Ensure sequential consistency in fallback implementation when requested #38
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GCC's libatomic does things differently: it effectively inserts a I am not completely sure which approach is the correct one. |
Use `SeqCst` for both acquiring and releasing the spinlock when the corresponding atomic operation is `SeqCst`. This may not be strictly necessary, but it can't hurt.
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Well, I should probably trust GCC's developers' understanding of atomics more than my own, and in any case, the extra assurance can't hurt, so I've modified the PR to acquire the lock with |
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As discussed in #37, use
Ordering::SeqCstwhen unlocking the spinlock if the corresponding atomic operation had a requested ordering ofSeqCst. Otherwise, the existingReleaseordering should be fine. The lock operation can remain unconditionallyAcquire; it always occurs as part of an “atomic” lock/unlock pair.