diff --git a/src/arith/lra/linear_expr_intf.ml b/src/arith/lra/linear_expr_intf.ml
index 8a73c37b..14b7b619 100644
--- a/src/arith/lra/linear_expr_intf.ml
+++ b/src/arith/lra/linear_expr_intf.ml
@@ -134,7 +134,7 @@ module type S = sig
       to coefficients. This allows for very fast computations.
   *)
   module Comb : sig
-    type t = private C.t Var_map.t
+    type t
     (** The type of linear combinations. *)
 
     val compare : t -> t -> int