diff --git a/infer/src/clang/cFrontend_checkers.ml b/infer/src/clang/cFrontend_checkers.ml
index 152e20487..2232b2607 100644
--- a/infer/src/clang/cFrontend_checkers.ml
+++ b/infer/src/clang/cFrontend_checkers.ml
@@ -330,30 +330,11 @@ let checker_NSNotificationCenter _ decl_info impl_decl_info decls =
            "removeObserver:name:object:") decls in
     exists_method_calling_removeObserver || exists_method_calling_removeObserverName in
 
-  let get_super impl_decl_info =
-    let objc_interface_decl_current =
-      CFrontend_utils.Ast_utils.get_decl_opt_with_decl_ref
-        impl_decl_info.Clang_ast_t.oidi_class_interface in
-    let objc_interface_decl_super =
-      match objc_interface_decl_current with
-      | Some Clang_ast_t.ObjCInterfaceDecl(_, _, _, _, interface_decl_info) ->
-          CFrontend_utils.Ast_utils.get_decl_opt_with_decl_ref interface_decl_info.otdi_super
-      | _ -> None in
-    let objc_implementation_decl_super =
-      match objc_interface_decl_super with
-      | Some ObjCInterfaceDecl(_, _, _, _, interface_decl_info) ->
-          CFrontend_utils.Ast_utils.get_decl_opt_with_decl_ref
-            interface_decl_info.otdi_implementation
-      | _ -> None in
-    match objc_implementation_decl_super with
-    | Some ObjCImplementationDecl(_, _, decl_list, _, impl_decl_info) ->
-        Some (decl_list, impl_decl_info)
-    | _ -> None in
-
   let rec exists_on_hierarchy f super =
     match super with
     | Some (decl_list, impl_decl_info) ->
-        f decl_list || exists_on_hierarchy f (get_super impl_decl_info)
+        (f decl_list
+         || exists_on_hierarchy f (Ast_utils.get_super impl_decl_info))
     | None -> false in
 
   let eventually_removeObserver_in_whole_hierarchy decls impl_decl_info =
diff --git a/infer/src/clang/cFrontend_utils.ml b/infer/src/clang/cFrontend_utils.ml
index 1947710a7..e051d06ad 100644
--- a/infer/src/clang/cFrontend_utils.ml
+++ b/infer/src/clang/cFrontend_utils.ml
@@ -469,6 +469,26 @@ struct
     Buffer.add_string buffer name;
     Buffer.contents buffer
 
+  let get_super impl_decl_info =
+    let objc_interface_decl_current =
+      get_decl_opt_with_decl_ref
+        impl_decl_info.Clang_ast_t.oidi_class_interface in
+    let objc_interface_decl_super =
+      match objc_interface_decl_current with
+      | Some Clang_ast_t.ObjCInterfaceDecl(_, _, _, _, interface_decl_info) ->
+          get_decl_opt_with_decl_ref interface_decl_info.otdi_super
+      | _ -> None in
+    let objc_implementation_decl_super =
+      match objc_interface_decl_super with
+      | Some ObjCInterfaceDecl(_, _, _, _, interface_decl_info) ->
+          get_decl_opt_with_decl_ref
+            interface_decl_info.otdi_implementation
+      | _ -> None in
+    match objc_implementation_decl_super with
+    | Some ObjCImplementationDecl(_, _, decl_list, _, impl_decl_info) ->
+        Some (decl_list, impl_decl_info)
+    | _ -> None
+
 (*
   let rec getter_attribute_opt attributes =
     match attributes with
@@ -486,6 +506,7 @@ struct
         | `Setter setter -> setter.Clang_ast_t.dr_name
         | _ -> (setter_attribute_opt rest)
 *)
+
 end
 
 (* Global counter for anonymous block*)
diff --git a/infer/src/clang/cFrontend_utils.mli b/infer/src/clang/cFrontend_utils.mli
index a532f3605..afb469f59 100644
--- a/infer/src/clang/cFrontend_utils.mli
+++ b/infer/src/clang/cFrontend_utils.mli
@@ -159,6 +159,15 @@ sig
   (* Generates a key for a declaration based on its name and the declaration tag. *)
   val generate_key_decl : Clang_ast_t.decl -> string
 
+  (*
+   * Given an objc impl decl info, return the super class's list of decls and
+   * its objc impl decl info.
+   *)
+  val get_super :
+    Clang_ast_t.obj_c_implementation_decl_info ->
+    (Clang_ast_t.decl list *
+     Clang_ast_t.obj_c_implementation_decl_info)
+      option
 
 end