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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: How would Ariane 5 have behaved if overflow checking were not
 turned off?
Date: Wed, 16 Mar 2011 15:08:28 +0000
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Date: 2011-03-16T15:08:28+00:00
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"robin" <robin51@dodo.com.au> writes:

> Anyone competent in real-time programming would never have let the
> software go with unhandled overflow, because such an event would
> result in failure of the mission.

The engineers, being competent in tightly-constrained real-time
programming, found that installing exception handlers cost cpu cycles
they could not afford, so looked at all the potential overflow sites and
found that _this_ one could only occur if there was a hardware
failure. Even if they had installed an exception handler, the only
proper response would have been to shutdown this node and hand over to
the alternate; and this was the action that would result from not having
an exception handler in the first place. So, after considerable thought,
they decided against having an exception handler.

Sounds like good engineering to me.