undefined reference to `std::char_traits<unsigned char>::length(unsigned char const*)'
undefined reference to `std::char_traits<unsigned char>::copy(unsigned char*, unsigned char const*, unsigned)'
undefined reference to `std::char_traits<unsigned char>::move(unsigned char*, unsigned char const*, unsigned)'
undefined reference to `std::char_traits<unsigned char>::copy(unsigned char*, unsigned char const*, unsigned)'
undefined reference to `std::char_traits<unsigned char>::copy(unsigned char*, unsigned char const*, unsigned)'
undefined reference to `std::char_traits<unsigned char>::move(unsigned char*, unsigned char const*, unsigned)'
undefined reference to `std::char_traits<unsigned char>::copy(unsigned char*, unsigned char const*, unsigned)'
です