Re: volatile is ignored by my compiler?
Hyman Rosen wrote:
dietmar_kuehl@yahoo.com wrote:
Judging from the subject of your article and the mention of threads
you seem to assume that volatile has anything to do with threading.
In C++ it has not.
Mark Rosewater, in his many columns about designing the trading
card game Magic The Gathering, often writes that one of the worst
things a game designer can do is to confound the expectations of
players as to how something works. Here's a sample column.
<http://www.wizards.com/magic/magazine/article.aspx?x=mtgcom/daily/mr333>
Given that so many people assume that volatile data and multiple
threads work together as a simple form of synchronization, perhaps
they should.
They do on some systems (as an extension).
It would be EXTREMELY expensive on other systems, where volatile is
actually used as originally intended - for accessing memory mapped
devices. Would you like a 128-way Itanium system do invalidate all
on-chip caches, just in case?
Bo Persson
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