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From: Martin Krischik <krischik@users.sourceforge.net>
Newsgroups: comp.lang.ada
Subject: Re: volatile vs aliased
Date: Thu, 06 Oct 2005 10:05:38 +0200
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Date: 2005-10-06T10:05:38+02:00
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Ludovic Brenta wrote:

> pragma Volatile (Variable) says the compiler must not optimise away
> any reads or writes to that variable, and that it may not add extra
> reads or writes beyond those you explicitly request in your program
> text.  You want to use that for hardware registers, where a "read"
> operation may have a side effect such as changing the device's state.

Interesting! So with  pragma Volatile (X) the following two statements are
not the same:

Y := X * X;
Y := X ** 2;

Good to know!

Martin

-- 
mailto://krischik@users.sourceforge.net
Ada programming at: http://ada.krischik.com