diff --git a/CHANGES.md b/CHANGES.md
index 9f625a7ad..5c1dfba19 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,8 @@
 # NEXT
 
+* Fix the development-profile build with recent compilers: anonymize
+  unused functor parameters in printer and functor signatures
+  (warning 67)
 * Fix typo `whitout` in type definition
 	(#324 by Martin @MBodin Bodin)
 * Add support for the clip-path presentation attribute
diff --git a/lib/html_f.mli b/lib/html_f.mli
index 647c57c49..4c3ae76eb 100644
--- a/lib/html_f.mli
+++ b/lib/html_f.mli
@@ -46,7 +46,7 @@ module Wrapped_functions
 (** Similar to {!Make} but with a custom set of wrapped functions. *)
 module Make_with_wrapped_functions
     (Xml : Xml_sigs.T)
-    (C : Html_sigs.Wrapped_functions with module Xml = Xml)
+    (_ : Html_sigs.Wrapped_functions with module Xml = Xml)
     (Svg : Svg_sigs.T with module Xml := Xml)
   : Html_sigs.Make(Xml)(Svg).T
     with type +'a elt = Xml.elt
diff --git a/lib/svg_f.mli b/lib/svg_f.mli
index 476c15fbe..0375f48e6 100644
--- a/lib/svg_f.mli
+++ b/lib/svg_f.mli
@@ -99,7 +99,7 @@ module Wrapped_functions
 (** Similar to {!Make} but with a custom set of wrapped functions. *)
 module Make_with_wrapped_functions
     (Xml : Xml_sigs.T)
-    (C : Svg_sigs.Wrapped_functions with module Xml = Xml)
+    (_ : Svg_sigs.Wrapped_functions with module Xml = Xml)
   : Svg_sigs.Make(Xml).T
     with type +'a elt = Xml.elt
      and type +'a attrib = Xml.attrib
diff --git a/lib/xml_print.mli b/lib/xml_print.mli
index 782fa56a7..54a5fc927 100644
--- a/lib/xml_print.mli
+++ b/lib/xml_print.mli
@@ -103,7 +103,7 @@ module type TagList = sig val emptytags : string list end
 (** Printers for raw XML modules. *)
 module Make_fmt
     (Xml : Xml_sigs.Iterable)
-    (I : TagList)
+    (_ : TagList)
   : Xml_sigs.Pp with type elt := Xml.elt
 
 (** {2 Deprecated functors}
@@ -113,7 +113,7 @@ module Make_fmt
 
 module Make
     (Xml : Xml_sigs.Iterable)
-    (I : TagList)
+    (_ : TagList)
     (O : Xml_sigs.Output)
   : Xml_sigs.Printer with type out := O.out and type xml_elt := Xml.elt
     [@@ocaml.deprecated "Use Xml_print.Make_fmt instead."]
@@ -129,7 +129,7 @@ module Make_typed
 
 module Make_simple
     (Xml : Xml_sigs.Iterable)
-    (I : TagList)
+    (_ : TagList)
   : Xml_sigs.Simple_printer with type xml_elt := Xml.elt
     [@@ocaml.deprecated "Use Xml_print.Make_fmt instead."]