/usr/include/boost/numeric/conversion/detail/ is in libboost1.48-dev 1.48.0-3.
This file is owned by root:root, with mode 0o755.
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/usr/include/boost/numeric/conversion/detail/bounds.hpp
/usr/include/boost/numeric/conversion/detail/conversion_traits.hpp
/usr/include/boost/numeric/conversion/detail/converter.hpp
/usr/include/boost/numeric/conversion/detail/int_float_mixture.hpp
/usr/include/boost/numeric/conversion/detail/is_subranged.hpp
/usr/include/boost/numeric/conversion/detail/meta.hpp
/usr/include/boost/numeric/conversion/detail/numeric_cast_traits.hpp
/usr/include/boost/numeric/conversion/detail/old_numeric_cast.hpp
/usr/include/boost/numeric/conversion/detail/preprocessed/
/usr/include/boost/numeric/conversion/detail/preprocessed/numeric_cast_traits.hpp
/usr/include/boost/numeric/conversion/detail/sign_mixture.hpp
/usr/include/boost/numeric/conversion/detail/udt_builtin_mixture.hpp