Description:
------------
Please see code below.
It also crashes in php 7.0.23.

Test script:
---------------
$a = new A();
$a->bar('foo');

class B {};
class A extends B
{
	function bar($func)
	{
		var_dump('foo'); #ok
		var_dump(is_callable('parent::foo')); #ok
		var_dump(is_callable(array('parent', 'foo'))); #crash
	}
	function __call($func, $args)
	{
		//if this function does not exist, it won't crash
	}
};


Expected result:
----------------
string(3) "foo"
bool(false)
bool(false)


Actual result:
--------------
crashed