Description:
------------
When running the below script on PHP 7.1.1, a segmentation fault occurs when calling debug_print_backtrace().

There are 2 files below: 1.php and 2.php

To run it, run:

php 1.php

It seems to be related to the method aliasing for the trait for c2::f1 as f2.  If that line is removed, the script runs cleanly.


Test script:
---------------
1.php:

<?php
trait c2
{
	public static function f1()
	{

	}
}

class c1
{
	use c2
	{
		c2::f1 as f2;
	}

	public static function go()
	{
		return require('2.php');
	}
}

c1::go();

=======

2.php:

<?php
debug_print_backtrace();


Expected result:
----------------
#0  require() called at [/tmp/1.php:19]
#1  c1::go() called at [/tmp/1.php:23]


Actual result:
--------------
#0  c1::Segmentation fault