR_EACH_BUFFER worked before due to buffer structure operating as a linked list and since it's kind of an ugly way of doing things, make sense why Stefan removed it. But I'm not if adding those special buffers to Vbuffer_alist(FOR_EACH_LIVE_BUFFER uses it) would not break anything.