Description:
------------
So I wrote some faulty code this morning that tried to do $mysqli_result->fetch_object("SomeAbstractClass"); and it ended up crashing the whole PHP.

I tested this also on PHP 7.0.18 on Ubuntu and it also ended up with a segmentation fault.

Test script:
---------------
<?php
$mysqli = new mysqli("127.0.0.1", "xxx", "xxx", "test");
abstract class test {
    public $a;
}
$mysqli->query("SELECT 1 as a")->fetch_object("test");


Expected result:
----------------
PHP should give me some error instead of just crashing.

Actual result:
--------------
Segmentation fault, the whole PHP crashes.