<?php

final class MyValidClass extends SomeOtherClass {
  public function __construct() {
    parent::__construct(null);
  }
}

final class MyInvalidClass {
  public function __construct() {
    parent::__construct(null);
  }

  public function someMethod($x) {
    echo $x::SOME_CONSTANT;
  }
}
~~~~~~~~~~
error:11:5
