Definition var_name (V: Type) (bdec: ident * globvar V) : ident :=
   fst bdec.Definition no_dups (F V: Type) (fdecs: list (ident * F)) (bdecs: list (ident * globvar V)) : Prop :=
  list_norepet (map (@fst ident F) fdecs ++ map (@var_name V) bdecs).

Lemma deref_loc_fun: forall {ty m b z v v'}, Clight.deref_loc ty m b z v -> Clight.deref_loc ty m b z v' -> v=v'.