Description:
------------
In some cases, PHP doesn't handle the visibility correctly, allowing a private or protected member to be directly accessed via $obj->prop

This seems to happen when a class stores instances of itself and tries to access their properties.

Reproduce code:
---------------
<?php
class bar
{
    private $a;    
    private $children = array();
    
    public function __construct($infiniteDepth)
    {
        $this->a = 'foo';
        if ($infiniteDepth) $this->children[] = new self(false);
    }
    
    public function privateAcces()
    {
        foreach ($this->children as $child) {
            echo $child->a; // here is the bug
        }
    }    
}

$t = new toto(true);
$t->privateAcces();

Expected result:
----------------
fatal error as we access the private 'a' property from a non-$this context

Actual result:
--------------
the property gets read correctly, as if it was public