1--TEST--
2Adding an optional by-ref arg in a child method
3--FILE--
4<?php
5
6class Test1 {
7    public function method1() {
8        $this->method2($x);
9        var_dump($x);
10    }
11    public function method2() {}
12}
13class Test2 extends Test1 {
14    public function method2(&$x = null) {
15        ++$x;
16    }
17}
18(new Test2)->method1();
19
20?>
21--EXPECT--
22int(1)
23