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 alloc_variables_fun: forall {ge e m vl e1 m1 e2 m2}, Clight.alloc_variables ge e m vl e1 m1 -> Clight.alloc_variables ge e m vl e2 m2 -> (e1,m1)=(e2,m2).