remark a TODO for later

barrier/lifting.v

@@ -21,6 +21,8 @@ Lemma wp_alloc_pst E σ e v Q :
   (ownP σ ★ ▷ (∀ l, ■(σ !! l = None) ∧ ownP (<[l:=v]>σ) -★ Q (LocV l)))
        ⊑ wp E (Alloc e) Q.
 Proof.
+  (* TODO RJ: Without the set, ssreflect rewrite doesn't work. Figure out why or
+     reprot a bug. *)
   intros. set (φ v' σ' := ∃ l, v' = LocV l ∧ σ' = <[l:=v]>σ ∧ σ !! l = None).
   rewrite -(wp_lift_atomic_step (Alloc e) φ σ) // /φ;
     last by intros; inv_step; eauto 8.