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ambiguous overload for operator>> error when using lexical_cast with qvm::vec
by kique G 28 Sep '16

28 Sep '16

Hi, I am trying to use lexical_cast to convert from strings to qvm vectors, but I keep getting an ambiguous operator>> error. I have overloaded the >> operator for istreams and that seems to be working fine when I use it to read from a istringstream. In a lexical_cast, though, I get the "ambiguous overload for operator>>" error. I have tried declaring my operator>> overload inside the std and boost::qvm namespaces to check if it was something related to ADL, but I keep getting the same error. The thing is the other candidates do not seem to make a lot of sense to me. Could somebody please tell me what I am doing wrong? Thanks in advance, Enrique Garcia This is a minimal example (I am building gcc/boost from the last versions on their repositories): #include <iostream> #include <boost/qvm/vec.hpp> #include <boost/lexical_cast.hpp> std::ostream& operator<<(std::ostream& out, boost::qvm::vec<float, 3> const& v) { out << "(" << v.a[0] << "," << v.a[1] << "," << v.a[2] << ")"; } std::istream& operator>>(std::istream& in, boost::qvm::vec<float, 3>& v) { char c; return in >> c >> v.a[0] >> c >> v.a[1] >> c >> v.a[2] >> c; } int main() { boost::qvm::vec<float, 3> vect { 1.0f, 2.0f, 3.0f }; std::cout << vect << std::endl; // This code works just fine. (4.0,5.0,6.0) is printed std::istringstream istream("(4.0,5.0,6.0"); istream >> vect; std::cout << vect << std::endl; // This code generates an ambiguous overload for operator>> error (see below) vect = boost::lexical_cast<boost::qvm::vec<float, 3>>("(1.0,2.0,3.0)"); std::cout << vect << std::endl; return 0; } This is the error I am getting from gcc: In file included from /usr/local/include/boost/config.hpp:61:0, from /usr/local/include/boost/static_assert.hpp:17, from /usr/local/include/boost/qvm/static_assert.hpp:7, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp: In instantiation of 'const bool boost::detail::has_right_shift_impl::operator_exists<std::basic_istream<char>, boost::qvm::vec<float, 3> >::value': /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:179:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl1<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care, false>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:208:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:216:8: required from 'struct boost::has_right_shift<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:241:21: required from 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:158:70: error: ambiguous overload for 'operator>>' (operand types are 'std::basic_istream<char>' and 'boost::qvm::vec<float, 3>') BOOST_STATIC_CONSTANT(bool, value = (sizeof(s_check(((make<Lhs>() BOOST_TT_TRAIT_OP make<Rhs>()),make<has_operator>())))==sizeof(::boost::type_traits::yes_type))); ^ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:120:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__istream_type& (*)(std::basic_istream<_CharT, _Traits>::__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] operator>>(__istream_type& (*__pf)(__istream_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:124:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__ios_type& (*)(std::basic_istream<_CharT, _Traits>::__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>; std::basic_istream<_CharT, _Traits>::__ios_type = std::basic_ios<char>] operator>>(__ios_type& (*__pf)(__ios_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:131:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] operator>>(ios_base& (*__pf)(ios_base&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:259:7: note: candidate: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__streambuf_type*) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__streambuf_type = std::basic_streambuf<char>] operator>>(__streambuf_type* __sb); ^~~~~~~~ In file included from /usr/local/include/boost/type_traits/has_right_shift.hpp:43:0, from /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:39, from /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:42, from /usr/local/include/boost/lexical_cast.hpp:32, from /home/kique/Documents/Bitflow2x/source/main.cpp:58: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:70:13: note: candidate: boost::detail::has_right_shift_impl::no_operator boost::detail::has_right_shift_impl::operator>>(const boost::detail::has_right_shift_impl::any&, const boost::detail::has_right_shift_impl::any&) no_operator operator BOOST_TT_TRAIT_OP (const any&, const any&); ^~~~~~~~ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:808:5: note: candidate: std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, signed char*) [with _Traits = std::char_traits<char>] operator>>(basic_istream<char, _Traits>& __in, signed char* __s) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:803:5: note: candidate: std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, unsigned char*) [with _Traits = std::char_traits<char>] operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s) ^~~~~~~~ In file included from /usr/local/include/boost/config.hpp:61:0, from /usr/local/include/boost/static_assert.hpp:17, from /usr/local/include/boost/qvm/static_assert.hpp:7, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp: In instantiation of 'const bool boost::detail::has_right_shift_impl::operator_returns_void<std::basic_istream<char>, boost::qvm::vec<float, 3> >::value': /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:179:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl1<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care, false>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:208:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:216:8: