diff --git a/infer/src/backend/sil.ml b/infer/src/backend/sil.ml
index b3bd22624..6b46dfa31 100644
--- a/infer/src/backend/sil.ml
+++ b/infer/src/backend/sil.ml
@@ -3820,7 +3820,9 @@ let tenv_lookup tenv name =
 
 (** Add a (name,type) pair to the global type environment. *)
 let tenv_add tenv name typ =
-  TypenameHash.replace tenv name typ
+  match typ with
+  | Tvar _ -> assert false
+  | _ -> TypenameHash.replace tenv name typ
 
 (** expand a type if it is a typename by looking it up in the type environment *)
 let rec expand_type tenv typ =
diff --git a/infer/src/clang/cTypes_decl.ml b/infer/src/clang/cTypes_decl.ml
index 4f3e0a278..e8dd9d737 100644
--- a/infer/src/clang/cTypes_decl.ml
+++ b/infer/src/clang/cTypes_decl.ml
@@ -16,8 +16,7 @@ module L = Logging
 exception Typename_not_found
 
 let add_predefined_objc_types tenv =
-  let objc_class_mangled = Mangled.from_string CFrontend_config.objc_class in
-  let objc_class_name = Typename.TN_csu (Csu.Class Csu.Objc, objc_class_mangled) in
+  let class_typename = CType_to_sil_type.get_builtin_objc_typename `ObjCClass in
   let objc_class_type_info =
     Sil.Tstruct {
       Sil.instance_fields = [];
@@ -28,15 +27,8 @@ let add_predefined_objc_types tenv =
       def_methods = [];
       struct_annotations = [];
     } in
-  Sil.tenv_add tenv objc_class_name objc_class_type_info;
-  let class_typename = CType_to_sil_type.get_builtin_objc_typename `ObjCClass in
-  let class_typ = Sil.Tvar (Typename.TN_csu (Csu.Struct, objc_class_mangled)) in
-  Sil.tenv_add tenv class_typename class_typ;
-  let typename_objc_object =
-    Typename.TN_csu (Csu.Struct, Mangled.from_string CFrontend_config.objc_object) in
-  let id_typedef = Sil.Tvar (typename_objc_object) in
+  Sil.tenv_add tenv class_typename objc_class_type_info;
   let id_typename = CType_to_sil_type.get_builtin_objc_typename `ObjCId in
-  Sil.tenv_add tenv id_typename id_typedef;
   let objc_object_type_info =
     Sil.Tstruct {
       Sil.instance_fields = [];
@@ -47,7 +39,7 @@ let add_predefined_objc_types tenv =
       def_methods = [];
       struct_annotations = [];
     } in
-  Sil.tenv_add tenv typename_objc_object objc_object_type_info
+  Sil.tenv_add tenv id_typename objc_object_type_info
 
 (* Whenever new type are added manually to the translation in ast_expressions, *)
 (* they should be added here too!! *)