proposition: Lemma prop_impl_imp: forall (P Q: Prop), !! (P -> Q) = !! P --> !! Q.
proof: Proof. intros. apply pred_ext. + apply imp_andp_adjoint. normalize. + apply prop_imp_prop_left. Qed.
imports: CertiGraph.lib.Coqlib CertiGraph.lib.Ensembles_ext CertiGraph.lib.List_ext VST.msl.Extensionality VST.msl.simple_CCC VST.msl.seplog VST.msl.log_normalize Coq.Lists.List Coq.Sorting.Permutation Coq.Classes.Morphisms CertiGraph.msl_ext.seplog CertiGraph.msl_ext.log_normalize