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From: jbg@sei.cmu.edu (John Goodenough)
Newsgroups: comp.lang.ada
Subject: Re: Types defining h/w r/o or w/o registers
Message-ID: <26529@as0c.sei.cmu.edu>
Date: 5 Jun 91 13:59:54 GMT
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In-reply-to: als@bohra.cpg.oz.au's message of 4 Jun 91 14:48:21 GMT
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In article Re: Types defining h/w r/o or w/o registers of 4 Jun 91 14:48:21 GMT als@bohra.cpg.oz.au (Anthony Shipman) writes:

>Wasn't there something in the tasking part of the language for this?  Ada's
>multi-tasking model is shared memory between tasks.  I vaguely recall there was
>a pragma, or something in the machine-dependant chapter, to declare certain
>memory locations as volatile.  Certainly what you have is logically equivalent
>to multi-tasking except that one of the tasks is implemented in hardware.

You are talking here about pragma SHARED, which is not suitable for use with
volatile data.  The Ada 9X study report on shared variables (available from
the usual sources) discusses why pragma SHARED doesn't fit the bill.

John B. Goodenough					Goodenough@sei.cmu.edu
Software Engineering Institute				412-268-6391