proposition: Lemma derives_nonexpansive: forall P Q n, approx n (weak_derives P Q) = approx n (weak_derives (approx n P) (approx n Q)).
proof: Proof. apply nonexpansive2_super_non_expansive; intros. - split; simpl; intros; (assert (a >= level a''0)%nat; [ | eapply H; eauto]); apply ext_level in H6, H2; apply necR_level in H1, H5; lia. - split; simpl; intros; (assert (a >= level a''0)%nat; [ | eapply H in H7 ; eauto]); 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