040000 tree e17742bebe45fb700ea7a56728f19a0c6f987725	thread.lock.algorithm
040000 tree 777c691582007a5e7f3e476207a3ba77a65da0c8	thread.lock
040000 tree b693f3f0c4b0abd53448f0b3a347e6737014e9a0	thread.mutex.requirements
040000 tree 8b78506a14bdec18d8a2272a746ad7d2651b3be5	thread.once