From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7548 invoked by alias); 18 Apr 2003 03:07:22 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 7534 invoked from network); 18 Apr 2003 03:07:22 -0000 Received: from unknown (HELO mx2.redhat.com) (12.150.115.133) by sources.redhat.com with SMTP; 18 Apr 2003 03:07:22 -0000 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.11.6/8.11.6) with ESMTP id h3I2vaZ29507; Thu, 17 Apr 2003 22:57:36 -0400 Received: from potter.sfbay.redhat.com (potter.sfbay.redhat.com [172.16.27.15]) by int-mx2.corp.redhat.com (8.11.6/8.11.6) with ESMTP id h3I37LW27574; Thu, 17 Apr 2003 23:07:21 -0400 Received: from dot.sfbay.redhat.com (dot.sfbay.redhat.com [172.16.24.7]) by potter.sfbay.redhat.com (8.11.6/8.11.6) with ESMTP id h3I37KM30293; Thu, 17 Apr 2003 20:07:20 -0700 Received: (from rth@localhost) by dot.sfbay.redhat.com (8.11.6/8.11.6) id h3I34vQ13431; Thu, 17 Apr 2003 20:04:57 -0700 X-Authentication-Warning: dot.sfbay.redhat.com: rth set sender to rth@redhat.com using -f Date: Fri, 18 Apr 2003 08:59:00 -0000 From: Richard Henderson To: Richard Kenner Cc: gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org Subject: Re: DATA_ALIGNMENT vs. DECL_USER_ALIGNMENT Message-ID: <20030418030457.GA13422@redhat.com> Mail-Followup-To: Richard Henderson , Richard Kenner , gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org References: <10304180120.AA15817@vlsi1.ultra.nyu.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <10304180120.AA15817@vlsi1.ultra.nyu.edu> User-Agent: Mutt/1.4i X-SW-Source: 2003-04/txt/msg00895.txt.bz2 On Thu, Apr 17, 2003 at 09:20:24PM -0400, Richard Kenner wrote: > No, it's being overloaded for two *other* meanings: > > (1) The user really did set the alignment of the object. > (2) The user really did set the alignment of the object's *type*. I see the two as equivalent. > Yes, but there's a fundamental ambiguity here. If the user says he > wants an object aligned at a 4-byte boundary, is it an error to align > it to a page boundary? If aligning to a page boundary has the effect of inserting padding that a 4-byte boundary wouldn't, yes. I.e. the compiler *shouldn't* emit ".p2align 13" in this situation. r~