I have the following code:

<?php
class Test {
private $test;
}
var_dump (new Test);
?>

without xdebug I geht the following output:

object(Test)0000011 (1) {
["test:private"]=>
NULL
}

with xdebug enabled, I get:

object(Test)
'' => null

The same for "protected". "public" works correct.