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,fee8802cc3d8334d X-Google-Attributes: gid103376,public From: mgk25@cl.cam.ac.uk (Markus Kuhn) Subject: Re: Ada and Java. different behaviour. casting long to int problem. Date: 1999/06/17 Message-ID: <7kbbvv$hej$3@pegasus.csx.cam.ac.uk>#1/1 X-Deja-AN: 490743790 References: <7jt2c0$vrb@drn.newsguy.com> <7k57vb$1ipf@drn.newsguy.com> <3766650F.705125B7@pwfl.com> <7k64t7$igo$1@its.hooked.net> <7k689a$ci2@drn.newsguy.com> <3766C842.E1EAB60A@pwfl.com> <3766D1CC.D712895E@itools.symantec.com> <7k8nn5$qcb$1@its.hooked.net> <3767E8A2.EF1A0570@itools.symantec.com> <7k8tv3$3gm@drn.newsguy.com> Organization: U of Cambridge Computer Lab, UK Newsgroups: comp.lang.ada Date: 1999-06-17T00:00:00+00:00 List-Id: Hyman Rosen writes: |> Looks like it's time to mention again that an unhandled exception |> raised by conversion overflow caused the Ariane 5 rocket to go off |> course, resulting in its destruction. |> |> Exceptions don't make a language safe - they just make it more |> likely that bugs will be caught in testing. That's not bad, but |> it's also not a panacea. The problem in the Ariane 5 maiden flight failure was certainly that the relevant subsystem has never been fully tested with the parameters of the new rocket, and not that it was programmed in Ada. Actually, the example shows well, that if it HAD it been tested, the exception that has occured would have pointed immediately to the right location of the problem, instead of just to "something is going wrong here". It is not Ada's fault, that the first full test of the gyro system happened only during the maiden flight. Anyway, the report is certianly worth reading: http://www.esrin.esa.it/htdocs/tidc/Press/Press96/ariane5rep.html Markus -- Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK Email: mkuhn at acm.org, WWW: