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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,a0224dc3d1e52f3d X-Google-Attributes: gid103376,public From: dewar@gnat.com Subject: Re: Ada-G, was Re: Streams and Concurrency Date: 1999/01/01 Message-ID: <76hqhk$56h$1@nnrp1.dejanews.com>#1/1 X-Deja-AN: 427654552 References: <76c3tv$acs@bgtnsc02.worldnet.att.net> <76cat4$2ldc$1@news.gate.net> <76dn7b$a35@bgtnsc03.worldnet.att.net> <76fe92$46c$1@platane.wanadoo.fr> <76g91o$udt$1@nnrp1.dejanews.com> <368bdf3c.3097724@news.pacbell.net> X-Http-Proxy: 1.0 x10.dejanews.com:80 (Squid/1.1.22) for client 166.72.71.29 Organization: Deja News - The Leader in Internet Discussion X-Article-Creation-Date: Fri Jan 01 06:38:43 1999 GMT Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.04 [en] (OS/2; I) Date: 1999-01-01T00:00:00+00:00 List-Id: In article <368bdf3c.3097724@news.pacbell.net>, tmoran@bix.com (Tom Moran) wrote: > As a person who spends a fair amount of time testing > portability of new code, and working around the bugs and > limitations of 5 different "Ada 95" compilers, I'd > suggest that anyone thinking of locking themselves into a > vendor-specific "special variations of existing > languages" look very carefully before they leap. That of course is good advice. It is worth emphasizing that the particular case here was a matter of a large customer insisting that (a) they absolutely needed this feature (b) all versions of GNAT seemed to work the way they expected. (c) they would not be able to use any version of GNAT that did not work that way. Most certainly, they realized that they were committing themselves to compilers that worked this way, but they took the position that any compiler not working this way was broken and would not be acceptable for use. Tom is in the business of writing portable library code whose value depends on its being able to run with many different Ada compilers, and there of course, portability is paramount. However, many real world projects are in fact pretty much committed to a single compiler, and even those that don't think they are often are. Indeed, consider this case, the user in question might never have even realized they were doing something that was not legitimate if we had not pointed it out. A lot of code depends on erroneous or implementation dependent constructs without realizing it. Actually one of the most significant cases of dependence on particular compilers arises with the use of specialized library packages. Certainly it is a good thing for compilers to provide useful stuff, but it can be a trap if portability turns out to be important. Note that this is particularly the case if the specs of the routines in question are protected by copyright. Robert Dewar Ada Core Technologies -----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own