[Boost-users] error:void* is not a pointer-to-object type

Hi I tried to compile this example: typedef boost::adjacency_list Graph; typedef boost::graph_traits<Graph>::vertex_descriptor v_des; typedef boost::graph_traits<Graph>::vertex_iterator v_iter; typedef boost::graph_traits<Graph>::edge_descriptor e_des; typedef boost::graph_traits<Graph>::edge_iterator e_iter; Graph newg; ......// insert data in newg v_iter vit, ve; int index = 0; for(boost::tie(vit,ve)=boost::vertices(newg); vit!=ve; ++vit ){ v_des vd = *vit; vd->id()= index++; } but the reply is: "void*" is not a pointer-to-object type at the last line. What kind of error it is?? How can I solve this problem?? Thanks Best regards -Bombielfil-