From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3287 invoked by alias); 9 Apr 2003 23:59:22 -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 3268 invoked from network); 9 Apr 2003 23:59:22 -0000 Received: from unknown (HELO frothingslosh.sfbay.redhat.com) (12.150.115.200) by sources.redhat.com with SMTP; 9 Apr 2003 23:59:22 -0000 Received: from frothingslosh.sfbay.redhat.com (localhost.localdomain [127.0.0.1]) by frothingslosh.sfbay.redhat.com (8.12.8/8.12.8) with ESMTP id h39Nwsh2027321; Wed, 9 Apr 2003 16:58:54 -0700 Received: (from rth@localhost) by frothingslosh.sfbay.redhat.com (8.12.8/8.12.8/Submit) id h39NwrZ0027319; Wed, 9 Apr 2003 16:58:54 -0700 X-Authentication-Warning: frothingslosh.sfbay.redhat.com: rth set sender to rth@redhat.com using -f Date: Thu, 10 Apr 2003 02:27:00 -0000 From: Richard Henderson To: Ulrich Weigand Cc: gcc@gcc.gnu.org Subject: Re: DATA_ALIGNMENT vs. DECL_USER_ALIGNMENT Message-ID: <20030409235853.GC23063@redhat.com> Mail-Followup-To: Richard Henderson , Ulrich Weigand , gcc@gcc.gnu.org References: <200304092240.AAA21282@faui11.informatik.uni-erlangen.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200304092240.AAA21282@faui11.informatik.uni-erlangen.de> User-Agent: Mutt/1.4i X-SW-Source: 2003-04/txt/msg00407.txt.bz2 On Thu, Apr 10, 2003 at 12:40:21AM +0200, Ulrich Weigand wrote: > However, the problem remains that on s390, the alignment is not > in fact 'optional' but a hard requirement. (Looking at the > various implementations of DATA_ALIGNMENT, it seems that mmix > also needs this to be handled as required, while for the others > it is indeed optional.) I think I'd prefer that we somehow generate an error for alignments that cannot be supported (for some definition of cannot; I have trouble understanding why labels can't be byte aligned on a byte-addressable machine). As is clear from the Irix problem you quote, the user might have some real need for a particular alignment, and forcing something on them may break things. At least this way we'll fail to compile instead of DTWT. r~