Hint Rewrite @FF_sepcon @sepcon_FF : normalize.
Hint Rewrite @prop_true_andp using (solve [auto]) : normalize.

Lemma pure_con' {A} {JA: Join A}{PA: Perm_alg A}{SA: Sep_alg A}{agA: ageable A}{AgeA: Age_alg A}:
forall P Q, pure P -> pure Q -> pure (P*Q).