/usr/include/x86_64-linux-gnu/ is in liburcu-dev 0.10.1-1.
This file is owned by root:root, with mode 0o755.
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/usr/include/x86_64-linux-gnu/urcu/
/usr/include/x86_64-linux-gnu/urcu-bp.h
/usr/include/x86_64-linux-gnu/urcu-call-rcu.h
/usr/include/x86_64-linux-gnu/urcu-defer.h
/usr/include/x86_64-linux-gnu/urcu-flavor.h
/usr/include/x86_64-linux-gnu/urcu-pointer.h
/usr/include/x86_64-linux-gnu/urcu-qsbr.h
/usr/include/x86_64-linux-gnu/urcu.h
/usr/include/x86_64-linux-gnu/urcu/arch/
/usr/include/x86_64-linux-gnu/urcu/arch.h
/usr/include/x86_64-linux-gnu/urcu/arch/generic.h
/usr/include/x86_64-linux-gnu/urcu/cds.h
/usr/include/x86_64-linux-gnu/urcu/compiler.h
/usr/include/x86_64-linux-gnu/urcu/config.h
/usr/include/x86_64-linux-gnu/urcu/debug.h
/usr/include/x86_64-linux-gnu/urcu/futex.h
/usr/include/x86_64-linux-gnu/urcu/hlist.h
/usr/include/x86_64-linux-gnu/urcu/lfstack.h
/usr/include/x86_64-linux-gnu/urcu/list.h
/usr/include/x86_64-linux-gnu/urcu/map/
/usr/include/x86_64-linux-gnu/urcu/map/urcu-bp.h
/usr/include/x86_64-linux-gnu/urcu/map/urcu-qsbr.h
/usr/include/x86_64-linux-gnu/urcu/map/urcu.h
/usr/include/x86_64-linux-gnu/urcu/rcuhlist.h
/usr/include/x86_64-linux-gnu/urcu/rculfhash.h
/usr/include/x86_64-linux-gnu/urcu/rculfqueue.h
/usr/include/x86_64-linux-gnu/urcu/rculfstack.h
/usr/include/x86_64-linux-gnu/urcu/rculist.h
/usr/include/x86_64-linux-gnu/urcu/ref.h
/usr/include/x86_64-linux-gnu/urcu/static/
/usr/include/x86_64-linux-gnu/urcu/static/lfstack.h
/usr/include/x86_64-linux-gnu/urcu/static/rculfqueue.h
/usr/include/x86_64-linux-gnu/urcu/static/rculfstack.h
/usr/include/x86_64-linux-gnu/urcu/static/urcu-bp.h
/usr/include/x86_64-linux-gnu/urcu/static/urcu-pointer.h
/usr/include/x86_64-linux-gnu/urcu/static/urcu-qsbr.h
/usr/include/x86_64-linux-gnu/urcu/static/urcu.h
/usr/include/x86_64-linux-gnu/urcu/static/wfcqueue.h
/usr/include/x86_64-linux-gnu/urcu/static/wfqueue.h
/usr/include/x86_64-linux-gnu/urcu/static/wfstack.h
/usr/include/x86_64-linux-gnu/urcu/syscall-compat.h
/usr/include/x86_64-linux-gnu/urcu/system.h
/usr/include/x86_64-linux-gnu/urcu/tls-compat.h
/usr/include/x86_64-linux-gnu/urcu/uatomic/
/usr/include/x86_64-linux-gnu/urcu/uatomic.h
/usr/include/x86_64-linux-gnu/urcu/uatomic/generic.h
/usr/include/x86_64-linux-gnu/urcu/uatomic_arch.h
/usr/include/x86_64-linux-gnu/urcu/urcu-futex.h
/usr/include/x86_64-linux-gnu/urcu/urcu_ref.h
/usr/include/x86_64-linux-gnu/urcu/wfcqueue.h
/usr/include/x86_64-linux-gnu/urcu/wfqueue.h
/usr/include/x86_64-linux-gnu/urcu/wfstack.h