/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_function.h: In member function ‘bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = boost::tuples::tuple<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, short unsigned int, short int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>]’:
/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_map.h:347:   instantiated from ‘_Tp& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const _Key&) [with _Key = boost::tuples::tuple<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, short unsigned int, short int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, _Tp = std::pair<TTF_Font*, int>, _Compare = std::less<boost::tuples::tuple<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, short unsigned int, short int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type> >, _Alloc = std::allocator<std::pair<const boost::tuples::tuple<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, short unsigned int, short int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, std::pair<TTF_Font*, int> > >]’
sdl_fonts.cpp:258:   instantiated from here
/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_function.h:227: error: no match for ‘operator<’ in ‘__x < __y’