diff --git a/src/kernel_services/ast_queries/logic_env.ml b/src/kernel_services/ast_queries/logic_env.ml
index 9ba7c2a34f2ed8a53bad27d6c705a308836d8eda..cee9bf044d5529321e5c238e99371303e9db38a1 100644
--- a/src/kernel_services/ast_queries/logic_env.ml
+++ b/src/kernel_services/ast_queries/logic_env.ml
@@ -317,7 +317,7 @@ let builtin_states =
   [ Logic_builtin.self; Logic_type_builtin.self; Logic_ctor_builtin.self ]
 
 module Builtins= struct
-  include Hook.Make(struct end)
+  include Hook.Make()
   (* ensures we do not apply the hooks twice *)
   module Applied =
     State_builder.False_ref
diff --git a/src/kernel_services/cmdline_parameters/cmdline.ml b/src/kernel_services/cmdline_parameters/cmdline.ml
index 8e8917faa9749ef2eb6661dc5c3cf73db343f158..019989e9ef1e26ecdd7c8267668b9a04f5b22917 100644
--- a/src/kernel_services/cmdline_parameters/cmdline.ml
+++ b/src/kernel_services/cmdline_parameters/cmdline.ml
@@ -158,7 +158,7 @@ let protect = function
 (** {2 Exiting Frama-C} *)
 (* ************************************************************************* *)
 
-module NormalExit = Hook.Make(struct end)
+module NormalExit = Hook.Make()
 let at_normal_exit = NormalExit.extend
 let run_normal_exit_hook = NormalExit.apply
 
@@ -617,7 +617,7 @@ struct
   let nb_actions = ref 0
   let is_going_to_run () = incr nb_actions
 
-  module H = Hook.Make(struct end)
+  module H = Hook.Make()
 
   let () = H.extend Log.treat_deferred_error
 
diff --git a/src/kernel_services/plugin_entry_points/db.ml b/src/kernel_services/plugin_entry_points/db.ml
index 69383faea0bdae2dd7329a0d55062024fac86df0..76c8222d724d27a819828530e4510964c0f8bd99 100644
--- a/src/kernel_services/plugin_entry_points/db.ml
+++ b/src/kernel_services/plugin_entry_points/db.ml
@@ -37,7 +37,7 @@ let register_guarded_compute is_computed r f =
   r := compute
 
 module Main = struct
-  include Hook.Make(struct end)
+  include Hook.Make()
   let play = mk_fun "Main.play"
 end
 
diff --git a/src/libraries/project/project.ml b/src/libraries/project/project.ml
index c0acfdff8947452331f840db6117e8ade36a124b..c2be72957be9a316bc382208c028fb7adb99e5c8 100644
--- a/src/libraries/project/project.ml
+++ b/src/libraries/project/project.ml
@@ -435,13 +435,13 @@ let clear_all () =
 
 exception IOError = Sys_error
 
-module Before_load = Hook.Make(struct end)
+module Before_load = Hook.Make()
 let register_before_load_hook = Before_load.extend
 
-module After_load = Hook.Make(struct end)
+module After_load = Hook.Make()
 let register_after_load_hook = After_load.extend
 
-module After_global_load = Hook.Make(struct end)
+module After_global_load = Hook.Make()
 let register_after_global_load_hook = After_global_load.extend
 
 let magic = 9 (* magic number *)
diff --git a/src/plugins/e-acsl/src/libraries/gmp_types.ml b/src/plugins/e-acsl/src/libraries/gmp_types.ml
index 9e23d23a5d478b7bd2e6e590a37a2691f83143d4..965406bdc339c1d6e6260f46ff971452e4f58e83 100644
--- a/src/plugins/e-acsl/src/libraries/gmp_types.ml
+++ b/src/plugins/e-acsl/src/libraries/gmp_types.ml
@@ -76,8 +76,8 @@ module Make() = struct
 
 end
 
-module Z = Make(struct end)
-module Q = Make(struct end)
+module Z = Make()
+module Q = Make()
 
 let bitcnt_type_info_ref = mk_dummy_type_info_ref ()
 
diff --git a/src/plugins/gui/gtk_helper.ml b/src/plugins/gui/gtk_helper.ml
index 7ca273c4caa42910c0f3909f27ce949ff3eaadcf..20df4ae960110acfb74801ce47b078f327453203 100644
--- a/src/plugins/gui/gtk_helper.ml
+++ b/src/plugins/gui/gtk_helper.ml
@@ -287,7 +287,7 @@ module Lock = struct
 end
 module Unlock = struct
   let first = ref (fun () -> ())
-  module H = Hook.Make(struct end)
+  module H = Hook.Make()
   let extend is_first f = if is_first then first := f else H.extend f
   let apply () = !first (); H.apply ()
 end
diff --git a/src/plugins/gui/launcher.ml b/src/plugins/gui/launcher.ml
index 138bce2502e143f5098ed3a6d3b149f8f7e22952..e6d9dbf1fb4883606dc28c0c1faea373ba7978c9 100644
--- a/src/plugins/gui/launcher.ml
+++ b/src/plugins/gui/launcher.ml
@@ -22,7 +22,7 @@
 
 open Gtk_helper
 
-module Kernel_hook = Hook.Make(struct end)
+module Kernel_hook = Hook.Make()
 
 class type basic_main = object
   inherit host