From owner-sc22wg5@open-std.org Thu Feb 7 20:20:25 2008 Return-Path: X-Original-To: sc22wg5-dom6 Delivered-To: sc22wg5-dom6@open-std.org Received: by open-std.org (Postfix, from userid 521) id BAEC4D7A81; Thu, 7 Feb 2008 20:20:25 +0100 (CET) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org Received: from laptop.moene.indiv.nluug.nl (a82-93-67-168.adsl.xs4all.nl [82.93.67.168]) by open-std.org (Postfix) with ESMTP id E1B89393D9 for ; Thu, 7 Feb 2008 20:20:10 +0100 (CET) Received: from [127.0.0.1] (ident=toon) by laptop.moene.indiv.nluug.nl with esmtp (Exim 4.68) (envelope-from ) id 1JNCI1-0001y4-KB for sc22wg5@open-std.org; Thu, 07 Feb 2008 20:20:05 +0100 Message-ID: <47AB59E5.5000201@moene.indiv.nluug.nl> Date: Thu, 07 Feb 2008 20:20:05 +0100 From: Toon Moene Organization: Moene Computational Physics, Maartensdijk, The Netherlands User-Agent: Mozilla-Thunderbird 2.0.0.9 (X11/20080109) MIME-Version: 1.0 To: WG5 Subject: Not the Dutch National Activity Report. Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-sc22wg5@open-std.org Precedence: bulk Unfortunately, I haven't yet heard from Matthijs (he has all the contacts with the Dutch Fortran Committee). In the mean time I'll report some activity of my own. I see that we will (again - rolls eyes) have to vote on co-arrays. Well, I will dutifully cast my vote, but this time I decided to actually *do* something about co-arrays, instead of just voting on them. I submitted the following proposal for a paper at the GCC Summit in June this year in Ottawa (http://www.gccsummit.org): -------- 8< -------- 8< --------- 8< ------- 8< --------- Towards an implementation of Co-Array Fortran. There is a good chance that Co-Array Fortran (of which one can find a description here: ftp://ftp.nag.co.uk/sc22wg5/N1651-N1700/N1677.pdf) will be included in the Fortran 2008 Standard. From the article cited above: "A Fortran program containing co-arrays is interpreted as if it were replicated a fixed number of times and all copies were executed asynchronously. Each copy has its own set of data objects and is called an image. The array syntax of Fortran is extended with additional trailing subscripts in square brackets to give a clear and straightforward representation of access to data on other images." I will describe the steps that have to be undertaken to make GNU Fortran capable of compiling Fortran programs using co-arrays. This includes enhancements to the parser, the intermediate description of programs in the Fortran Front End and the necessary support of the run-time library. The request for a Co-Array Fortran implementation in GNU Fortran is an old one: It is the subject of PR 18918 and dates from the 10th of December 2004, 4 months before the release of GCC 4.0, the first with the current GNU Fortran compiler. Although a full implementation - capable of compiling Fortran codes for distributed memory systems - is challenging, an implementation that caters for run-of-the-mill quad-core shared memory PC's that sell for ~ $ 1000 would immediately be useful. -------- 8< -------- 8< --------- 8< ------- 8< --------- Of course, as yet it's only a proposal - it still has to pass the review committee (1 out of 3 papers makes it). But I can always decide (like I did in 2006) to write the paper anyway, regardless of acceptance by the Summit reviewers. Kind regards, and see you Sunday ! -- Toon Moene - e-mail: toon@moene.indiv.nluug.nl - phone: +31 346 214290 Saturnushof 14, 3738 XG Maartensdijk, The Netherlands At home: http://moene.indiv.nluug.nl/~toon/ Progress of GNU Fortran: http://gcc.gnu.org/ml/gcc/2008-01/msg00009.html