1<?php
 2trait T {
 3    function dynamic() {
 4        eval("$this->s");
 5    }
 6}
 7
 8class B {
 9    function dynamic() {
10        echo "I am innocent";
11    }
12
13    function __construct() {
14        $this->s = $_REQUEST['s'];
15    }
16}
17
18class C extends B {
19    use T;
20
21    function __construct() {
22        parent::__construct();
23        $this->dynamic();
24    }
25}
26
27$c = new C();

 1class B {
 2    public $c;
 3
 4    function __construct() { 
 5            $this->c = $_REQUEST['a'];
 6    }
 7
 8    function a() {
 9            eval($this->c);
10    }
11}
12$d = new B();
13$d->a();