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From: "robin" <robin51@dodo.com.au>
Subject: Re: How would Ariane 5 have behaved if overflow checking were notturned off?
Date: Wed, 16 Mar 2011 21:41:10 +1100
Date: 2011-03-16T21:41:10+11:00	[thread overview]
Message-ID: <4d80b140$0$43832$c30e37c6@exi-reader.telstra.net> (raw)
In-Reply-To: op.vscizsqqlzeukk@jellix.jlfencey.com

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Vinzent Hoefler <0439279208b62c95f1880bf0f8776eeb@t-domaingrabbing.de> wrote in message ...
>Elias Salomão Helou Neto wrote:

>> Since then I have been wondering. If compiler checking where actually
>> turned on, what would have happened?

>The same, according to the specification.

>> How could it avoid the disaster?

>Not at all.

On the contrary., an error handler would have performed
something useful.
The crux of the matter is that the data bus would not have been
loaded with an error number [which was then treated as guidance data].

>> Right now I think of three possibilities, the two former seem very
>> unlikely to me.
>
>> a) It would, even if the problem went undetected during testing, have
>> made the developers actually develop code handling this exceptional
>> possibility.

>By handling it exactly the way it was supposed to be:

>Assuming a hardware error and leave control to the redundant subsystem.

That was the major blunder that they made,
namely, treating a programming error as a hardware error.
By doing that, they guaranteed failure of the mission.

>> Which one, if any, is close to reality?

>As it has been mentioned here many times before, the software behaved
>exactly as specified and it is very unlikely that _any_ error handling
>could have avoided the problem

An error handler would have rescued the mission.





  reply	other threads:[~2011-03-16 10:41 UTC|newest]

Thread overview: 79+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-14 15:49 How would Ariane 5 have behaved if overflow checking were not turned off? Elias Salomão Helou Neto
2011-03-14 16:17 ` KK6GM
2011-03-14 19:25   ` Yannick Duchêne (Hibou57)
2011-03-14 19:28     ` Vinzent Hoefler
2011-03-14 20:28     ` KK6GM
2011-03-15  4:02       ` Yannick Duchêne (Hibou57)
2011-03-15  4:53         ` Shark8
2011-03-14 18:29 ` Vinzent Hoefler
2011-03-16 10:41   ` robin [this message]
2011-03-16 15:16     ` How would Ariane 5 have behaved if overflow checking were notturned off? Simon Wright
2011-03-17 11:48       ` robin
2011-03-16 16:58     ` Martin Krischik
2011-03-16 23:39       ` How would Ariane 5 have behaved if overflow checking werenotturned off? robin
2011-03-17 18:48         ` Vinzent Hoefler
2011-03-18 12:06         ` Alex R. Mosteo
2011-03-18 21:15           ` How would Ariane 5 have behaved if overflow checking were not turned off? robin
2011-03-20 10:42             ` Vinzent Hoefler
2011-03-20 17:06         ` How would Ariane 5 have behaved if overflow checking werenotturned off? Martin Krischik
2011-03-20 17:11         ` Martin Krischik
2011-03-20 18:10           ` Dmitry A. Kazakov
2011-03-21 13:24         ` Leif Roar Moldskred
2011-03-20 13:07       ` How would Ariane 5 have behaved if overflow checking were notturned off? Florian Weimer
2011-03-20 17:00         ` Martin Krischik
2011-03-20 20:17           ` Florian Weimer
2011-03-20 20:37             ` Vinzent Hoefler
2011-03-20 20:14         ` Vinzent Hoefler
2011-03-16 18:20     ` Vinzent Hoefler
2011-03-16 18:29       ` Hyman Rosen
2011-03-16 18:55         ` Vinzent Hoefler
2011-03-16 19:40         ` KK6GM
2011-03-16 20:52           ` Hyman Rosen
2011-03-16 21:02             ` KK6GM
2011-03-16 21:09             ` Shark8
2011-03-16 21:13               ` Hyman Rosen
2011-03-16 21:35                 ` Shark8
2011-03-16 22:27             ` Vinzent Hoefler
2011-03-16 21:04           ` Shark8
2011-03-16 21:10             ` Hyman Rosen
2011-03-16 21:27               ` KK6GM
2011-03-16 21:31               ` Shark8
2011-03-16 22:32               ` Vinzent Hoefler
2011-03-18 21:14           ` How would Ariane 5 have behaved if overflow checking were not turned off? robin
2011-03-16 23:46       ` How would Ariane 5 have behaved if overflow checking werenotturned off? robin
2011-03-17  0:26         ` Simon Wright
2011-03-17 11:01           ` Georg Bauhaus
2011-03-17 11:04           ` robin
2011-03-17 13:36             ` Niklas Holsti
2011-03-18 21:13               ` How would Ariane 5 have behaved if overflow checking were not turned off? robin
2011-03-19 10:12                 ` Niklas Holsti
2011-03-17 22:51         ` How would Ariane 5 have behaved if overflow checking werenotturned off? Vinzent Hoefler
2011-03-18 21:13           ` How would Ariane 5 have behaved if overflow checking were not turned off? robin
2011-03-20 10:42             ` Vinzent Hoefler
2011-03-15  6:28 ` Stephen Leake
2011-03-15 17:32   ` Keith Thompson
2011-03-15 17:40     ` KK6GM
2011-03-15 19:44     ` Robert A Duff
2011-03-15 19:12   ` Florian Weimer
2011-03-15 19:45     ` KK6GM
2011-03-15 19:57     ` Vinzent Hoefler
2011-03-20 13:00       ` Florian Weimer
2011-03-20 20:13         ` Vinzent Hoefler
2011-03-15 19:42   ` John B. Matthews
2011-03-17 11:44   ` robin
2011-03-17 18:37     ` Vinzent Hoefler
2011-03-17 23:04       ` How would Ariane 5 have behaved if overflow checking were notturned off? robin
2011-03-18 15:55         ` Vinzent Hoefler
2011-03-17 21:37     ` How would Ariane 5 have behaved if overflow checking were not turned off? Vinzent Hoefler
2011-03-16 10:33 ` robin
2011-03-16 15:08   ` Simon Wright
2011-03-17 12:39     ` robin
2011-03-17 13:41       ` Georg Bauhaus
2011-03-17 23:34         ` How would Ariane 5 have behaved if overflow checking were notturned off? robin
2011-03-18 12:57           ` Hyman Rosen
2011-03-18 16:49             ` KK6GM
2011-03-18 17:18               ` Dmitry A. Kazakov
2011-03-19 17:55                 ` Keith Thompson
2011-03-20 18:39                   ` Robert A Duff
2011-03-17 18:43       ` How would Ariane 5 have behaved if overflow checking were not turned off? Vinzent Hoefler
2011-03-17 20:58       ` Simon Wright
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