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: 1094ba,9f0bf354542633fd X-Google-Attributes: gid1094ba,public X-Google-Thread: 103376,d901a50a5adfec3c X-Google-Attributes: gid103376,public From: "Ian St. John" Subject: Re: Fortran or Ada? Date: 1998/10/05 Message-ID: <3618dc33.0@news.passport.ca>#1/1 X-Deja-AN: 397927395 References: <3617AA49.340A5899@icon.fi> <6v9s4t$egn$1@ys.ifremer.fr> X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3110.3 X-Trace: 5 Oct 1998 10:48:19 +0400, 199.166.20.202 Organization: Passport.Ca Newsgroups: comp.lang.fortran,comp.lang.ada Date: 1998-10-05T00:00:00+00:00 List-Id: Michel OLAGNON wrote in message <6v9s4t$egn$1@ys.ifremer.fr>... >In article <3617AA49.340A5899@icon.fi>, Niklas Holsti writes: >> >At the time of writing the software, it might not have been wrong. >But later on, the launch procedure was changed for Ariane 4, and >the computation no longer needed. IMHO, not removing unnecessary >computations that may have side effects IS a "software error". > >The designers failed, IMHO, to note that even if hardware might >be more likely to be wrong than software at time T0, over the whole >expected service life of the system, it was software that had the highest >probability to end up wrong. > IMHO, well tested software doesn't fail. Hardware does. At least, in the sense of random errors. Software can have systematic errors, or design limitations. Random errors and unexpected data indicate hardware problems. The problem in the Arianne 5 case, were that there was no proper review of whether the software testing was *valid* for arianne 5. This was a *management* issue, not a technology issue. If the Arianne 4 had reported such values ( causing overflow ) it *would* have been a hardware error. This was taken into the design, and is correct as such. The software was *correct* for the mission it was designed for ( Arianne 4 ). You cannot expect software re-use without evaluation of the interface/inputs. Nor can you design software with the viewpoint that it *might* be used in the first warp drive spaceship. KISS, and stick to reality.