gtk3.22 diplodlg.c:popup_add_menu() sets city_list_ptrs to NULL if giver has no cities at all. Regardless, later there's qsort(city_list_ptrs...) call.
Will rewrite that commit message before pushing - while with some qsort() implementation there could be NULL dereference, let's just say that we avoid using NULL for a nonnull parameter.
gtk3.22 diplodlg.c:popup_add_menu() sets city_list_ptrs to NULL if giver has no cities at all. Regardless, later there's qsort(city_list_ptrs...) call.