From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6868 invoked by alias); 6 Nov 2009 11:29:10 -0000 Received: (qmail 6860 invoked by uid 22791); 6 Nov 2009 11:29:09 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from mel.act-europe.fr (HELO mel.act-europe.fr) (212.99.106.210) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 06 Nov 2009 11:29:05 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id 3C6F8290012; Fri, 6 Nov 2009 12:29:03 +0100 (CET) Received: from mel.act-europe.fr ([127.0.0.1]) by localhost (smtp.eu.adacore.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YzoG9Bfh0W4Q; Fri, 6 Nov 2009 12:28:57 +0100 (CET) Received: from [192.168.1.2] (83-153-87-54.rev.libertysurf.net [83.153.87.54]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mel.act-europe.fr (Postfix) with ESMTP id 26AAB290001; Fri, 6 Nov 2009 12:28:55 +0100 (CET) From: Eric Botcazou To: Richard Guenther Subject: Re: Do BLKmode bit-fields still exist? Date: Fri, 06 Nov 2009 11:29:00 -0000 User-Agent: KMail/1.9.6 (enterprise 20070904.708012) Cc: Michael Matz , gcc@gcc.gnu.org References: <200911061046.50176.ebotcazou@adacore.com> <84fc9c000911060153m4fbd86efqaa823c71d15543b6@mail.gmail.com> In-Reply-To: <84fc9c000911060153m4fbd86efqaa823c71d15543b6@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200911061228.38766.ebotcazou@adacore.com> Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2009-11/txt/msg00122.txt.bz2 > Isn't it enough to specify DECL_PACKED here? The tree.h docs > about DECL_BIT_FIELD are a bit unspecific compared to > DECL_PACKED. > > /* Nonzero in a FIELD_DECL means it is a bit field, and must be > accessed specially. */ > > vs. > > /* In a FIELD_DECL, indicates this field should be bit-packed. */ > > where it seems, as your field isn't a bitfield, using DECL_PACKED > looks more appropriate? No, DECL_PACKED is an "input" flag for stor-layout.c, it isn't used in the middle-end (except in the recently added contains_packed_reference but this is wrong and should be fixed), the "output" flag that drives the middle-end is DECL_BIT_FIELD. stor-layout.c attempts to clear the latter to improve the code, it never changes the former. -- Eric Botcazou