wordpress custom post type add post_tag
register_post_type('movies',
array(
'labels' => array(
'name' => 'Movies',
'singular_name' => 'Movie',
'menu_name' => 'MOVIES',
'all_items' => 'All Movies',
'add_new' => 'Add A Movie',
'add_new_item' => 'Add New Movie'
),
'public' => true,
'supports' => array(
'title',
'post-formats',
),
'show_in_admin_bar' => true,
'taxonomies' => array('post_tag'), // add this to your configuration
)
);