From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Emacs port to gcc -fcheck-pointer-bounds Date: Sun, 10 Dec 2017 19:27:13 +0200 Message-ID: <83efo2trwu.fsf@gnu.org> References: <83indhwcx5.fsf@gnu.org> <83k1xwuwq3.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1512926887 29083 195.159.176.226 (10 Dec 2017 17:28:07 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 10 Dec 2017 17:28:07 +0000 (UTC) Cc: pipcet@gmail.com, Emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Dec 10 18:28:03 2017 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eO5OV-0007O6-9w for ged-emacs-devel@m.gmane.org; Sun, 10 Dec 2017 18:28:03 +0100 Original-Received: from localhost ([::1]:45401 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eO5Oc-000754-GY for ged-emacs-devel@m.gmane.org; Sun, 10 Dec 2017 12:28:10 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59932) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eO5Nz-00072i-CL for Emacs-devel@gnu.org; Sun, 10 Dec 2017 12:27:32 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eO5Nw-0000Mv-7z for Emacs-devel@gnu.org; Sun, 10 Dec 2017 12:27:31 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:50608) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eO5Nw-0000Ml-4B; Sun, 10 Dec 2017 12:27:28 -0500 Original-Received: from [176.228.60.248] (port=2326 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1eO5Nv-0007VQ-Hk; Sun, 10 Dec 2017 12:27:27 -0500 In-reply-to: (message from Paul Eggert on Sat, 9 Dec 2017 23:10:43 -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: 2.1.21 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" Xref: news.gmane.org gmane.emacs.devel:220852 Archived-At: > From: Paul Eggert > Cc: pipcet@gmail.com, Emacs-devel@gnu.org > Date: Sat, 9 Dec 2017 23:10:43 -0800 > > 1. The Emacs C code should store pointer values only in objects declared to be > of type pointer. Otherwise, every time Emacs converted an integer to a pointer, > machine code generated by -fcheck-pointer-bounds would disable bounds checking > for that pointer (which would defeat the point of bounds checking). > > This is what the first patch does. I like this patch anyway, since it cleans up > the Emacs internals a bit and it doesn't significantly affect performance in the > typical case where -fcheck-pointer-bounds is not used. But if we install this patch regardless of -fcheck-pointer-bounds, then the --with-wide-int build will cease working, won't it? Thanks for the other explanations.