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-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,a00006d3c4735d70 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-16 19:58:25 PST Path: archiver1.google.com!news1.google.com!news2.google.com!news.maxwell.syr.edu!news-out1.nntp.be!propagator2-sterling!news-in-sterling.newsfeed.com!pd7cy2so!pd7cy1no!shaw.ca!border1.nntp.ash.giganews.com!border2.nntp.sjc.giganews.com!border1.nntp.sjc.giganews.com!nntp.giganews.com!local1.nntp.sjc.giganews.com!nntp.comcast.com!news.comcast.com.POSTED!not-for-mail NNTP-Posting-Date: Fri, 16 Jan 2004 21:58:22 -0600 Date: Fri, 16 Jan 2004 22:58:21 -0500 From: "Robert I. Eachus" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Certified C compilers for safety-critical embedded systems References: <0F6Nb.1623$Tt.642@reader1.news.jippii.net> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Message-ID: NNTP-Posting-Host: 24.34.214.193 X-Trace: sv3-0l65uWuTTnVonj8ynnvbLdcO501oMUR41ZrKOm/OQTmPKucak/JGzqgkxBZUNPK4pU0jQEO/aWHkbD1!cURFxtCNy3+Yf+RAswmSY+md5hkQf8HxHLGhTZiVCNcH+elF9u7wmLOO70vNnA== X-Complaints-To: abuse@comcast.net X-DMCA-Complaints-To: dmca@comcast.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Xref: archiver1.google.com comp.lang.ada:4479 Date: 2004-01-16T22:58:21-05:00 List-Id: Georg Bauhaus wrote: > And after reading yours and Robert Eachus' explanations, I trust > there is no way to mechanically decide whether a "real world" compiler > works correctly as described in a consistent standard, even for > the finite amount of input programs that capacity limits > will allow. Is this halfway correct? About that. Even if an Ada compiler completely conforms to the standard it will reject some legal Ada programs. That is what the section of RM 1.1.3 I quoted was talking about. There is no real way to determine for some programs if, absent the capacity limitations, the program would be accepted--other than to try and compile it using a compiler with more capacity. If it succeeds, then you can say that you ran into capacity limitations earlier. (Absent compiler bugs of course.) But if the second and subsequent trials fail, you still haven't found out from the tools whether or not you have a valid Ada program. Having said that, there are tests in the ACATS suite, that AFAIK, have never been successfully compiled by any compiler. But they are still believed to be legal Ada programs. (Mostly floating point programs that require types with digits from 15 to 30. Again, AFIAK some of these correctly compile on VAXes and on IBM mainframes, but no one has yet supported digits 30.) -- Robert I. Eachus "The war on terror is a different kind of war, waged capture by capture, cell by cell, and victory by victory. Our security is assured by our perseverance and by our sure belief in the success of liberty." -- George W. Bush