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: [RFC, PATCH] shrink struct vectorlike_header #2 Date: Tue, 06 Nov 2012 23:28:34 +0200 Message-ID: <834nl22zgd.fsf@gnu.org> References: <50766A2C.8070705@yandex.ru> <50994448.6020602@yandex.ru> <509978BF.6090905@cs.ucla.edu> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1352237326 1345 80.91.229.3 (6 Nov 2012 21:28:46 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 6 Nov 2012 21:28:46 +0000 (UTC) Cc: dmantipov@yandex.ru, monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Nov 06 22:28:55 2012 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 1TVqhb-0007uj-6o for ged-emacs-devel@m.gmane.org; Tue, 06 Nov 2012 22:28:55 +0100 Original-Received: from localhost ([::1]:39002 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TVqhS-0005pe-0d for ged-emacs-devel@m.gmane.org; Tue, 06 Nov 2012 16:28:46 -0500 Original-Received: from eggs.gnu.org ([208.118.235.92]:54695) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TVqhP-0005pV-Ay for emacs-devel@gnu.org; Tue, 06 Nov 2012 16:28:44 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TVqhK-0003GZ-Bj for emacs-devel@gnu.org; Tue, 06 Nov 2012 16:28:43 -0500 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:39837) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TVqhK-0003GR-3Q for emacs-devel@gnu.org; Tue, 06 Nov 2012 16:28:38 -0500 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0MD300H004GJXC00@a-mtaout21.012.net.il> for emacs-devel@gnu.org; Tue, 06 Nov 2012 23:28:36 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0MD300HKE4ZOSN50@a-mtaout21.012.net.il>; Tue, 06 Nov 2012 23:28:36 +0200 (IST) In-reply-to: <509978BF.6090905@cs.ucla.edu> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 X-Received-From: 80.179.55.169 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:154708 Archived-At: > Date: Tue, 06 Nov 2012 12:53:19 -0800 > From: Paul Eggert > Cc: Stefan Monnier , > Emacs development discussions > > > +/* Size of the struct buffer part beyond leading > > + Lisp_Objects, in word_size units. */ > > + > > +#define BUFFER_REST_SIZE \ > > + ((sizeof (struct buffer) - header_size) / word_size - BUFFER_LISP_SIZE) > > This assumes (sizeof (struct buffer) - header_size) is a > multiple of word_size, but that's not necessarily the case. Shouldn't this use offsetof for safer results?