required from 'struct boost::has_right_shift<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:241:21: required from 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:95:114: error: ambiguous overload for 'operator>>' (operand types are 'std::basic_istream<char>' and 'boost::qvm::vec<float, 3>') BOOST_STATIC_CONSTANT(bool, value = (sizeof(::boost::type_traits::yes_type)==sizeof(returns_void((make<Lhs>() BOOST_TT_TRAIT_OP make<Rhs>(),returns_void_t()))))); ^ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:120:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__istream_type& (*)(std::basic_istream<_CharT, _Traits>::__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] operator>>(__istream_type& (*__pf)(__istream_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:124:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__ios_type& (*)(std::basic_istream<_CharT, _Traits>::__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>; std::basic_istream<_CharT, _Traits>::__ios_type = std::basic_ios<char>] operator>>(__ios_type& (*__pf)(__ios_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:131:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] operator>>(ios_base& (*__pf)(ios_base&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:259:7: note: candidate: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__streambuf_type*) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__streambuf_type = std::basic_streambuf<char>] operator>>(__streambuf_type* __sb); ^~~~~~~~ In file included from /usr/local/include/boost/type_traits/has_right_shift.hpp:43:0, from /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:39, from /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:42, from /usr/local/include/boost/lexical_cast.hpp:32, from /home/kique/Documents/Bitflow2x/source/main.cpp:58: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:70:13: note: candidate: boost::detail::has_right_shift_impl::no_operator boost::detail::has_right_shift_impl::operator>>(const boost::detail::has_right_shift_impl::any&, const boost::detail::has_right_shift_impl::any&) no_operator operator BOOST_TT_TRAIT_OP (const any&, const any&); ^~~~~~~~ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:808:5: note: candidate: std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, signed char*) [with _Traits = std::char_traits<char>] operator>>(basic_istream<char, _Traits>& __in, signed char* __s) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:803:5: note: candidate: std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, unsigned char*) [with _Traits = std::char_traits<char>] operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s) ^~~~~~~~ In file included from /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:42:0, from /usr/local/include/boost/lexical_cast.hpp:32, from /home/kique/Documents/Bitflow2x/source/main.cpp:58: /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp: In instantiation of 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >': /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:241:21: error: 'value' is not a member of 'boost::has_right_shift<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' >::type type; ^~~~ In file included from /usr/local/include/boost/qvm/static_assert.hpp:7:0, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:243:13: error: 'value' is not a member of 'boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >::result_t {aka boost::has_right_shift<std::basic_istream<char>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>}' BOOST_STATIC_ASSERT_MSG((result_t::value || boost::has_right_shift<std::basic_istream<wchar_t>, T >::value), ^ In file included from /usr/local/include/boost/config.hpp:61:0, from /usr/local/include/boost/static_assert.hpp:17, from /usr/local/include/boost/qvm/static_assert.hpp:7, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp: In instantiation of 'const bool boost::detail::has_right_shift_impl::operator_exists<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3> >::value': /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:179:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl1<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care, false>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:208:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:216:8: required from 'struct boost::has_right_shift<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:243:13: required from 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:158:70: error: ambiguous overload for 'operator>>' (operand types are 'std::basic_istream<wchar_t>' and 'boost::qvm::vec<float, 3>') BOOST_STATIC_CONSTANT(bool, value = (sizeof(s_check(((make<Lhs>() BOOST_TT_TRAIT_OP make<Rhs>()),make<has_operator>())))==sizeof(::boost::type_traits::yes_type))); ^ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:120:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__istream_type& (*)(std::basic_istream<_CharT, _Traits>::__istream_type&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>] operator>>(__istream_type& (*__pf)(__istream_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:124:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__ios_type& (*)(std::basic_istream<_CharT, _Traits>::__ios_type&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>; std::basic_istream<_CharT, _Traits>::__ios_type = std::basic_ios<wchar_t>] operator>>(__ios_type& (*__pf)(__ios_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:131:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>] operator>>(ios_base& (*__pf)(ios_base&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:259:7: note: