ask and edit an extra comment field

The get_comment_ID function was not working.
So use following code in location_meta_call function

function location_meta_call(){
    $location = get_comment_meta($_GET["c"],'location', true);
}

add_filter('comment_save_pre','location_save');

function location_save($comment_content){
    global $wpdb;

    $id = $_POST['comment_ID'];
    $text = $_POST['location_meta_box_text'];

    update_comment_meta($id , 'location', $text);
    return $comment_content;
}