/usr/include/boost/context/ is in libboost1.62-dev 1.62.0+dfsg-5.
This file is owned by root:root, with mode 0o755.
..
/usr/include/boost/context/all.hpp
/usr/include/boost/context/detail/
/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
/usr/include/boost/context/execution_context.hpp
/usr/include/boost/context/execution_context_v1.hpp
/usr/include/boost/context/execution_context_v2.hpp
/usr/include/boost/context/execution_context_v2_void.ipp
/usr/include/boost/context/fixedsize_stack.hpp
/usr/include/boost/context/flags.hpp
/usr/include/boost/context/pooled_fixedsize_stack.hpp
/usr/include/boost/context/posix/
/usr/include/boost/context/posix/protected_fixedsize_stack.hpp
/usr/include/boost/context/posix/segmented_stack.hpp
/usr/include/boost/context/preallocated.hpp
/usr/include/boost/context/protected_fixedsize_stack.hpp
/usr/include/boost/context/segmented_stack.hpp
/usr/include/boost/context/stack_context.hpp
/usr/include/boost/context/stack_traits.hpp
/usr/include/boost/context/windows/
/usr/include/boost/context/windows/protected_fixedsize_stack.hpp