Details
Minor - P4 Description
_txn_rollback_to_stable_lookaside_fixup() and _txn_rollback_to_stable_btree() both include a code fragment like this:
/*
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* Copy the stable timestamp, otherwise we'd need to lock it each time
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* it's accessed. Even though the stable timestamp isn't supposed to be
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* updated while rolling back, accessing it without a lock would
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* violate protocol.
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*/
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rollback_timestamp = txn_global->stable_timestamp;
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However, WT_TXN_GLOBAL.stable_timestamp is not declared volatile, so there's nothing to prevent the compiler from reordering or rewriting the instruction.