--TEST--
Bug #21732 (preg_replace() segfaults with invalid parameters)
--INI--
error_reporting=0
--FILE--
<?php
class foo {
	function cb($param) {
		var_dump($param);
		return "yes!";
	}
}

var_dump(preg_replace('', array(), ''));
var_dump(preg_replace_callback("/(ab)(cd)(e)/", array(new foo(), "cb"), 'abcde'));
?>
--EXPECT--
bool(false)
array(4) {
  [0]=>
  string(5) "abcde"
  [1]=>
  string(2) "ab"
  [2]=>
  string(2) "cd"
  [3]=>
  string(1) "e"
}
string(4) "yes!"