040000 tree e17742bebe45fb700ea7a56728f19a0c6f987725	thread.lock.algorithm
040000 tree fd54bb2901add9726180e50913c7b0ca1d6ce1b1	thread.lock
040000 tree b2d79bf33902bce817ec393f772ee927db56af6c	thread.mutex.requirements
040000 tree 3ee862f1092b17e9e1704ef91facb90c8f07f763	thread.once