proposition: Lemma no_edge2gen_bep: forall g roots from to, sound_gc_graph g -> gen2gen_no_edge g to from -> backward_edge_prop g roots from to.
proof: Proof. intros. red in H0 |-* . intros. destruct e as [[gen vidx] eidx]. simpl in *. subst gen. destruct H as [_ [? _]]. red in H. rewrite H in H1. apply H0 in H1. unfold VType in *. now rewrite H3 in H1. Qed.
imports: Coq.ZArith.ZArith Coq.Program.Basics compcert.lib.Integers compcert.common.Values VST.veric.base VST.veric.Clight_lemmas VST.veric.val_lemmas VST.veric.shares VST.msl.seplog VST.msl.shares VST.zlist.sublist VST.floyd.coqlib3 VST.floyd.functional_base VST.floyd.data_at_rec_lemmas CertiGraph.lib.Coqlib CertiGraph.lib.EquivDec_ext CertiGraph.lib.List_ext CertiGraph.graph.graph_model CertiGraph.graph.graph_gen CertiGraph.graph.path_lemmas CertiGraph.graph.subgraph2 CertiGraph.graph.graph_relation CertiGraph.graph.graph_isomorphism CertiGraph.graph.reachable_ind CertiGraph.CertiGC.GCGraph