Fix statebuffer race #669
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Fix statebuffer race #669
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The test failing in #668 is actually due to a flakey race condition that has failed in previous runs of CI - on master — on Windows, in CI run 20594583659 from December 30.
I think, in unordered mode, write_idx_.fetch_add(1) assigns a circular buffer position, but the actual data write happens after the position is claimed. Another thread can finish its write and increment count_ past the batch boundary, causing collect() to read a position that the first thread hasn't written to yet.
I was able to reproduce on my machine with the following test on the current codebase, but it should pass currently.