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Re: Optimization of conditional access to globals: thread-unsafe?
* Robert Dewar:
>> In the following example, is the access to "Shared" considered
>> unsynchronized even though what looks like a proper lock is used
>> around it?
>
> Yes, it is unsynchronized. Why would you think otherwise?
The signaling rules are dynamic, not static. Only the code path that is
actually taken matters. Sam's corrected code only updates Shared if the
operation in other tasks have been signaled (because of the entry_body
rule and the sequence rule).
(I can't reproduce the conditional store with my GCC 4.2 installation,
though.)