diff --git a/src/sat/Solver.ml b/src/sat/Solver.ml
index ef7d5f75..150ccf1a 100644
--- a/src/sat/Solver.ml
+++ b/src/sat/Solver.ml
@@ -347,7 +347,7 @@ module Make (Plugin : PLUGIN) = struct
 
         (* allocate space *)
         (let new_len = cid + 1 in
-         Vec.ensure_size c_lits [||] new_len;
+         Vec.ensure_size c_lits ~elt:[||] new_len;
          Vec_float.ensure_size c_activity new_len;
          Step_vec.ensure_size c_proof new_len;
          Bitvec.ensure_size c_attached new_len;
diff --git a/src/util/Backtrack_stack.ml b/src/util/Backtrack_stack.ml
index 244fe6ee..60f9c423 100644
--- a/src/util/Backtrack_stack.ml
+++ b/src/util/Backtrack_stack.ml
@@ -23,4 +23,4 @@ let pop_levels (self : _ t) (n : int) ~f : unit =
     Vec.shrink self.lvls new_lvl
   )
 
-let iter ~f self = Vec.iter f self.vec
+let iter ~f self = Vec.iter ~f self.vec