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,f8544883f4f8ab29 X-Google-Attributes: gid103376,public From: dewar@gnat.com Subject: Re: Compiler implementation of speciallized needs annexes. Date: 1999/02/25 Message-ID: <7b2mpq$194$1@nnrp1.dejanews.com>#1/1 X-Deja-AN: 448180400 References: <36D3A1EF.E7CA2A8C@physics.BLAH.purdue.BLAH.edu> X-Http-Proxy: 1.0 x6.dejanews.com:80 (Squid/1.1.22) for client 205.232.38.14 Organization: Deja News - The Leader in Internet Discussion X-Article-Creation-Date: Thu Feb 25 05:24:18 1999 GMT Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.04 [en] (OS/2; I) Date: 1999-02-25T00:00:00+00:00 List-Id: In article <36D3A1EF.E7CA2A8C@physics.BLAH.purdue.BLAH.edu>, "Robert T. Sagris" > wrote: > I was wondering why only GNAT implements all of the > specialized needs annex's. All of the other vendors I > looked into implement A, B as they are required. C and D > are also generally implemented by everyone. Rational also > implements G. Actually you should check VSR's carefully, a lot of compilers do NOT fully implement annex D (for example, as far as we know, GNAT is the only compiler that fully implements annex D on VxWorks, including a full implementation of FIFO_Within_Priorities dispatching policy.) > Is this do to a lack of customer demand for these > features or is it something else? It is not so much a "lack of customer demand". Rather it is an issue of how much customer demand there is compared to the cost of implementation. Implementing annex E for instance is a very large task, and one that may well not be justified by customer demand. GNAT certainly has a number of customers for annex E, but if the decision had been a purely commercial one, who knows? In fact we decided very early on in the GNAT project that we would implement all the annexes. This decision was made even before ACT existed, and was part of the commitment of the GNAT project to providing a *complete* freely available Ada 95 system. Since our first validation was for all the annexes, we decided that we would go for 100% validations on all targets. That has not always been easy, but it makes for a consistent guarantee of completeness. Of course not every annex is required in every situation, and that is why it is perfectly practical to use compilers that lack annex features that you do not need. This was after all the whole point of defining optional special needs annexes in the first place. For example, the Intermetrics compiler for the Patriot 2 certainly does NOT need the Information Systems annex (Patriot missiles are not in the habit of performing payroll computations as they fly through the air :-) That being said, it would definitely be nice to see some other compilers implement some of the "missing" annexes. For one thing, it would be interesting to see if different compilers implementing Annex E could really communicate :-) Most certainly every vendor is driven by customer demand, so if you see something that is not implemented, then it is definitely likely to mean that> > I was just wondering > > Robbi Sagris > Robert Dewar Ada Core Technologies -----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own