1--TEST--
2Don't optimize send opcodes that differ in by-ref behavior
3--FILE--
4<?php
5
6call_user_func('ref', function_exists('strlen'));
7ref(function_exists('strlen'));
8
9function ref(&$x) {
10    var_dump($x);
11}
12
13?>
14--EXPECTF--
15Warning: ref(): Argument #1 ($x) must be passed by reference, value given in %s on line %d
16bool(true)
17
18Notice: Only variables should be passed by reference in %s on line %d
19bool(true)
20