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, MSGID_RANDY autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,63ceef1cf4561e32 X-Google-Attributes: gid103376,public From: mjsilva@my-deja.com Subject: Re: Customer balks at Ada -- any hope? Date: 2000/07/19 Message-ID: <8l30la$n9t$1@nnrp1.deja.com>#1/1 X-Deja-AN: 648016796 References: <8l01s4$gnr$1@nnrp1.deja.com> <8l2pqo$im7$1@nnrp1.deja.com> X-Http-Proxy: 1.1 x59.deja.com:80 (Squid/1.1.22) for client 209.239.210.201 Organization: Deja.com - Before you buy. X-Article-Creation-Date: Wed Jul 19 01:35:39 2000 GMT X-MyDeja-Info: XMYDJUIDmjsilva Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.0 (compatible; MSIE 4.01; Windows 98; Compaq) Date: 2000-07-19T00:00:00+00:00 List-Id: In article <8l2pqo$im7$1@nnrp1.deja.com>, wv12@my-deja.com wrote: > > > In article <8l01s4$gnr$1@nnrp1.deja.com>, > mjsilva@my-deja.com wrote: > > We're bidding on a custom industrial controller, and I've proposed to > > write the firmware in Ada. The powers-that-be here are satisfied with > > that, but the customer is afraid nobody will be around to maintain it. > > They're happier with C or C++, alas. Anybody have any good answers to > > their concern? > > > > > I realize that implicit in their position is a belief that Ada offers > > no great tangible benefits to the project (even though the machinery > to > > be controlled is big, expensive and remotely-located), > > C has been known to control big, expensive hardware. One such > example is the mutinode Deep Blue capable of searching a few million > nodes per second. Nowhere did I say otherwise (only a fool would suggest such a thing). However, I firmly believe, as do most Ada users, that for a given amount of effort an Ada program will have fewer defects than a C program. To argue otherwise goes against all the evidence. According to NASA, "The choice of 'C' is to be avoided for our domain of interest because the language lacks the features that permit robust, reliable programming." I have the added datapoint of having determined over this last year that about 90% of customer-discovered bugs in one of our current C products would have been caught by Ada before the product got out the door. Is the speed critical in this project? If so, I see > on reason to avoid Ada that checks every shift, rotate, add, multiply > in your software. How much do you actually know about Ada? A great many checks can be optimized out, and others can be turned off at the discretion of the programmer. I have seen a figure of 7% for "typical" Ada overhead (that's less than 2 months on the Moore curve). So as I see it, 7% vs 1/10 the in-field bugs -- it may not be exact, but it sure looks like a "tangible benefit" to me. > > > course strongly disagree with. As I see it, the arguments are (1) Ada > > will offer tangible benefits, both in reliability and in development > > time, and (2) a decent programmer can pick up similar languages fairly > > easily, especially for maintainence. (Perhaps I should show them some > > Ada source...). Ideas? > Maybe you could try to sell the safety critical side of Ada. But > software that does not get tested will crash, kill, dump core, etc... > (Ariane comes to mind) Who said anything about not testing software?! Am I writing in invisible letters that only you can read? It's a known metric that for each additional development phase that a defect persists after its introduction, the cost of finding and fixing the defect rises by as much as an order of magnitude. Bugs caught in testing are much more expensive to fix than bugs caught at compile time. I have personally spent hours or days finding bugs that Ada would have caught in seconds. And I *hate* debugging! BTW, Ariane was not an Ada failure. It would have come apart exactly the same if the software had been written in C. > > You are not convincing me. Besides, the customer is always right. I didn't set out to convince you, and you clearly are determined not to be convinced, so we'll have to call this one a draw. Why are you so actively antagonistic? I have a longtime C background and I happen to be convinced that Ada is a better solution. If you have evidence that this isn't the case then maybe you can try to convince *me*. Mike Sent via Deja.com http://www.deja.com/ Before you buy.