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From: Simon Wright <simon@pushface.org>
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Subject: Re: Proof of array initialization in SPARK 2014
Date: Thu, 19 May 2016 19:12:47 +0100
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Dmitrij Novikov <drr73@gmx.de> writes:

>> It may seem that I worry more about speed than correctness, but in
>> hard real time (like radar) when you are bit twiddling registers
>> inside interrupts, you want code that eliminates non-stack memory
>> references.
>
> Are CPUs fast enough for hard real time applications or is it
> necessary to use FPGAs or ASICs?

Normally hard real time systems are also fast real time systems, but
they need not be; the differentiation is that a hard real time system
*must* meet all its deadlines, according to Wikipedia[1].

Myself, I would have thought it possible for only some of the deadlines
to be hard, while others could slip (but then, maybe they wouldn't count
as *dead*lines).

[1] https://en.wikipedia.org/wiki/Real-time_computing#Criteria_for_real-time_computing