proposition: Lemma derives_nonexpansive_r: forall P Q n, approx n (weak_derives P Q) = approx n (weak_derives P (approx n Q)).
proof: Proof. repeat intro. apply (nonexpansive_super_non_expansive (fun Q => weak_derives P Q)); repeat intro. split; simpl; intros; eapply H3 in H7; try eassumption. - eapply H; auto. apply ext_level in H6, H2; apply necR_level in H1, H5. lia. - eapply H in H7; auto. apply ext_level in H6, H2; apply necR_level in H1, H5. lia. Qed.
imports: VST.veric.compcert_rmaps VST.msl.shares VST.msl.wand_frame VST.concurrency.conclib CertiGraph.lib.List_ext CertiGraph.msl_ext.log_normalize CertiGraph.msl_ext.ramification_lemmas CertiGraph.graph.graph_model CertiGraph.CertiGC.GCGraph CertiGraph.CertiGC.env_graph_gc CertiGraph.msl_ext.iter_sepcon Coq.Lists.List