Fixed to work in Coq 8.4, too

Frap.v

@@ -43,8 +43,12 @@ Ltac invert0 e := invert e; fail.
 Ltac invert1 e := invert0 e || (invert e; []).
 Ltac invert2 e := invert1 e || (invert e; [|]).
 
-Ltac simplify := repeat progress (simpl in *; intros; try autorewrite with core in *; repeat unifyTails);
-                                  repeat (removeDups || doSubtract).
+Ltac simplify := repeat (unifyTails; pose proof I);
+                repeat match goal with
+                       | [ H : True |- _ ] => clear H
+                       end;
+                repeat progress (simpl in *; intros; try autorewrite with core in *);
+                                 repeat (removeDups || doSubtract).
 Ltac propositional := intuition idtac.
 
 Ltac linear_arithmetic := intros;

ModelChecking.v

@@ -248,7 +248,7 @@ Ltac model_check_infer :=
   apply multiStepClosure_ok; simplify; model_check_steps.
 
 Ltac model_check_find_invariant :=
-  simplify; eapply invariant_weaken; [ model_check_infer | ].
+  simplify; eapply invariant_weaken; [ model_check_infer | ]; cbv beta in *.
 
 Ltac model_check := model_check_find_invariant; model_check_finish.
 

Sets.v

@@ -169,9 +169,22 @@ Proof.
   unfold constant; intuition eauto using removeDups_fwd, removeDups_bwd.
 Qed.
 
+Ltac someMatch ls :=
+  match ls with
+  | ?x :: ?ls' =>
+    let rec someMatch' ls :=
+        match ls with
+        | x :: _ => idtac
+        | _ :: ?ls' => someMatch' ls'
+        end
+    in someMatch' ls'
+  | _ :: ?ls' => someMatch ls'
+  end.
+
 Ltac removeDups :=
   match goal with
   | [ |- context[constant ?ls] ] =>
+    someMatch ls;
     erewrite (@removeDups_ok _ ls)
       by repeat (apply RdNil
                  || (apply RdNew; [ simpl; intuition congruence | ])