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=1.2 required=5.0 tests=BAYES_00,FROM_WORDY, INVALID_MSGID 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: "Ken Garlington" Subject: Re: Customer balks at Ada -- any hope? Date: 2000/07/19 Message-ID: #1/1 X-Deja-AN: 648395895 References: <8l01s4$gnr$1@nnrp1.deja.com> <3974A1D5.1F9AA2E5@Raytheon.com> <3974EE3D.1F8E016E@silver.jhuapl.edu> <3975C3E6.DF4956F4@silver.jhuapl.edu> X-Priority: 3 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600 X-Complaints-To: abuse@flash.net X-Trace: news.flash.net 964047023 216.215.73.136 (Wed, 19 Jul 2000 17:50:23 CDT) Organization: FlashNet Communications, http://www.flash.net X-MSMail-Priority: Normal NNTP-Posting-Date: Wed, 19 Jul 2000 17:50:23 CDT Newsgroups: comp.lang.ada Date: 2000-07-19T00:00:00+00:00 List-Id: "Scott Ingram`" wrote in message news:3975C3E6.DF4956F4@silver.jhuapl.edu... > But I already have to bear that cost so the difference is? If you choose to use C, you only have to bear the support costs for the C compiler. If you choose to use Ada and C, you have to bear the support costs for the Ada and C compiler. I'm still confused as to why you discuss GNAT with respect to this question. GNAT doesn't convert Ada to C (the original suggestion), so why is it relevant? > > > > Are you sure that, if there's a C compiler that runs on the FWW (Future > > > > Wonderful Workstation) host, there will be an Ada compiler that runs on > > > > the > > > > FWW host? > > > > > > o As far as FWWs go, there is always GNAT. And anywhere Linux > > > goes, so will GNAT. > > > > Unfortunately, GNAT does not fit the premise of the question -- an Ada-to-C > > "translator". > > I don't think Mike's original concern included the availability of an Ada-to-C > translator. He was attempting to persuade a reluctant customer that Ada is > a better fit to a particular problem space than the alternatives. Mike said: "We're bidding on a custom industrial controller, and I've proposed to write the firmware in Ada." To which Samuel T. Harris added: "Of course the availability of Ada-to-C translators mitigates the potential for Ada vendor not supporting, or ending support for, current/future hardware! If there is or will be a C compiler then there is or will be an Ada compiler." This was the basis of my most recent discussions. However, feel free to choose your own path: (a) I will limit myself to the controllers with native Ada support (b) I will target (and maintain) GNAT for any controller selected (c) I will assume that any selected controller has a C compiler, and will use an Ada-to-C translator Each has advantages and disadvantages. However, you can't pick the advantages of all of them simultaneously. > I mentioned > GNAT and (I hope I get the right name) Averstar's Ada to C frontend in this > thread as tools that I would consider to mitigate the risk of delivering an Ada > based product. However, you can't apply the GNAT advantages (e.g. price, wide availability) for Averstar, nor the Averstar advantages (can target C) for GNAT. > And it was your question whether the cost of having to support > both an Ada compiler and a C compiler that led down that path. > Now that I > am almost thinking, I have to point out that there really isn't any > justification for > thinking that I need a C compiler to meet Mike's customer needs. Except now you have some new risks to go address (see prior posts). > > More to the point, however, anyone who assumes that 10 or 20 years from now, > > they'll be using the same OS that they are using today is not supported by > > history. > > Tell that to my vaxen. I can speak volumes about VAXen, being responsible for about a hundred of them. Have you purchased a new one lately? Are you running GNAT on VAX/OpenVMS? Has Compaq sent you an Ada (95) compliant version of DEC Ada yet? As a member of the GNAT team said to me not long ago, "What are you doing with those boat anchors?" Why are you switching from FORTRAN on the VAX to C on Unix? Why not just stay with FORTRAN on the VAX? > I thought that the word "specialized" would be a tip that I was trying to > be careful! Will Ada be available for everything? Of course not! Will C be available for most industrial controllers? I suspect so... > My developers still haven't recovered from the shock of moving from Fortran > on Vaxen to C on Unix. Do we meet schedules? Yes. Do we run into compiler > bugs? Yes. Do we have problems switching just from the Sun debugger to the > Solaris debugger, both for C? Yes. So far nothing but business as usual. So > your > point is? My point is, if it's that hard switching from the Sun to the Solaris debugger, how much harder is it to switch from an Ada environment to a C environment midway through a project (as a fallback if the Ada-to-C compiler doesn't work out)? You seem to be making a very persuasive argument that your environment is quite volatile, which would seem to imply that choices that minimize the chance and impact of change are good choices. > That there are valid arguments to dispell those is not a point > I am willing to concede, even though you make a formidable devil's > advocate. As long as you understand that the original problem is 180 degrees from your position. No one is trying to convince an Ada advocate to switch to C. You're trying to convince a C advocate (the customer) that Ada is a better choice. If you base your argument solely on abstractions, without both (a) quantitative, applicable evidence of the value of Ada and (b) acknowledging that there are risks (which you intend to address), they very likely will assume that you're not qualified to work on their project! Do you tend to win over your management (and customers) often with your approach?