Volatile Worthless or Not

Dmitriy Vyukov
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July 9, 2009 6:57 AM PDT
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#1
Quoting - chris
Over at this blog, Arch Robinson claimed that volatile is almost worthless for multithreaded programming.  I, Chris, argue that volatile is necessary in order for memory fences to work with lock free programming.  Can anyone clarify this?

http://software.intel.com/en-us/blogs/2007/11/30/volatile-almost-useless-for-multi-threaded-programming/

Arch is referring to ISO C++'s volatile which has nothing to do with multi-threading, memory fences and lock-free programming.
And you are probably referring to Microsoft Visual C++'s volatile which is basically promoted to the rank of multi-threading synchronization primitive.

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