candidate: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__streambuf_type*) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__streambuf_type = std::basic_streambuf<wchar_t>] operator>>(__streambuf_type* __sb); ^~~~~~~~ In file included from /usr/local/include/boost/type_traits/has_right_shift.hpp:43:0, from /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:39, from /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:42, from /usr/local/include/boost/lexical_cast.hpp:32, from /home/kique/Documents/Bitflow2x/source/main.cpp:58: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:70:13: note: candidate: boost::detail::has_right_shift_impl::no_operator boost::detail::has_right_shift_impl::operator>>(const boost::detail::has_right_shift_impl::any&, const boost::detail::has_right_shift_impl::any&) no_operator operator BOOST_TT_TRAIT_OP (const any&, const any&); ^~~~~~~~ In file included from /usr/local/include/boost/config.hpp:61:0, from /usr/local/include/boost/static_assert.hpp:17, from /usr/local/include/boost/qvm/static_assert.hpp:7, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp: In instantiation of 'const bool boost::detail::has_right_shift_impl::operator_returns_void<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3> >::value': /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:179:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl1<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care, false>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:208:4: required from 'const bool boost::detail::has_right_shift_impl::trait_impl<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>::value' /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:216:8: required from 'struct boost::has_right_shift<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:243:13: required from 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:95:114: error: ambiguous overload for 'operator>>' (operand types are 'std::basic_istream<wchar_t>' and 'boost::qvm::vec<float, 3>') BOOST_STATIC_CONSTANT(bool, value = (sizeof(::boost::type_traits::yes_type)==sizeof(returns_void((make<Lhs>() BOOST_TT_TRAIT_OP make<Rhs>(),returns_void_t()))))); ^ In file included from /usr/local/include/c++/7.0.0/iostream:40:0, from /home/kique/Documents/Bitflow2x/source/main.cpp:56: /usr/local/include/c++/7.0.0/istream:120:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__istream_type& (*)(std::basic_istream<_CharT, _Traits>::__istream_type&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>] operator>>(__istream_type& (*__pf)(__istream_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:124:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__ios_type& (*)(std::basic_istream<_CharT, _Traits>::__ios_type&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>; std::basic_istream<_CharT, _Traits>::__ios_type = std::basic_ios<wchar_t>] operator>>(__ios_type& (*__pf)(__ios_type&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:131:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<wchar_t>] operator>>(ios_base& (*__pf)(ios_base&)) ^~~~~~~~ /usr/local/include/c++/7.0.0/istream:259:7: note: candidate: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__streambuf_type*) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; std::basic_istream<_CharT, _Traits>::__streambuf_type = std::basic_streambuf<wchar_t>] operator>>(__streambuf_type* __sb); ^~~~~~~~ In file included from /usr/local/include/boost/type_traits/has_right_shift.hpp:43:0, from /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:39, from /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:42, from /usr/local/include/boost/lexical_cast.hpp:32, from /home/kique/Documents/Bitflow2x/source/main.cpp:58: /usr/local/include/boost/type_traits/detail/has_binary_operator.hpp:70:13: note: candidate: boost::detail::has_right_shift_impl::no_operator boost::detail::has_right_shift_impl::operator>>(const boost::detail::has_right_shift_impl::any&, const boost::detail::has_right_shift_impl::any&) no_operator operator BOOST_TT_TRAIT_OP (const any&, const any&); ^~~~~~~~ In file included from /usr/local/include/boost/qvm/static_assert.hpp:7:0, from /usr/local/include/boost/qvm/vec.hpp:11, from /home/kique/Documents/Bitflow2x/source/main.cpp:57: /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp: In instantiation of 'struct boost::detail::deduce_target_char_impl<boost::detail::deduce_character_type_later<boost::qvm::vec<float, 3> > >': /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:270:89: required from 'struct boost::detail::deduce_target_char<boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:407:92: required from 'struct boost::detail::lexical_cast_stream_traits<const char*, boost::qvm::vec<float, 3> >' /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:468:15: required from 'struct boost::detail::lexical_converter_impl<boost::qvm::vec<float, 3>, const char*>' /usr/local/include/boost/lexical_cast/try_lexical_convert.hpp:196:44: required from 'bool boost::conversion::detail::try_lexical_convert(const Source&, Target&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /usr/local/include/boost/lexical_cast.hpp:41:60: required from 'Target boost::lexical_cast(const Source&) [with Target = boost::qvm::vec<float, 3>; Source = char [14]]' /home/kique/Documents/Bitflow2x/source/main.cpp:83:72: required from here /usr/local/include/boost/lexical_cast/detail/converter_lexical.hpp:243:13: error: 'value' is not a member of 'boost::has_right_shift<std::basic_istream<wchar_t>, boost::qvm::vec<float, 3>, boost::detail::has_right_shift_impl::dont_care>' BOOST_STATIC_ASSERT_MSG((result_t::value || boost::has_right_shift<std::basic_istream<wchar_t>, T >::value), ^ ninja: build stopped: subcommand failed.

