From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,7767a311e01e1cd X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII Path: g2news2.google.com!news3.google.com!news2.volia.net!keepthis.news.telefonica.de!telefonica.de!news.cs.univ-paris8.fr!proxad.net!cleanfeed2-b.proxad.net!nnrp3-1.free.fr!not-for-mail Date: Sun, 22 Oct 2006 21:32:29 +0200 From: Damien Carbonne User-Agent: Thunderbird 1.5.0.7 (X11/20060909) MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: GNAT compiler switches and optimization References: <1161341264.471057.252750@h48g2000cwc.googlegroups.com> <9Qb_g.111857$aJ.65708@attbi_s21> <434o04-7g7.ln1@newserver.thecreems.com> <4539ce34$1_2@news.bluewin.ch> <453A532F.2070709@obry.net> <9kfq04-sgm.ln1@newserver.thecreems.com> <5vgs04-64f.ln1@newserver.thecreems.com> In-Reply-To: <5vgs04-64f.ln1@newserver.thecreems.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Message-ID: <453bc74e$0$19614$426a74cc@news.free.fr> Organization: Guest of ProXad - France NNTP-Posting-Date: 22 Oct 2006 21:32:30 MEST NNTP-Posting-Host: 82.235.135.166 X-Trace: 1161545550 news-1.free.fr 19614 82.235.135.166:49384 X-Complaints-To: abuse@proxad.net Xref: g2news2.google.com comp.lang.ada:7139 Date: 2006-10-22T21:32:30+02:00 List-Id: Jeffrey Creem a �crit : > Followup on the bug report. > > One of the comments asserted that the two programs were not equivilent > though I am not yet 100% convinced that I believe it yet. > > > > Can someone that understands FORTRAN better make an argument about the > "closeness" of this approach v.s. the other? I've been following this thread for some times and I'm not a Fortran Guru,however, IIRC, Fortran arrays and Ada arrays don't have the same memory layout (Something like row major order and column major order). I've not compared programs of this thread with care, but I've the feeling that this could change things. Some years ago, I had to mix Ada and Fortran, and I remember that we had to invert loops order to obtain the same result. One would need to add 'pragma Convention (Fortran, Real_Matrix)' on Ada side to obtain the same result, or to exchange loops. My knowledge of Fortran was limited to Fortran 77, and I don't know if this is still valid with Fortran 95 or later. But if is still true, I would not consider the 2 programs as equivalent. Regards Damien Carbonne