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From: Knute Johnson <nospam@knutejohnson.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Volatile happens before question
Date: Wed, 18 Jan 2012 15:00:02 -0800
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On 1/18/2012 1:16 PM, markspace wrote:
> That's what I was thinking. With folks like Brian Goetz and Bartosz
> saying the system can simply invent values, it's hard to analyze the
> resulting code for any kind of deterministic behavior. Esp. because Java
> is a step away from the machine, and I don't know exactly what sort of
> operations are going to be executed.

I know that the JLS says that variables can have values out of thin air 
but Goetz says on page 36 "When a thread reads a variable without 
synchronization, it may see a stale value, but at least it sees a value 
that was actually placed there by some thread rather then some random 
value.  This safety guarantee is called out-of-thin-air safety."

-- 

Knute Johnson