diff --git a/test/unison/unison.ml b/test/unison/unison.ml
index 1d8ddc1e59faf31d47912d1e509f87742544ec7b..d489917dbae0a4520625cdd13ad95ebd67f85f7b 100644
--- a/test/unison/unison.ml
+++ b/test/unison/unison.ml
@@ -1,4 +1,4 @@
-(* Time-stamp: <modified the 07/03/2019 (at 11:31) by Erwan> *)
+(* Time-stamp: <modified the 07/03/2019 (at 14:06) by Erwan> *)
 
 open Algo
 
@@ -12,12 +12,13 @@ let list_min l =
     [] -> assert false
   | x::l -> List.fold_left min x l
 
+(* avoid warning when casting to int *)
 let i e v = match e v with I i -> i | _ -> assert false
 
 let new_clock_value nl e =
   let cl = List.map (fun n -> i n.lenv "clock") nl in
   let min_clock = List.fold_left min (i e "clock") cl in
-  min_clock + 1 mod m 
+  (min_clock + 1) mod m 
 
 let enable_f nl e =
   if I (new_clock_value nl e) <> e "clock" then ["incr"] else []