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 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,c4cb2c432feebd9d X-Google-Thread: 1094ba,c4cb2c432feebd9d X-Google-Attributes: gid103376,gid1094ba,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news3.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!newsfeed00.sul.t-online.de!t-online.de!newsfeed.freenet.de!news-in.ntli.net!newsrout1-win.ntli.net!ntli.net!news.highwinds-media.com!newspeer1-win.ntli.net!newsfe5-win.ntli.net.POSTED!53ab2750!not-for-mail From: "Dr. Adrian Wrigley" Subject: Re: Ada vs Fortran for scientific applications User-Agent: Pan/0.14.2 (This is not a psychotic episode. It's a cleansing moment of clarity.) Message-ID: Newsgroups: comp.lang.ada,comp.lang.fortran References: <0ugu4e.4i7.ln@hunter.axlog.fr> <%P_cg.155733$eR6.26337@bgtnsc04-news.ops.worldnet.att.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Date: Wed, 24 May 2006 15:43:22 GMT NNTP-Posting-Host: 82.10.238.153 X-Trace: newsfe5-win.ntli.net 1148485402 82.10.238.153 (Wed, 24 May 2006 16:43:22 BST) NNTP-Posting-Date: Wed, 24 May 2006 16:43:22 BST Organization: NTL Xref: g2news2.google.com comp.lang.ada:4415 comp.lang.fortran:10201 Date: 2006-05-24T15:43:22+00:00 List-Id: On Wed, 24 May 2006 15:19:23 +0000, Dick Hendrickson wrote: > > > robin wrote: >> "Dick Hendrickson" wrote in message >> news:PkHcg.90575$Fs1.7198@bgtnsc05-news.ops.worldnet.att.net... >> >>>Ada's is surely better. Knowing that a subscript has to be >>>in range, because it's checked when a value is assigned to >>>the subscript variable, has to be more efficient than what >>>Fortran can do. In general, Fortran has to check the value >>>of the subscripts on every array reference. >> >> >> It can do this only if it is a compiler option. >> It is not a feature the language. > > There's a ambiguous "it" in those sentences. ;) > > But, if "it" refers to Fortran, subscript bounds rules > ARE a feature of the language. You are NEVER allowed to > execute an out-of-bounds array reference in a Fortran > program. ... So what does the standard say must happen if you attempt such an access? Can a program fail unpredictably under such (rather common!) circumstances - as routinely happens in C and C++, sometimes at great cost? -- Adrian