/usr/include/boost/context/detail/ is in libboost1.62-dev 1.62.0+dfsg-5.
This file is owned by root:root, with mode 0o755.
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/usr/include/boost/context/detail/apply.hpp
/usr/include/boost/context/detail/config.hpp
/usr/include/boost/context/detail/disable_overload.hpp
/usr/include/boost/context/detail/exception.hpp
/usr/include/boost/context/detail/exchange.hpp
/usr/include/boost/context/detail/fcontext.hpp
/usr/include/boost/context/detail/fcontext_arm.hpp
/usr/include/boost/context/detail/fcontext_arm_mac.hpp
/usr/include/boost/context/detail/fcontext_arm_win.hpp
/usr/include/boost/context/detail/fcontext_i386.hpp
/usr/include/boost/context/detail/fcontext_i386_win.hpp
/usr/include/boost/context/detail/fcontext_mips.hpp
/usr/include/boost/context/detail/fcontext_ppc.hpp
/usr/include/boost/context/detail/fcontext_sparc.hpp
/usr/include/boost/context/detail/fcontext_x86_64.hpp
/usr/include/boost/context/detail/fcontext_x86_64_win.hpp
/usr/include/boost/context/detail/index_sequence.hpp
/usr/include/boost/context/detail/invoke.hpp
/usr/include/boost/context/detail/tuple.hpp