I successfully compiled my program with GCC 3.2.3 on a Linux (Red Hat Linux 3.2.3-56) box. When I tried to compile the same program with GCC 3.4.4 on a Solaris box, it gave me the following errors. Can anyone help me figure out why it is happening? #g++ -O -I./boost_1_25_1 -Wall -o dfssearch.cpp dfssearch.cpp ./boost_1_25_1/boost/config/compiler/gcc.hpp:57:7: warning: #warning "Unknown compiler version - please run the configu re tests and report the results" In file included from ./boost_1_25_1/boost/graph/graph_utility.hpp:42, from ./boost_1_25_1/boost/graph/detail/adjacency_list.hpp:43, from ./boost_1_25_1/boost/graph/adjacency_list.hpp:293, from beaconfsa.cpp:19: ./boost_1_25_1/boost/graph/depth_first_search.hpp: In function `void boost::depth_first_search(const VertexListGraph&, const boost::bgl_named_params&)': ./boost_1_25_1/boost/graph/depth_first_search.hpp:167: error: there are no arguments to `make_dfs_visitor' that depend on a template parameter, so a declaration of `make_dfs_visitor' must be available ./boost_1_25_1/boost/graph/depth_first_search.hpp:167: error: (if you use `-fpermissive', G++ will accept your code, bu t allowing the use of an undeclared name is deprecated) In file included from ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp:39, from beaconfsa.cpp:22: ./boost_1_25_1/boost/pending/mutable_queue.hpp: In member function `bool boost::mutable_queue::test()': ./boost_1_25_1/boost/pending/mutable_queue.hpp:131: error: `is_heap' is not a member of `std' In file included from beaconfsa.cpp:22: ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp: In member function `void boost::dijkstra_visitor<Visitors>::edg e_relaxed(Edge, Graph&)': ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp:70: error: `m_vis' undeclared (first use this function) ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp:70: error: (Each undeclared identifier is reported only once for each function it appears in.) ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp: In member function `void boost::dijkstra_visitor<Visitors>::edg e_not_relaxed(Edge, Graph&)': ./boost_1_25_1/boost/graph/dijkstra_shortest_paths.hpp:74: error: `m_vis' undeclared (first use this function) beaconfsa.cpp: In function `int transition_fsa(unsigned int*, unsigned int*)': beaconfsa.cpp:282: warning: comparison between signed and unsigned integer expressions make: *** [beaconfsa.o] Error 1 _________________________________________________________________ Windows Live Spaces is here! It’s easy to create your own personal Web site. http://spaces.live.com/signup.aspx