From owner-sc22wg5@open-std.org Sat Jan 24 00:40:36 2009 Return-Path: X-Original-To: sc22wg5-dom7 Delivered-To: sc22wg5-dom7@www2.open-std.org Received: by www2.open-std.org (Postfix, from userid 521) id 7A080CA6002; Sat, 24 Jan 2009 00:40:36 +0100 (CET) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org Received: from mail1.cray.com (mail1.cray.com [136.162.0.111]) by www2.open-std.org (Postfix) with ESMTP id 6DA5FCA5FED for ; Sat, 24 Jan 2009 00:40:34 +0100 (CET) Received: from beaver.us.cray.com (beaver.us.cray.com [172.30.74.51]) by mail1.cray.com (8.13.6/8.13.3/gw-5323) with ESMTP id n0NNeNO0006017 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 23 Jan 2009 17:40:23 -0600 (CST) Received: from CFEXFE01.us.cray.com (cfexfe01.us.cray.com [172.30.74.93]) by beaver.us.cray.com (8.13.8/8.13.3/hub-5273) with ESMTP id n0NNeM9l001166; Fri, 23 Jan 2009 17:40:22 -0600 Received: from mh-dhcp-172-31-16-180.us.cray.com ([172.31.16.180]) by CFEXFE01.us.cray.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.3959); Fri, 23 Jan 2009 17:40:22 -0600 Message-ID: <497A5617.3080902@cray.com> Date: Fri, 23 Jan 2009 17:43:19 -0600 From: Bill Long Reply-To: longb@cray.com Organization: Cray Inc. User-Agent: Thunderbird 2.0.0.9 (Macintosh/20071031) MIME-Version: 1.0 To: Van.Snyder@jpl.nasa.gov, MPI-3 Fortran working group Cc: WG5 Subject: Re: [MPI3 Fortran] (j3.2006) (SC22WG5.3917) (SC22WG5.3909) [ukfortran] [MPI3 Fortran] MPI non-blocking transfers References: <49776DF7.1040900@cray.com> <20090121211748.130A5C178D9@www2.open-std.org> <20090121224014.6CB63C178D9@www2.open-std.org> <20090121234200.4F3BDCA3434@www2.open-std.org> <20090122000407.D5A8ECA3434@www2.open-std.org> <1232658808.15119.824.camel@math.jpl.nasa.gov> <20090123095622.CBD80CA5FED@www2.open-std.org> <20090123190515.A5B24CA5FE6@www2.open-std.org> <497A1CE5.3000708@cray.com> <20090123204209.615C8CA5FED@www2.open-std.org> <1232747203.15119.979.camel@math.jpl.nasa.gov> <497A51B9.3080304@cray.com> <1232753543.15119.989.camel@math.jpl.nasa.gov> In-Reply-To: <1232753543.15119.989.camel@math.jpl.nasa.gov> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 23 Jan 2009 23:40:22.0470 (UTC) FILETIME=[F54AAE60:01C97DB3] X-Cray-VirusStatus: clean Sender: owner-sc22wg5@open-std.org Precedence: bulk Van Snyder wrote: > > The copy-in/copy-out problem appears to be pretty simple: Define the > buffer dummy argument of MPI_Isend to be ASYNCHRONOUS and assumed size. > Then if somebody hands it an assumed-shape or pointer buffer that's not > contiguous, the code falls afoul of C1239 or C1240. If the user's data > isn't contiguous, it's his responsibility to do the copying at the right > time. > > > Yes, exactly. That was my solution #1. (The alternative, #2, was to have MPI routines with assumed-shape dummies, which requires a rewrite of the MPI library, at least at the top layer for certain routines.) The real question is whether "keep rewriting your code until the compiler accepts it" is a "solution" to the MPI group. Realistically, I think it is the where we'll end up. I just want to make sure the MPI group fully understands what they are getting. Cheers, Bill -- Bill Long longb@cray.com Fortran Technical Support & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc., 1340 Mendota Heights Rd., Mendota Heights, MN, 55120