Definition isGlobalBlock {F V : Type} (ge : Genv.t F V) :=
  fun b => (fst (genv2blocksBool ge)) b || (snd (genv2blocksBool ge)) b.

Lemma intern_incr_meminj_preserves_globals: forall {F V} (ge: Genv.t F V) mu (PG: meminj_preserves_globals ge (extern_of mu) /\ (forall b, isGlobalBlock ge b = true -> frgnBlocksSrc mu b = true)) mu' (Inc: intern_incr mu mu'), meminj_preserves_globals ge (extern_of mu') /\ (forall b, isGlobalBlock ge b = true -> frgnBlocksSrc mu' b = true).