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-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,54889de51045a215 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-10-20 18:35:29 PST Path: archiver1.google.com!news2.google.com!news.maxwell.syr.edu!news.he.net!newsfeed1.easynews.com!easynews.com!easynews!elnk-pas-nf1!newsfeed.earthlink.net!stamper.news.pas.earthlink.net!stamper.news.atl.earthlink.net!newsread2.news.atl.earthlink.net.POSTED!not-for-mail Message-ID: <3F948D58.8090605@noplace.com> From: Marin David Condic User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.0.1) Gecko/20020823 Netscape/7.0 (OEM-HPQ-PRS1C03) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: += in ada References: <3F7316F7.219F@mail.ru> <17cd177c.0310010606.52da88f3@posting.google.com> <3F8BC74F.2CFBFF37@0.0> <1066312000.671303@master.nyc.kbcfp.com> <1066322883.139702@master.nyc.kbcfp.com> <3F8F372D.9040801@comcast.net> <3F8F4559.50306@noplace.com> <3F92BB1A.202@comcast.net> <3F937C9E.4070403@comcast.net> <1066654259.402836@master.nyc.kbcfp.com> <3F9420F7.1020105@comcast.net> <1066673017.140846@master.nyc.kbcfp.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 21 Oct 2003 01:35:28 GMT NNTP-Posting-Host: 209.165.23.103 X-Complaints-To: abuse@earthlink.net X-Trace: newsread2.news.atl.earthlink.net 1066700128 209.165.23.103 (Mon, 20 Oct 2003 21:35:28 EDT) mcondic@mindspring.com NNTP-Posting-Date: Mon, 20 Oct 2003 21:35:28 EDT Organization: EarthLink Inc. -- http://www.EarthLink.net Xref: archiver1.google.com comp.lang.ada:1240 Date: 2003-10-21T01:35:28+00:00 List-Id: Sometimes it is neccessary - either you do a hand optimization or you drop the project. (Been there. Done that. Same processor as the Ariane 5, BTW) But the point ought to be that in the overwhelming bulk of applications, this is not necessary. Most of the time, what the compiler does is *better* and one should leave it alone. Once in a great while, you are so bound by time, you *must* turn off all checks, struggle for every optimization, etc. This is just extremely rare and should not be undertaken lightly. Also, it was never clear to me that leaving in the checks would have saved the Ariane 5. After all, the software did exactly what it was designed to do. It detected a fault, presumed it was a hardware failure and shut down the channel. Had the overflow been trapped by an exception handler instead of the hardware interrupt, the decision would have been the same. The FDA was correct for the Ariane 4. Just that in the Ariane 5, it wasn't a "Failure" so the "Detection" and "Accommodation" was the wrong thing. MDC Hyman Rosen wrote: > > Then the Ariane 4 people counted the cycles. > You were claiming that Ada people believe that this sort > of micro-efficiency is in the domain of the compiler, and > I am pointing you at a prominent real-life project where > this was not the case. > -- ====================================================================== Marin David Condic I work for: http://www.belcan.com/ My project is: http://www.jsf.mil/NSFrames.htm Send Replies To: m c o n d i c @ a c m . o r g "All reformers, however strict their social conscience, live in houses just as big as they can pay for." --Logan Pearsall Smith ======================================================================