Bradley-Meyers-MacBook-Air:example bradleymeyer$ g++ --version
g++ (MacPorts gcc45 4.5.4_6) 4.5.4
Copyright (C) 2010 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Bradley-Meyers-MacBook-Air:example bradleymeyer$ g++ -I/Users/bradleymeyer/special/boost/boost-trunk/ -Wconversion -o test write_graphviz.cpp 
In file included from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/match_results.hpp:56:0,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/access.hpp:21,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/state.hpp:18,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/matcher/alternate_end_matcher.hpp:20,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/matchers.hpp:17,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/regex_primitives.hpp:22,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/xpressive_static.hpp:24,
                 from /Users/bradleymeyer/special/boost/boost-trunk/boost/graph/graphviz.hpp:34,
                 from write_graphviz.cpp:13:
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/utility/sequence_stack.hpp: In member function 'T* boost::xpressive::detail::sequence_stack<T>::grow_(size_t, const T&) [with T = boost::xpressive::detail::sub_match_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >, size_t = long unsigned int]':
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/utility/sequence_stack.hpp:216:40:   instantiated from 'T* boost::xpressive::detail::sequence_stack<T>::push_sequence(size_t, const T&) [with T = boost::xpressive::detail::sub_match_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >, size_t = long unsigned int]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/utility/sequence_stack.hpp:224:46:   instantiated from 'T* boost::xpressive::detail::sequence_stack<T>::push_sequence(size_t, const T&, boost::xpressive::detail::fill_t) [with T = boost::xpressive::detail::sub_match_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >, size_t = long unsigned int]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/state.hpp:292:9:   instantiated from 'void boost::xpressive::detail::match_state<BidiIter>::init_(const boost::xpressive::detail::match_state<BidiIter>::regex_impl&, boost::xpressive::detail::match_state<BidiIter>::match_results&) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, boost::xpressive::detail::match_state<BidiIter>::regex_impl = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >, boost::xpressive::detail::match_state<BidiIter>::match_results = boost::xpressive::match_results<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/core/state.hpp:161:9:   instantiated from 'boost::xpressive::detail::match_state<BidiIter>::match_state(BidiIter, BidiIter, boost::xpressive::detail::match_state<BidiIter>::match_results&, const boost::xpressive::detail::match_state<BidiIter>::regex_impl&, boost::xpressive::regex_constants::match_flag_type) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, boost::xpressive::detail::match_state<BidiIter>::match_results = boost::xpressive::match_results<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >, boost::xpressive::detail::match_state<BidiIter>::regex_impl = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> > >]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/regex_algorithms.hpp:62:97:   instantiated from 'bool boost::xpressive::detail::regex_match_impl(typename boost::mpl::identity<T>::type, typename boost::mpl::identity<T>::type, boost::xpressive::match_results<BidiIter>&, const boost::xpressive::basic_regex<BidiIter>&, boost::xpressive::regex_constants::match_flag_type) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, typename boost::mpl::identity<T>::type = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/regex_algorithms.hpp:261:64:   instantiated from 'bool boost::xpressive::regex_match(BidiRange&, const boost::xpressive::basic_regex<BidiIter>&, boost::xpressive::regex_constants::match_flag_type, typename boost::disable_if<boost::xpressive::detail::is_char_ptr<BidiRange> >::type*) [with BidiRange = std::basic_string<char>, BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, typename boost::disable_if<boost::xpressive::detail::is_char_ptr<BidiRange> >::type = void]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/graph/graphviz.hpp:71:5:   instantiated from 'std::string boost::escape_dot_string(const T&) [with T = std::basic_string<char>, std::string = std::basic_string<char>]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/graph/graphviz.hpp:262:5:   instantiated from 'void boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter, VertexID, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type) [with Graph = boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_color_t, boost::default_color_type>, boost::property<boost::edge_weight_t, int> >, VertexPropertiesWriter = boost::label_writer<const char**>, EdgePropertiesWriter = boost::default_writer, GraphPropertiesWriter = boost::default_writer, VertexID = boost::vec_adj_list_vertex_id_map<boost::property<boost::vertex_color_t, boost::default_color_type>, long unsigned int>, std::ostream = std::basic_ostream<char>, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type = boost::graph::detail::no_parameter]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/graph/graphviz.hpp:290:5:   instantiated from 'void boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type) [with Graph = boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_color_t, boost::default_color_type>, boost::property<boost::edge_weight_t, int> >, VertexPropertiesWriter = boost::label_writer<const char**>, EdgePropertiesWriter = boost::default_writer, GraphPropertiesWriter = boost::default_writer, std::ostream = std::basic_ostream<char>, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type = boost::graph::detail::no_parameter]'
/Users/bradleymeyer/special/boost/boost-trunk/boost/graph/graphviz.hpp:312:5:   instantiated from 'void boost::write_graphviz(std::ostream&, const Graph&, VertexWriter, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type) [with Graph = boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_color_t, boost::default_color_type>, boost::property<boost::edge_weight_t, int> >, VertexWriter = boost::label_writer<const char**>, std::ostream = std::basic_ostream<char>, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type = boost::graph::detail::no_parameter]'
write_graphviz.cpp:57:55:   instantiated from here
/Users/bradleymeyer/special/boost/boost-trunk/boost/xpressive/detail/utility/sequence_stack.hpp:118:114: warning: conversion to 'double' from 'size_t' may alter its value