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Date: Fri, 17 Nov 2017 07:45:49 -0800 (PST)
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Subject: Re: Tests in a software release
From: Shark8 <onewingedshark@gmail.com>
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Xref: feeder.eternal-september.org comp.lang.ada:48963
Date: 2017-11-17T07:45:49-08:00
List-Id: <comp.lang.ada>

On Thursday, November 16, 2017 at 2:44:12 PM UTC-7, G.B. wrote:
> 
> On the contrary: you write the contract's clauses of
> all parties to your compiler and then, once you
> know your code meets the requirements of the contracts,
> you drop checking code accordingly ("optimize") and in
> good conscience.
> 
>     if X /= X or else X /= X then
> 
>        --  what, at compile time,
>        --  for which which kind of X?

IEEE754's NaN would yield true in that case, so you can't simply optimize that away, you'd have to do some analysis of the "="/"/=" operator.