no unpost_menu when item_count is 0

graph_browser.cpp

@@ -139,6 +139,7 @@ void GraphBrowser::cleanUp()
 
   ITEM** old_items = menu_items(menu_);
   const int old_items_count = item_count(menu_);
+  if (old_items_count > 0)
     assert(unpost_menu(menu_) == E_OK);
   assert(free_menu(menu_) == E_OK);
   for (int i = 0; i < old_items_count; ++i)
@@ -307,8 +308,10 @@ void GraphBrowser::addItems(const std::vector<std::string>& stringVector, bool f
   ITEM** old_items = menu_items(menu_);
   const int old_items_count = item_count(menu_);
 
+  if (old_items_count > 0) {
     const int u = unpost_menu(menu_);
     assert (u == E_OK || first_run && u == E_NOT_POSTED);
+  }
 
   const int number_of_new_items = stringVector.size();
   ITEM** new_items = 0;