Definition ret0_tycon (Delta: tycontext): tycontext :=
mk_tycontext (PTree.empty _) (PTree.empty _) (ret_type Delta) (glob_types Delta) (glob_specs Delta) (annotations Delta).
Definition ret1_tycon (Delta: tycontext): tycontext :=
mk_tycontext (PTree.set ret_temp (ret_type Delta) (PTree.empty _))
(PTree.empty _) (ret_type Delta) (glob_types Delta) (glob_specs Delta) (annotations Delta).

Lemma make_args0_tc_environ: forall rho Delta,
tc_environ Delta rho ->
tc_environ (ret0_tycon Delta) (make_args nil nil rho).