2 1

[release] Boost 1.62.0 Release Candidate 1
by Rene Rivera 28 Sep '16

28 Sep '16

The release candidates for the 1.62.0 release are now available at: https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… The SHA256 checksums are as follows: b91c2cda8bee73ea613130e19e72c9589e9ef0357c4c5cc5f7523de82cce11f7 boost_1_62_0_rc1.7z 36c96b0f6155c98404091d8ceb48319a28279ca0333fba1ad8611eb90afb2ca0 boost_1_62_0_rc1.tar.bz2 440a59f8bc4023dbe6285c9998b0f7fa288468b889746b1ef00e8b36c559dce1 boost_1_62_0_rc1.tar.gz 084b2e0638bbe0975a9e43e21bc9ceae33ef11377aecab3268a57cf41e405d4e boost_1_62_0_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. Thanks, the release managers. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

5 6

[boost][heap] Which heap to use.
by degski 27 Sep '16

27 Sep '16

Hi All, I seem to remember reading about this [the subject of this post] in the docs, but I don't seem to be able to find it [that page] now. What criteria should I use to choose a specific Boost.Heap implementation (skew, fibonacci etc), from the ones provided by the Boost.Heap library? Thanks in advance and have a good day, degski

3 10

newbie !!
by MAURICE Jean 27 Sep '16

27 Sep '16

Hi, This is my second 'account' to this mailing list. In fact I am a freelance who works for a company that works for another company and when I am somewhere I can't have access to the 'elsewhere' outlook. I am an old C++ (and FORTRAN and Visual Foxpro) programmer. But I am new to boost, windows (MFC) and Visual Studio 2010. My challenge is to 'upgrade' a huge app (250 k lines of code) both Windows and Linux from boost 1.3.x (and stingray and .....) to boost 1.50 and win 7 ... Boost 1.50 is the last version our customer can use because of its 'private' version of Debian. I am first dealing with windows. When I compile the solution, I get a lot of errors and I would like you give me the first steps to do. Here is an example about file ...\boost\boost15\boost_1_50_0\boost/mpl/list/aux_/preprocessed/plain/list20.hpp list20.hpp(157): error C2143: syntax error : missing ',' before 'string' list20.hpp(163): error C2974: 'boost::mpl::list19' : invalid template argument for 'T18', type expected list20.hpp(144) : see declaration of 'boost::mpl::list19' list20.hpp(167) : see reference to class template instantiation 'boost::mpl::list20<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9,T10,T11,T12,T13,T14,T15,T16,T17,T18,__formal>' being compiled list20.hpp(164): error C3203: 'list19' : unspecialized class template can't be used as a template argument for template parameter 'Next', expected a real type list20.hpp(164): error C2955: 'boost::mpl::list19' : use of class template requires template argument list list20.hpp(144) : see declaration of 'boost::mpl::list19' list20.hpp(165): error C2955: 'boost::mpl::l_item' : use of class template requires template argument list So if you can explain me what is wrong (I mean I am astonished (?) to find a syntax error and I think I must not modify the file so the error may come from elsewhere ...) TIA Jean

2 3

[fiber] High CPU usage when fiber round robin sheduler is idle
by lin li 26 Sep '16

26 Sep '16

Hi, guys. I have a problem with Boost fiber in 1.62 beta 2. My machine is a 4 core machine with 64bit ubuntu 14.04 installed. In my program, I created 4 kernel threads each of which uses the round robin fiber scheduler. One thread 1, I created one fiber that read data from a socket in a blocking manner. Once it got some data, it writes the data into a blocking fiber channel. For the rest thread kernel threads, I created 5 fibers for each of them. They all read (in a blocking manner) data from the same channel. My problem is when no data is sent to the socket, and the system is idling, I can see very high CPU usage on three cores. I profiled the code, it seems to me that the kernel threads keep calling fiber scheduler to sleep then wake up again. I suspect that the time interval for the function suspend_until() may be too short. If that is the case, then how can I increase it?

