In file included from test.cpp:1:
/usr/include/boost/iostreams/device/file_descriptor.hpp:276:12: error: functional-style cast from 'int const' to 'detail::path' is not allowed
    { open(detail::path(path), mode); }
           ^~~~~~~~~~~~~
In file included from test.cpp:2:
/usr/include/boost/iostreams/stream.hpp:128:5: note: in instantiation of function template specialization 'boost::iostreams::file_descriptor_sink::file_descriptor_sink<int>' requested here
    BOOST_IOSTREAMS_FORWARD( stream, open_impl, Device,
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
/usr/include/boost/iostreams/detail/forward.hpp:56:5: note: instantiated from:
    BOOST_PP_REPEAT_FROM_TO( \
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:24:
/usr/include/boost/preprocessor/repetition/repeat_from_to.hpp:34:34: note: instantiated from:
# define BOOST_PP_REPEAT_FROM_TO BOOST_PP_CAT(BOOST_PP_REPEAT_FROM_TO_, BOOST_PP_AUTO_REC(BOOST_PP_REPEAT_P, 4))
                                 ^
In file included from test.cpp:1:
In file included from /usr/include/boost/iostreams/device/file_descriptor.hpp:26:
In file included from /usr/include/boost/iostreams/detail/path.hpp:31:
In file included from /usr/include/boost/type_traits/is_same.hpp:31:
In file included from /usr/include/boost/type_traits/detail/bool_trait_def.hpp:14:
In file included from /usr/include/boost/type_traits/detail/template_arity_spec.hpp:10:
In file included from /usr/include/boost/mpl/int.hpp:20:
In file included from /usr/include/boost/mpl/aux_/integral_wrapper.hpp:22:
/usr/include/boost/preprocessor/cat.hpp:22:32: note: instantiated from:
#    define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
                               ^
note: (skipping 14 contexts in backtrace; use -fmacro-backtrace-limit=0 to see all)
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:22:
In file included from /usr/include/boost/preprocessor/repetition/enum_binary_params.hpp:19:
/usr/include/boost/preprocessor/tuple/elem.hpp:20:53: note: instantiated from:
#    define BOOST_PP_TUPLE_ELEM(size, index, tuple) BOOST_PP_TUPLE_ELEM_I(size, index, tuple)
                                                    ^
<scratch space>:110:1: note: instantiated from:
BOOST_PP_TUPLE_ELEM_3_2
^
In file included from test.cpp:2:
/usr/include/boost/iostreams/stream.hpp:128:5: note: instantiated from:
    BOOST_IOSTREAMS_FORWARD( stream, open_impl, Device,
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
/usr/include/boost/iostreams/detail/forward.hpp:56:5: note: instantiated from:
    BOOST_PP_REPEAT_FROM_TO( \
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:24:
/usr/include/boost/preprocessor/repetition/repeat_from_to.hpp:34:34: note: instantiated from:
# define BOOST_PP_REPEAT_FROM_TO BOOST_PP_CAT(BOOST_PP_REPEAT_FROM_TO_, BOOST_PP_AUTO_REC(BOOST_PP_REPEAT_P, 4))
                                 ^
In file included from test.cpp:1:
In file included from /usr/include/boost/iostreams/device/file_descriptor.hpp:26:
In file included from /usr/include/boost/iostreams/detail/path.hpp:31:
In file included from /usr/include/boost/type_traits/is_same.hpp:31:
In file included from /usr/include/boost/type_traits/detail/bool_trait_def.hpp:14:
In file included from /usr/include/boost/type_traits/detail/template_arity_spec.hpp:10:
In file included from /usr/include/boost/mpl/int.hpp:20:
In file included from /usr/include/boost/mpl/aux_/integral_wrapper.hpp:22:
/usr/include/boost/preprocessor/cat.hpp:22:32: note: instantiated from:
#    define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
                               ^
note: (skipping 14 contexts in backtrace; use -fmacro-backtrace-limit=0 to see all)
