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Re: Optimization of conditional access to globals: thread-unsafe?
Erik Trulsson wrote:
It is also worth noting that just declaring a variable 'volatile' does not
help all that much in making it safer to use in a threded environment if you
have multiple CPUs. (There is nothing that says that a multi-CPU system has
to have any kind of automatic cache-coherence.)
The first sentence here could be misleading, there are LOTS of systems
where there is automatic cache-coherence, and of course the use of
'volatile' on such systems does indeed help. If you are working on
a systemn without cache-coherence, you indeed have big problems, but
that's rarely the case, most multi-processor computers in common use
do guarantee cache coherence.