diff --git a/src/kernel_services/ast_data/cil_types.mli b/src/kernel_services/ast_data/cil_types.mli
index c550806aaab96422e193ca33ed092fe8e4fca01e..f0eb6d86d0a0ea8d55cd9ac567a80295ffca5f28 100644
--- a/src/kernel_services/ast_data/cil_types.mli
+++ b/src/kernel_services/ast_data/cil_types.mli
@@ -1487,7 +1487,7 @@ and logic_body =
 (** Description of a logic type.
     @plugin development guide *)
 and logic_type_info = {
-  lt_name: string;
+  mutable lt_name: string;
   lt_params : string list; (** type parameters*)
   mutable lt_def: logic_type_def option;
     (** definition of the type. None for abstract types. *)
@@ -1528,7 +1528,7 @@ and logic_var = {
 (** Description of a constructor of a logic sum-type.
     @plugin development guide *)
 and logic_ctor_info =
- { ctor_name: string; (** name of the constructor. *)
+ { mutable ctor_name: string; (** name of the constructor. *)
    ctor_type: logic_type_info; (** type to which the constructor belongs. *)
    ctor_params: logic_type list 
  (** types of the parameters of the constructor. *)
diff --git a/src/plugins/obfuscator/obfuscate.ml b/src/plugins/obfuscator/obfuscate.ml
index 41145d204d60a2076b3f4a98bbb86f85f57c344d..f602d521aaa60e2db91fa4b6058606862d1ecdf8 100644
--- a/src/plugins/obfuscator/obfuscate.ml
+++ b/src/plugins/obfuscator/obfuscate.ml
@@ -161,11 +161,11 @@ class visitor = object
     Cil.DoChildren
 
   method! vlogic_type_info_decl lti =
-    warn "logic type" lti.lt_name;
+    lti.lt_name <- Dictionary.fresh Obfuscator_kind.Logic_type lti.lt_name ;
     Cil.DoChildren
 
   method! vlogic_ctor_info_decl lci =
-    warn "logic constructor" lci.ctor_name;
+    lci.ctor_name <- Dictionary.fresh Obfuscator_kind.Logic_constructor lci.ctor_name ;
     Cil.DoChildren
 
   method! vattr = function
diff --git a/src/plugins/obfuscator/obfuscator_kind.ml b/src/plugins/obfuscator/obfuscator_kind.ml
index f4f1fb22e5b396056789b6d543d1b17e1283e04a..47633a9a28a574c381913a693849d2664462df63 100644
--- a/src/plugins/obfuscator/obfuscator_kind.ml
+++ b/src/plugins/obfuscator/obfuscator_kind.ml
@@ -33,7 +33,9 @@ type k =
   | Logic_var
   | Predicate
   | Type
-      
+  | Logic_type
+  | Logic_constructor
+
 let name_of_kind = function
   | Behavior -> "behavior"
   | Enum -> "enum"
@@ -47,6 +49,8 @@ let name_of_kind = function
   | Logic_var -> "logic variable"
   | Predicate -> "predicate"
   | Type -> "type"
+  | Logic_type -> "logic type"
+  | Logic_constructor -> "logic constructor"
 
 let prefix = function
   | Behavior -> "B"
@@ -61,6 +65,8 @@ let prefix = function
   | Logic_var -> "LV"
   | Predicate -> "P"
   | Type -> "T"
+  | Logic_type -> "LT"
+  | Logic_constructor -> "LC"
 
 include Datatype.Make_with_collections
 (struct
diff --git a/src/plugins/obfuscator/obfuscator_kind.mli b/src/plugins/obfuscator/obfuscator_kind.mli
index 0aa33ec52230294a569a723f00e481c5e67c11e5..25685566b8843a4848c14a17bfd4fb2e0e6bc89c 100644
--- a/src/plugins/obfuscator/obfuscator_kind.mli
+++ b/src/plugins/obfuscator/obfuscator_kind.mli
@@ -33,6 +33,8 @@ type k =
   | Logic_var
   | Predicate
   | Type
+  | Logic_type
+  | Logic_constructor
 
 include Datatype.S_with_collections with type t = k
 val prefix: t -> string