+int reached(xbt_state_t st);
+void set_pair_reached(xbt_state_t st);
+int snapshot_compare(mc_snapshot_t s1, mc_snapshot_t s2);
+void MC_show_stack_liveness_stateful(xbt_fifo_t stack);
+void MC_dump_stack_liveness_stateful(xbt_fifo_t stack);
+void MC_pair_delete(mc_pair_t pair);
+void MC_exit_liveness(void);
+mc_state_t MC_state_pair_new(void);
+int visited(xbt_state_t st, int search_cycle);
+void set_pair_visited(xbt_state_t st, int search_cycle);
+int visited_hash(xbt_state_t st, int search_cycle);
+void set_pair_visited_hash(xbt_state_t st, int search_cycle);
+
+/* **** Double-DFS stateful without visited state **** */
+
+extern xbt_fifo_t mc_stack_liveness_stateful;
+
+void MC_ddfs_stateful_init(xbt_automaton_t a);
+void MC_ddfs_stateful(xbt_automaton_t a, int search_cycle, int restore);
+
+/* **** Double-DFS stateless **** */
+
+typedef struct s_mc_pair_stateless{