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_LOCAL_HEX, FROM_STARTS_WITH_NUMS autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,7e8cebf09cf80560 X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news3.google.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: "Vinzent Hoefler" <0439279208b62c95f1880bf0f8776eeb@t-domaingrabbing.de> Newsgroups: comp.lang.ada Subject: Re: How would Ariane 5 have behaved if overflow checking were notturned off? Date: Sun, 20 Mar 2011 21:14:05 +0100 Message-ID: References: <4d80b140$0$43832$c30e37c6@exi-reader.telstra.net> <87tyeyc548.fsf@mid.deneb.enyo.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit X-Trace: individual.net AsUB/uIzLQp/CDA+X86JfwA9j5r6IW7SXEDQ9/YYbc6h79QJ6d Cancel-Lock: sha1:iIQTVGDW2GW32XC6K5J8RCgBobc= User-Agent: Opera Mail/11.01 (Win32) Xref: g2news1.google.com comp.lang.ada:18336 Date: 2011-03-20T21:14:05+01:00 List-Id: Florian Weimer wrote: > not be considered a programming error. But programming is not a > mechanical activity, and programmers are expected to notice such > problems and address them before the code ships. They /did/ notice it. They reasoned it could not happen in Ariane 4. What they didn't was to take into account that the same code was to be reused in Ariane 5 without further reconsideration. This hardly constitutes a programming error. To construct an example, if I'd designed a speedometer for a car and I know that the car can't be faster than 250 km/h, and so I reason, a representable range for a speed delta for this car would definitely fit within +-327.67 km/h, I did a programming error because someone came along, put the same code into a Bugatti Veyron without even retesting, where then the limit was exceeded and the airbag triggered at about 328 km/h due to a wraparound of the value which the code interpreted as sudden decelaration? Vinzent. -- A C program is like a fast dance on a newly waxed dance floor by people carrying razors. -- Waldi Ravens