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From: Pascal Obry <pascal@obry.net>
Newsgroups: comp.lang.ada
Subject: Re: Compiler Revisions Should go Out As Well as Going Up.
Date: Wed, 11 Dec 2013 17:04:45 +0100
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Date: 2013-12-11T17:04:45+01:00
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Le 11/12/2013 15:16, Simon Wright a écrit :
> For most people there's good reason to at least try the latest
> version. Of course you need a good set of regression tests to be able to
> do this!
> 
> But in some cases upgrading is a real problem. I'm thinking of systems
> that have gone through extensive and expensive validation exercises,
> including for example avionics flight tests or missile firings; even if
> you trust the compiler team, you'll have an uphill task to persuade the
> person who signs off (Design Authority, Chief Engineer, ...).
> 
> GNAT 5.02a1 had an off-the-cuff remark a long way down a release note
> that for a certain architecture (the one we were using!) there was a
> one-in-millions chance that a function result would be corrupted,
> because the epilogue code wasn't interrupt-safe; you could use a switch
> (-fno-something-or-other that I don't remember) to prevent
> this. Needless to say we abandoned the upgrade.
> 

Sure but that's quite different as the OP saying that there is nothing
to gain to upgrade except troubles. And I was reacting to that.

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