Description:
------------
Is there any limit i also tried with memory_get_usage and with 29000 linkedlistnodes it uses about 9.25MB. In php.ini i have max 128MB, so this can't be the problem.

Reproduce code:
---------------
<?php
  class LinkedListNode {
    public $data;
    public $next;

    public function __construct($data) {
      $this->data = $data;
      $this->next = NULL;
    }
  }

  class LinkedList {
    private $first;
    private $last;

    public function __construct() {
      $this->first = NULL;
      $this->last = NULL;
    }

    public function insertLast($data) {
      $node = new LinkedListNode($data);

      if( $this->first != NULL ) {
        $this->last->next = &$node;
        $this->last = &$node;
      }
      else {
        $this->first = &$node;
        $this->last = &$node;
      }
    }
  }

  $list = new LinkedList();

  /* it works
  for($i = 0; $i < 29488; $i++) {
    $list->insertLast(1);
  }*/

  // Segmentation fault
  for($i = 0; $i < 29489; $i++) {
    $list->insertLast(1);
  }
?>

Expected result:
----------------
Nothin, it should exit normally, not segfault.

Actual result:
--------------
 php test2.php
Segmentation fault