class a
    {
    }

    class b
    {
        protected function __construct($x)
        {
        }
    }

    class c extends b
    {
        protected function __construct(a $x)
        {
            $this->t($x);
        }
    }




//

    class a
    {
    }

    class b
    {
        static function t($x)
        {
            return new self($x);
        }
    }

    class c extends b
    {
        static function t(a $x)  // Declaration of c::t() should be compatible with b::t($x)
        {
            return new self($x);
        }
    }


//


    class a
    {
    }

    class b
    {
        protected function __construct($x)
        {
        }
    }

    class c extends b
    {
        public function __construct(a $x)
        {
        }
    }


//


    class a
    {
    }

    class b
    {
        protected static function t($x)
        {
            return new self($x);
        }
    }

    class c extends b
    {
        public static function t($x)
        {
            return new self($x);
        }
    }