2 1

[serialization] Runtime overhead of serialization archives
by georg＠schorsch-tech.de 25 Sep '16

25 Sep '16

Hi all, currently i try to measure the runtime overhead of serialization vs. plain c-style serialization. The goal is to send it from one process to an other process on the same machine. As my statemachines are written with boost::msm, i want to deliver types. For the IPC i used interprocess::message_queue. I wrote a template function for the test and added a trait to plug in the test functions. I tested on the same machine, once with Linux Debian stretch x64 and Win 10 x64 MSVC 2015. What really astonish me is the fact, that the measured times using boost::serilization is so high compared to "c-style: id + data" method. In the c-style method i used a FNV hash of the type name as the ID. All tests were done on a Intel Core i7 2670QM CPU. All results in sec. I sent/received 100000 objects over a message_queue. Boost 1.61.0 Linux x86_64 / gcc 6.1.1 Win 10 x64/ MSVC 2015 Boost XML Send 2.220753 8.255834 Boost XML Receive 3.208353 10.14462 Boost Text Send 2.024946 8.578654 Boost Text Receive 3.207359 10.704126 Boost BinarySend 2.018026 8.363865 Boost Binary Receive 3.17984 11.201501 Cstyle Send 0.13566 0.056814 Cstyle Receive 0.087906 0.058706 Char Send 0.071683 0.013965 Char Receive 0.062119 0.012631 To measure the real overhead of the message passing, i made a test and just sent 100000 plain chars over the "wire". There are two strange things: a) The serilization with boost seems to be about 16 times slower than the plain c-style method, the receive seems to be about 30 times slower. I think i do something wrong..... he tests were compiled on release mode. b) On the same hardware, the Windows implementation is so much slower than the Linux one... about factor 3. But at the c-style method, it turns around.... Linux is slower than Windows. Has anyone an idea whats the issue here? I added the code at the end of this text Best regards Georg // ----------------------------------------------------- // Code // ----------------------------------------------------- #define BOOST_TEST_MODULE first_tests #include <boost/test/unit_test.hpp> #include <boost/interprocess/ipc/message_queue.hpp> // send all data through this #include <boost/timer/timer.hpp> // measure the used time #include <iostream> // for output // STL Archive + Stuff #include <boost/serialization/base_object.hpp> #include <boost/serialization/export.hpp> #include <boost/serialization/shared_ptr.hpp> #include <boost/serialization/unique_ptr.hpp> // include headers that implement a archive in xml format #include <boost/archive/archive_exception.hpp> #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/binary_iarchive.hpp> #include <boost/archive/binary_oarchive.hpp> #include <boost/iostreams/device/array.hpp> #include <boost/iostreams/device/back_inserter.hpp> #include <boost/iostreams/stream.hpp> #include <memory> #include <stdint.h> #include <typeinfo> #include <vector> using namespace boost::interprocess; static const int test_count = 100000; // send this many structs // the test structure struct ev_test { long a = 1; unsigned long b = 2; }; // ---------------------------------------------------------------------------- // a packet on the wire // ---------------------------------------------------------------------------- using packet = std::vector<char>; //----------------------------------------------------------------------------- // Type carrier and its support // ---------------------------------------------------------------------------- namespace { class carrier_visitor_base; class carrier_base // the base in the queue { public: using ptr = std::unique_ptr<carrier_base>; virtual ~carrier_base() {} virtual void accept(carrier_visitor_base *p_visitor) = 0; template <class Archive> void serialize(Archive &ar, const unsigned int version) { } }; template <typename T> class carrier; class carrier_visitor_base { public: virtual ~carrier_visitor_base() {} virtual