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=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.43.130.198 with SMTP id hn6mr41911849icc.26.1430697243751; Sun, 03 May 2015 16:54:03 -0700 (PDT) X-Received: by 10.50.4.34 with SMTP id h2mr106185igh.7.1430697243738; Sun, 03 May 2015 16:54:03 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!feeder.eternal-september.org!news.glorb.com!l13no13486582iga.0!news-out.google.com!kd3ni7465igb.0!nntp.google.com!l13no13486575iga.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Sun, 3 May 2015 16:54:03 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=123.2.70.40; posting-account=S_MdrwoAAAD7T2pxG2e393dk6y0tc0Le NNTP-Posting-Host: 123.2.70.40 References: <201505021834588468-rblove@airmailnet> <9f20f713-d65c-471d-ab7c-d314a14fdcd0@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <3e8a4ac6-b0cd-445d-8e9c-82ce8f7f9fee@googlegroups.com> Subject: Re: Boeing 787 integer overflow From: robin.vowels@gmail.com Injection-Date: Sun, 03 May 2015 23:54:03 +0000 Content-Type: text/plain; charset=ISO-8859-1 Xref: news.eternal-september.org comp.lang.ada:25710 Date: 2015-05-03T16:54:03-07:00 List-Id: On Monday, May 4, 2015 at 2:03:55 AM UTC+10, Peter Chapin wrote: > On Sun, 3 May 2015, Maciej Sobczak wrote: > > >> Can anyone comment on what language Boeing used for this? > > > > It does not matter. The ability to run continuously for 8 months was > > most likely not in the requirements (planes have to be switched off for > > maintenance more frequently than that anyway), so there was no need to > > implement a solution for this. > > I guess it depends on if there is a *requirement* to reboot the system > periodically (less than 8 months) in the maintenance plan. The matter > should be handled somewhere and it seems like it wasn't. In other words it > was just "luck" that these systems have been getting restarted frequently > enough. > > Planes obviously don't fly for 8 months straight and I'm sure they get > maintained, in general, more regularly than that as well. I don't know > precisely which system this issue is connected with, but it seems possible > to me that, in some cases at least, some systems would be left up and > running while others are being maintained. In other words a daily > maintenance schedule may not imply that the counter in question is getting > reset daily. > > A software fix might be nice, such as increasing the counter to 64 bits to > push the overflow time out to something ridiculous, That isn't the solution. The solution is to have an appropriate error handler. > but just adding an > item to the maintenance checklist might also be sufficient. Things like that get overlooked. Maybe not this year, but in 10 years, when everyone has forgotten about it.