From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23094 invoked by alias); 10 Apr 2003 20:45:30 -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 23074 invoked from network); 10 Apr 2003 20:45:29 -0000 Received: from unknown (HELO nile.gnat.com) (205.232.38.5) by sources.redhat.com with SMTP; 10 Apr 2003 20:45:29 -0000 Received: by nile.gnat.com (Postfix, from userid 338) id 7C8A8F2A67; Thu, 10 Apr 2003 16:45:29 -0400 (EDT) To: geoffk@geoffk.org, weigand@immd1.informatik.uni-erlangen.de Subject: Re: DATA_ALIGNMENT vs. DECL_USER_ALIGNMENT Cc: gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org, kenner@vlsi1.ultra.nyu.edu Message-Id: <20030410204529.7C8A8F2A67@nile.gnat.com> Date: Thu, 10 Apr 2003 20:52:00 -0000 From: dewar@gnat.com (Robert Dewar) X-SW-Source: 2003-04/txt/msg00456.txt.bz2 > I'm not sure whether this is the preferred fix; in particular > I don't understand why those variables need to have forced > alignment in the first place ... The Ada semantics is that they must have the indicated alignment. It is of course always fine to give a larger alignment that is a multiple of the requested alignment (it's just a special case of meeting the alignment requirement). We are discussing now exactly what the relation between the Ada semantics and the gcc semantics for alignment. Right now, it looks like the alignment should be forced for subtypes and not forced for objects, and that is correct provided that objects are always given an alignment at least as large as that of the subtype.