void handle(carrier<ev_test> *p_evt) = 0; virtual void handle(carrier<char> *p_evt) = 0; }; template <typename T> class carrier : public carrier_base // the specific carrier { public: explicit carrier() : m_data() {} explicit carrier(const T &data) : m_data(data) {} virtual void accept(carrier_visitor_base *p_visitor) override { p_visitor->handle(this); } T &data() { return m_data; } private: T m_data; }; } // ns anon // ---------------------------------------------------------------------------- // the traits for the chartest // ---------------------------------------------------------------------------- struct char_test { static const char *name() { return "char_test 'c': "; } static size_t msg_size() { return sizeof(char); } static char get_data() { return 'c'; } template <typename T> static packet to_wire(T data) { packet ret; ret.push_back(get_data()); return ret; } static carrier_base::ptr from_wire(const packet &data) { auto p_data = new carrier<char>(); p_data->data() = data[0]; return std::unique_ptr<carrier<char>>(p_data); } }; // ---------------------------------------------------------------------------- // the traits for the boost xml serialization test // ---------------------------------------------------------------------------- // ---------------------------------------------------------------------------- // external serialization function // ---------------------------------------------------------------------------- namespace boost { namespace serialization { // serialization function for ev_test template <class Archive> inline void serialize(Archive &ar, ev_test &t, const unsigned int version) { ar &BOOST_SERIALIZATION_NVP(t.a); ar &BOOST_SERIALIZATION_NVP(t.b); } // serialization function for carrier<T> template <class Archive, typename T> void serialize(Archive &ar, carrier<T> &t, const unsigned int version) { ar &boost::serialization::make_nvp( "carrier_base", boost::serialization::base_object<carrier_base>(t)); // BOOST_SERIALIZATION_BASE_OBJECT_NVP(a); auto &data = t.data(); ar &BOOST_SERIALIZATION_NVP(data); } } } // we must export all carrier BOOST_SERIALIZATION_SHARED_PTR(carrier<ev_test>) BOOST_CLASS_EXPORT(carrier<ev_test>) struct boost_xml_trait { static const char *name() { return "boost_xml_test: ev_test: "; } typedef boost::archive::xml_oarchive oarchive; typedef boost::archive::xml_iarchive iarchive; }; struct boost_text_trait { static const char *name() { return "boost_text_test: ev_test: "; } typedef boost::archive::xml_oarchive oarchive; typedef boost::archive::xml_iarchive iarchive; }; struct boost_binary_trait { static const char *name() { return "boost_binary_test: ev_test: "; } typedef boost::archive::xml_oarchive oarchive; typedef boost::archive::xml_iarchive iarchive; }; template <typename archive_trait> struct boost_test { static const char *name() { return archive_trait::name(); } static size_t msg_size() { return 600; } // throws boost::archive::archive_exception template <typename T> static packet to_wire(T data) { using namespace boost::iostreams; using T1 = typename std::remove_cv<T>::type; using BT = typename std::remove_reference<T1>::type; carrier_base::ptr p_carrier = std::make_unique<carrier<BT>>(data); packet p; { back_insert_device<packet> sink{ p }; stream<back_insert_device<packet>> os{ sink }; typename archive_trait::oarchive oa(os); oa << BOOST_SERIALIZATION_NVP(p_carrier); } return p; } // throws boost::archive::archive_exception static carrier_base::ptr from_wire(const packet &data) { using namespace boost::iostreams; carrier_base::ptr p_carrier; boost::iostreams::array_source source{ data.data(), data.size() }; stream<array_source> is{ source }; typename archive_trait::iarchive ia(is); // this takes the most time ia >> BOOST_SERIALIZATION_NVP(p_carrier); return p_carrier; } }; // ---------------------------------------------------------------------------- // the traits for the cstyle serialization test // ---------------------------------------------------------------------------- // ---------------------------------------------------------------------------- // cstyle serialization with fnv type identifier // ---------------------------------------------------------------------------- struct cstyle_test { static const char *name() { return "cstyle_test: "; } static size_t msg_size() { return 1000; } // FowlerNollVo hash function // https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function struct fnv { const static uint64_t base = 0xcbf29ce484222325; const static uint64_t prime = 0x00000100000001b3; const static uint64_t next(uint64_t current, size_t char_code) { return (current ^ char_code) * prime; } const static uint64_t value(const char *cptr, uint64_t interim = base) { return (*cptr == '\0') ? interim : value(cptr + 1, next(interim, static_cast<size_t>(*cptr))); } }; template <typename T> static packet to_wire(T data) { packet buffer(msg_size()); // to be fair, send the same amount of bytes const uint64_t id = fnv::value(typeid(T).name()); size_t pos = 0; assert(msg_size() >= sizeof(uint64_t) + sizeof(T)); // buffer.resize(buffer.size() + sizeof(uint64_t) + sizeof(T)); std::memcpy(buffer.data() + pos, &id, sizeof(uint64_t)); pos += sizeof(uint64_t); std::memcpy(buffer.data() + pos, &data, sizeof(T)); pos += sizeof(T); return buffer; } static carrier_base::ptr from_wire(const packet &data) { // get the id size_t pos = 0; uint64_t id; std::memcpy(&id, data.data() + pos, sizeof(uint64_t)); pos += sizeof(uint64_t); // create the specific pointer if (id == fnv::value(typeid(ev_test).name())) { assert(data.size() >= sizeof(uint64_t) + sizeof(ev_test)); auto p_evt = new carrier<ev_test>(); std::memcpy(&p_evt->data(), data.data() + pos, sizeof(ev_test)); return carrier_base::ptr(p_evt); } throw std::runtime_error("deserialize error"); } }; template <typename trait> void do_test() { class runtime : public carrier_visitor_base { public: virtual void handle(carrier<ev_test> *p_evt) override { i += p_evt->data().a; } virtual void handle(carrier<char> *p_evt) override { i += p_evt->data(); } int i = 0; }; try { std::cout << "Sending " << trait::name() << test_count << std::endl; // Erase previous message queue message_queue::remove("message_queue"); // Create a message_queue. message_queue mq(create_only // only create , "message_queue" // name , test_count // max message number , trait::msg_size() // max message size ); // send ev_tests boost::timer::auto_cpu_timer t; for (int i = 0; i < test_count; ++i) { auto buffer = trait::to_wire(ev_test()); mq.send(buffer.data(), buffer.size(), 0); } } catch (const interprocess_exception &ex) { message_queue::remove("message_queue"); std::cout << ex.what() << std::endl; BOOST_CHECK(true == false); } runtime rt; try { std::cout << "Receiving " << trait::name() << test_count << std::endl; // Open a message queue. message_queue mq(open_only // only create , "message_queue" // name ); message_queue::size_type recvd_size; packet buffer(trait::msg_size()); unsigned int priority; boost::timer::auto_cpu_timer t; for (int i = 0; i < test_count; ++i) { // receive the raw data mq.receive(buffer.data(), buffer.size(), recvd_size, priority); // deserialize auto p_carrier = trait::from_wire(buffer); // handle it to the protocol p_carrier->accept(&rt); } } catch (const interprocess_exception &ex) { message_queue::remove("message_queue"); std::cout << ex.what() << std::endl; BOOST_CHECK(true == false); } message_queue::remove("message_queue"); std::cout << "RT Counter: " << rt.i << std::endl << std::endl; } BOOST_AUTO_TEST_CASE(carrier_boost_xml_ev_test) { do_test<boost_test<boost_xml_trait>>(); } BOOST_AUTO_TEST_CASE(carrier_boost_text_ev_test) { do_test<boost_test<boost_text_trait>>(); } BOOST_AUTO_TEST_CASE(carrier_boost_binary_ev_test) { do_test<boost_test<boost_binary_trait>>(); } BOOST_AUTO_TEST_CASE(carrier_cstyle_ev_test) { do_test<cstyle_test>(); } BOOST_AUTO_TEST_CASE(carrier_char_test) { do_test<char_test>(); }

