--TEST-- bug #71428: Validation type inheritance with = NULL --FILE-- <?php class A { } class B { public function m(A $a = NULL, $n) { echo "B.m";} }; class C extends B { public function m(A $a , $n) { echo "C.m";} }; ?> --EXPECTF-- Warning: Declaration of C::m(A $a, $n) should be compatible with B::m(?A $a, $n) in %sbug71428.3.php on line 4