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=-2.9 required=5.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII X-Google-Thread: 103376,a00006d3c4735d70 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-14 07:14:12 PST Path: archiver1.google.com!news2.google.com!news.maxwell.syr.edu!newsfeed.media.kyoto-u.ac.jp!newsfeed.icl.net!newsfeed.fjserv.net!proxad.net!usenet-fr.net!enst.fr!melchior!cuivre.fr.eu.org!melchior.frmug.org!not-for-mail From: "Alexandre E. Kopilovitch" Newsgroups: comp.lang.ada Subject: Re: Certified C compilers for safety-critical embedded systems Date: Wed, 14 Jan 2004 18:12:28 +0300 (MSK) Organization: Cuivre, Argent, Or Message-ID: References: <0F6Nb.1623$Tt.642@reader1.news.jippii.net> NNTP-Posting-Host: lovelace.ada-france.org Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 8bit X-Trace: melchior.cuivre.fr.eu.org 1074093200 27265 80.67.180.195 (14 Jan 2004 15:13:20 GMT) X-Complaints-To: usenet@melchior.cuivre.fr.eu.org NNTP-Posting-Date: Wed, 14 Jan 2004 15:13:20 +0000 (UTC) To: comp.lang.ada@ada-france.org Return-Path: In-Reply-To: <0F6Nb.1623$Tt.642@reader1.news.jippii.net>; from Aatu Koskensilta at Wed, 14 Jan 2004 10:01:26 +0200 X-Mailer: Mail/@ [v2.44 MSDOS] X-Virus-Scanned: by amavisd-new-20030616-p5 (Debian) at ada-france.org X-BeenThere: comp.lang.ada@ada-france.org X-Mailman-Version: 2.1.3 Precedence: list List-Id: Gateway to the comp.lang.ada Usenet newsgroup List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , X-Original-Content-Transfer-Encoding: 8bit Xref: archiver1.google.com comp.lang.ada:4400 Date: 2004-01-14T18:12:28+03:00 Aatu Koskensilta wrote: > > Why do you call that reference to G�del's proof "curious"? > > Because it seems flat out wrong. That > > [any compiler for a resonable language] either does not accept some > legal programs, accepts some illegal programs, or never halts for some > inputs > > does not in any sense Hm, _any_? How can you know about _any_ sense? There may be a sense of which you just aren't aware (for example, a sense of _real_ general-purpose programming languages and _real_ requirements for _really_used_ compilers for those languages -;). > follow from G�del's proof. It can't formally follow - just because the quoted statement is not formal - it couples the formal part with informal part, and the latter refers to a hard reality. So, the statement isn't a logical conclusion, it is an opinion about relationship between a particular logical construct and a piece of reality. > > Or you imply that theorems of (mathematical) logic can't have a sense and > > therefore shouldn't be mapped to reality at all? -:) > > No, mathematical logic is very relevant to computer science. I didn't mention computer science at all, I asked about a sense relevant to reality and about a mapping to reality. Alexander Kopilovitch aek@vib.usr.pu.ru Saint-Petersburg Russia