Hi, I'm new to Boost and I've decided to use it in my C++ project. My first attempt is to use boost::program_options. However, Im hitting a slag and I can't figure out whats the problem. ive got this: #include "boost/program_options.hpp" int main() { return 0; } then I run: g++ -I/usr/local/include -L/usr/local/lib test.cpp but I get this error that doesn't make any sense to me: In file included from /usr/local/include/boost/program_options/value_semantic.hpp:14, from /usr/local/include/boost/program_options/options_description.hpp:13, from /usr/local/include/boost/program_options.hpp:15, from test.cpp:1: /usr/local/include/boost/type_traits/is_unsigned.hpp: In instantiation of 'boost::detail::is_ununsigned_helper<short int>': /usr/local/include/boost/type_traits/is_unsigned.hpp:73: instantiated from 'boost::detail::is_unsigned_imp<short int>' /usr/local/include/boost/type_traits/is_unsigned.hpp:123: instantiated from 'boost::is_unsigned<short int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:110: instantiated from 'boost::detail::make_unsigned_imp<short int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:130: instantiated from 'boost::make_unsigned<short int>' /usr/local/include/boost/lexical_cast.hpp:846: instantiated from here /usr/local/include/boost/type_traits/is_unsigned.hpp:40: warning: comparison between 'enum boost::detail::is_unsigned_values<short int>::<anonymous>' and 'enum boost::detail::is_unsigned_values<short int>::<anonymous>' /usr/local/include/boost/type_traits/is_unsigned.hpp: In instantiation of 'boost::detail::is_ununsigned_helper<int>': /usr/local/include/boost/type_traits/is_unsigned.hpp:73: instantiated from 'boost::detail::is_unsigned_imp<int>' /usr/local/include/boost/type_traits/is_unsigned.hpp:123: instantiated from 'boost::is_unsigned<int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:110: instantiated from 'boost::detail::make_unsigned_imp<int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:130: instantiated from 'boost::make_unsigned<int>' /usr/local/include/boost/lexical_cast.hpp:860: instantiated from here /usr/local/include/boost/type_traits/is_unsigned.hpp:40: warning: comparison between 'enum boost::detail::is_unsigned_values<int>::<anonymous>' and 'enum boost::detail::is_unsigned_values<int>::<anonymous>' /usr/local/include/boost/type_traits/is_unsigned.hpp: In instantiation of 'boost::detail::is_ununsigned_helper<long int>': /usr/local/include/boost/type_traits/is_unsigned.hpp:73: instantiated from 'boost::detail::is_unsigned_imp<long int>' /usr/local/include/boost/type_traits/is_unsigned.hpp:123: instantiated from 'boost::is_unsigned<long int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:110: instantiated from 'boost::detail::make_unsigned_imp<long int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:130: instantiated from 'boost::make_unsigned<long int>' /usr/local/include/boost/lexical_cast.hpp:874: instantiated from here /usr/local/include/boost/type_traits/is_unsigned.hpp:40: warning: comparison between 'enum boost::detail::is_unsigned_values<long int>::<anonymous>' and 'enum boost::detail::is_unsigned_values<long int>::<anonymous>' /usr/local/include/boost/type_traits/is_unsigned.hpp: In instantiation of 'boost::detail::is_ununsigned_helper<long long int>': /usr/local/include/boost/type_traits/is_unsigned.hpp:73: instantiated from 'boost::detail::is_unsigned_imp<long long int>' /usr/local/include/boost/type_traits/is_unsigned.hpp:123: instantiated from 'boost::is_unsigned<long long int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:110: instantiated from 'boost::detail::make_unsigned_imp<long long int>' /usr/local/include/boost/type_traits/make_unsigned.hpp:130: instantiated from 'boost::make_unsigned<long long int>' /usr/local/include/boost/lexical_cast.hpp:889: instantiated from here /usr/local/include/boost/type_traits/is_unsigned.hpp:40: warning: comparison between 'enum boost::detail::is_unsigned_values<long long int>::<anonymous>' and 'enum boost::detail::is_unsigned_values<long long int>::<anonymous>' I tried including other libraries like foreach and thread and they compile & link fine. Can someone please help me? Thanks, Petr