Definition maybe_retval (Q: environ -> mpred) retty ret :=
match ret with
| Some id => fun rho => Q (get_result1 id rho)
| None =>
match retty with
| Tvoid => (fun rho => Q (globals_only rho))
| _ => fun rho => EX v: val, Q (make_args (ret_temp::nil) (v::nil) rho)
end
end.

Lemma age_juicy_mem_i:
forall jm jm', m_dry jm = m_dry jm' ->
age (m_phi jm) (m_phi jm') ->
age jm jm'.