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:22:
In file included from /usr/include/boost/preprocessor/repetition/enum_binary_params.hpp:19:
/usr/include/boost/preprocessor/tuple/elem.hpp:20:53: note: instantiated from:
#    define BOOST_PP_TUPLE_ELEM(size, index, tuple) BOOST_PP_TUPLE_ELEM_I(size, index, tuple)
                                                    ^
In file included from test.cpp:2:
/usr/include/boost/iostreams/stream.hpp:128:5: note: instantiated from:
    BOOST_IOSTREAMS_FORWARD( stream, open_impl, Device,
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
/usr/include/boost/iostreams/detail/forward.hpp:56:5: note: instantiated from:
    BOOST_PP_REPEAT_FROM_TO( \
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:24:
/usr/include/boost/preprocessor/repetition/repeat_from_to.hpp:34:34: note: instantiated from:
# define BOOST_PP_REPEAT_FROM_TO BOOST_PP_CAT(BOOST_PP_REPEAT_FROM_TO_, BOOST_PP_AUTO_REC(BOOST_PP_REPEAT_P, 4))
                                 ^
In file included from test.cpp:1:
In file included from /usr/include/boost/iostreams/device/file_descriptor.hpp:26:
In file included from /usr/include/boost/iostreams/detail/path.hpp:31:
In file included from /usr/include/boost/type_traits/is_same.hpp:31:
In file included from /usr/include/boost/type_traits/detail/bool_trait_def.hpp:14:
In file included from /usr/include/boost/type_traits/detail/template_arity_spec.hpp:10:
In file included from /usr/include/boost/mpl/int.hpp:20:
In file included from /usr/include/boost/mpl/aux_/integral_wrapper.hpp:22:
/usr/include/boost/preprocessor/cat.hpp:22:32: note: instantiated from:
#    define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
                               ^
note: (skipping 14 contexts in backtrace; use -fmacro-backtrace-limit=0 to see all)
In file included from test.cpp:2:
/usr/include/boost/iostreams/stream.hpp:128:5: note: instantiated from:
    BOOST_IOSTREAMS_FORWARD( stream, open_impl, Device,
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
/usr/include/boost/iostreams/detail/forward.hpp:56:5: note: instantiated from:
    BOOST_PP_REPEAT_FROM_TO( \
    ^
In file included from test.cpp:2:
In file included from /usr/include/boost/iostreams/stream.hpp:18:
In file included from /usr/include/boost/iostreams/detail/forward.hpp:24:
/usr/include/boost/preprocessor/repetition/repeat_from_to.hpp:34:34: note: instantiated from:
# define BOOST_PP_REPEAT_FROM_TO BOOST_PP_CAT(BOOST_PP_REPEAT_FROM_TO_, BOOST_PP_AUTO_REC(BOOST_PP_REPEAT_P, 4))
                                 ^
In file included from test.cpp:1:
In file included from /usr/include/boost/iostreams/device/file_descriptor.hpp:26:
In file included from /usr/include/boost/iostreams/detail/path.hpp:31:
In file included from /usr/include/boost/type_traits/is_same.hpp:31:
In file included from /usr/include/boost/type_traits/detail/bool_trait_def.hpp:14:
In file included from /usr/include/boost/type_traits/detail/template_arity_spec.hpp:10:
In file included from /usr/include/boost/mpl/int.hpp:20:
In file included from /usr/include/boost/mpl/aux_/integral_wrapper.hpp:22:
/usr/include/boost/preprocessor/cat.hpp:22:32: note: instantiated from:
#    define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
                               ^
note: (skipping 14 contexts in backtrace; use -fmacro-backtrace-limit=0 to see all)
test.cpp:9:23: note: in instantiation of function template specialization 'boost::iostreams::stream<boost::iostreams::file_descriptor_sink, std::char_traits<char>, std::allocator<char> >::stream<int>' requested here
    fdstream(int fd): stream<file_descriptor_sink>(fd) {}
                      ^
1 error generated.