From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri,  9 Dec 2005 10:01:18 -0700
From: Ronald G Minnich <rminnich@lanl.gov>
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To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] const
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David Leimbach wrote:

> Volatile is useful for telling compilers not to stick  data in 
> registers, which is helpful for multi-threaded situations with shared 
> memory ... sometimes :)

and, stuff that tickles hardware. Refer to the old crazy stuff bsd did 
in the early 80s to get around those issues and still optimize drivers. 
Now, wonder if that script could even be found at this point.

I think I missed the part of the discussion that explains how to do 
mmap'ed I/O without volatile, and a good idea of how to tweak the 
compiler, such that:

while (x->statux & BUSY)
	;

works. If the answer is "don't optimize that functions, you idiot!" I'm 
actually ok with that.

ron