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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Oberon and Wirthian languages
Date: Tue, 22 Apr 2014 07:41:19 +0100
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Date: 2014-04-22T07:41:19+01:00
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Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> writes:

> Thank you. It was not at all 100% clear from the RM if Ada offered the
> _guarantee_ that if you had, say, 3 components in a record assignment
> for a atomic bitfield record, that the record assignment would be treated
> as one atomic operation instead of 3 atomic operations (one for each
> component).

Are there CPUs that offer bit-field atomicity? Single bits, maybe. And
what about the fact that these are probably to memory-mapped I/O, and
the device registers may only offer byte/word/longword access?