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[boost][multiprecision] compile error with gcc 4.8.4
by Rob Conde 24 Sep '16

24 Sep '16

Please see the scenario below...am I doing something wrong or is this a gcc or multiprecision bug? Thanks, Rob Conde given the following code (multiPrecisionTest.cpp): #include <boost/multiprecision/cpp_int.hpp> #include <boost/multiprecision/cpp_bin_float.hpp> typedef boost::multiprecision::int128_t int128_t; typedef boost::multiprecision::cpp_bin_float_quad float128_t; int main() { int128_t intVal; float128_t floatVal(intVal.convert_to<float128_t>()); return 0; } -------------------------------------------------------------------------- g++ -std=c++0x -c multiPrecisionTest.cpp I get the following error: In file included from ./boost/multiprecision/cpp_int.hpp:1936:0, from multiPrecisionTest.cpp:1: ./boost/multiprecision/cpp_int/misc.hpp: In instantiation of ‘typename boost::enable_if_c<(boost::multiprecision::backends::is_trivial_cpp_int<boost::multiprecision::backends::cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && boost::multiprecision::is_signed_number<boost::multiprecision::backends::cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value)>::type boost::multiprecision::backends::eval_convert_to(R*, const boost::multiprecision::backends::cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>&) [with R = boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<113u, (boost::multiprecision::backends::digit_base_type)2u, void, short int, -16382, 16383>, (boost::multiprecision::expression_template_option)0u>; unsigned int MinBits1 = 128u; unsigned int MaxBits1 = 128u; boost::multiprecision::cpp_integer_type SignType1 = (boost::multiprecision::cpp_integer_type)1u; boost::multiprecision::cpp_int_check_type Checked1 = (boost::multiprecision::cpp_int_check_type)0u; Allocator1 = void; typename boost::enable_if_c<(boost::multiprecision::backends::is_trivial_cpp_int<boost::multiprecision::backends::cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && boost::multiprecision::is_signed_number<boost::multiprecision::backends::cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value)>::type = void]’: ./boost/multiprecision/number.hpp:585:40: required from ‘void boost::multiprecision::number<Backend, ExpressionTemplates>::convert_to_imp(T*) const [with T = boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<113u, (boost::multiprecision::backends::digit_base_type)2u, void, short int, -16382, 16383>, (boost::multiprecision::expression_template_option)0u>; Backend = boost::multiprecision::backends::cpp_int_backend<128u, 128u, (boost::multiprecision::cpp_integer_type)1u, (boost::multiprecision::cpp_int_check_type)0u, void>; boost::multiprecision::expression_template_option ExpressionTemplates = (boost::multiprecision::expression_template_option)0u]’ ./boost/multiprecision/number.hpp:601:29: required from ‘T boost::multiprecision::number<Backend, ExpressionTemplates>::convert_to() const [with T = boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<113u, (boost::multiprecision::backends::digit_base_type)2u, void, short int, -16382, 16383>, (boost::multiprecision::expression_template_option)0u>; Backend = boost::multiprecision::backends::cpp_int_backend<128u, 128u, (boost::multiprecision::cpp_integer_type)1u, (boost::multiprecision::cpp_int_check_type)0u, void>; boost::multiprecision::expression_template_option ExpressionTemplates = (boost::multiprecision::expression_template_option)0u]’ multiPrecisionTest.cpp:10:54: required from here ./boost/multiprecision/cpp_int/misc.hpp:533:138: error: no type named ‘type’ in ‘struct boost::common_type<boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<113u, (boost::multiprecision::backends::digit_base_type)2u, void, short int, -16382, 16383>, (boost::multiprecision::expression_template_option)0u>, __int128 unsigned>’ typedef typename common_type<R, typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::local_limb_type>::type common_type; ^

2 17

[Ranges] Range adaptors and range lifetimes
by Álex Puchades 24 Sep '16

24 Sep '16

Hi boost users! I'm having some lifetime issues with range adaptors. It seems boost adaptors (at least, transformed_range) only store iterators from the original range, letting it go out of scope [1]. Unfortunately, this makes boost adaptors not compatible with ranges that return iterators that are only valid while the original range is in scope (ie: any iterator that references the original range). This type of ranges are useful to avoid the fat-iterator problem, as seen here [2]. Is there any reason for the current behaviour? Should I file a bug or has it been discussed before? Thanks for your help [1] https://github.com/boostorg/range/blob/develop/include/boost/range/adaptor/… [2] http://ericniebler.com/2013/11/07/input-iterators-vs-input-ranges/ -- Álex Puchades

1 0

boost coroutine 1.62 b2 deprecation typo
by Jason Mancini 23 Sep '16

23 Sep '16

Just noticing that there's probably a typo in one of the deprecation warnings, as it wants both defined: BOOST_COROUTINE_NO_DEPRECATION_WARNING BOOST_COROUTINES_NO_DEPRECATION_WARNING Jason

1 0

[Parallel BGL] Poor scalability of dijkstra and delta stepping parallel graph algorithms
by Alexander Frolov 22 Sep '16

22 Sep '16

Hi! I am evaluating scalability on various graph algorithms and found that base parallel SSSP algorithms in PBGL does not scale well in my cases. The plots for rmat (scale=20 and 22) are attached. The source code for the benchmark are attached as well. The main issue that makes me think that I'm doing smth wrong is that execution time of delta stepping algorithm is _increasing_ with node number. I tried to check the code but has not found anything suspicious. Can anybody help me with this issue? Best, Alexander

1 0