-extern XBT_PRIVATE xbt_dynar_t visited_states;
-XBT_PRIVATE simgrid::mc::VisitedState* is_visited_state(mc_state_t graph_state);
+extern XBT_PRIVATE std::vector<std::unique_ptr<simgrid::mc::VisitedState>> visited_states;
+XBT_PRIVATE std::unique_ptr<simgrid::mc::VisitedState> is_visited_state(mc_state_t graph_state);