From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4926 invoked by alias); 5 Oct 2002 19:45:08 -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 4917 invoked from network); 5 Oct 2002 19:45:07 -0000 Received: from unknown (HELO book.moene.indiv.nluug.nl) (195.109.255.217) by sources.redhat.com with SMTP; 5 Oct 2002 19:45:07 -0000 Received: from local ([127.0.0.1] helo=moene.indiv.nluug.nl) by book.moene.indiv.nluug.nl with esmtp (Exim 3.35 #1 (Debian)) id 17xusl-00009g-00; Sat, 05 Oct 2002 21:46:35 +0200 Message-ID: <3D9F4187.60200@moene.indiv.nluug.nl> Date: Sat, 05 Oct 2002 13:33:00 -0000 From: Toon Moene Organization: Moene Computational Physics, Maartensdijk, The Netherlands User-Agent: Mozilla/5.0 (X11; U; Linux ppc; en-US; rv:1.0.0) Gecko/20020622 Debian/1.0.0-0.woody.1 MIME-Version: 1.0 To: Robert Dewar CC: nathan@codesourcery.com, gcc@gcc.gnu.org Subject: Re: Type based aliasing References: <20021005190011.E5002F2CB7@nile.gnat.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2002-10/txt/msg00363.txt.bz2 Robert Dewar wrote: > < overlap at all, so in this case, g77 would just assume (without > checking) that *ip and *fp wouldn't overlap. > Is that really true? I thought the rule was that if there is any aliasing > then assignment by any alias path is forbidden (this certainly was the > original rule in Fortran, it might have changed, but that would surprise me). The rule is that you can't `define' a dummy argument that's argument-associated with another dummy argument. `Define' in Fortran-speak is to `have a value assigned to it and all of the entities that are associated with it'. Assignment is one way to cause problems here, but not the only one. -- Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290 Saturnushof 14, 3738 XG Maartensdijk, The Netherlands Maintainer, GNU Fortran 77: http://gcc.gnu.org/onlinedocs/g77_news.html Join GNU Fortran 95: http://g95.sourceforge.net/ (under construction)