Description:
------------
When trying to access a magically returned (via __get()) property of a class, only an E_NOTICE is raised.  

While a function like array_pop will return a value (without modifying the overloaded property), some other operations will have less predictable results, such as array access via the "[]" syntax.  Because a lot of distributions ship with a "$something | ~E_NOTICE" level of error reporting, and the "black box" ideas of object oriented programming (a developer trying to push an element onto a member array in an API class, for instance), this could be a very hard circumstance to debug.  Furthermore, any case I can think of where this notice will be raised will never perform as expected, it will force the developer to re-engineer his solution.  Because any case where this error would be raised will force a rewrite, I think that this circumstance should raise a fatal error instead.

The fix is trivial enough that I did not attach a patch, but would be glad to in the future, if necessary.

Reproduce code:
---------------
<?php

class foo {
        private $bar = array('1', '2', '3');
        public function __get($var) {
                return $this->$var;
        }
}

$inst = new foo();
var_dump(array_pop($inst->bar));


Expected result:
----------------
PHP Fatal Error:  Indirect modification of overloaded property foo::$bar has no effect in /home/blahblah/test.php on line 10


Actual result:
--------------
PHP Notice:  Indirect modification of overloaded property foo::$bar has no effect in /home/blahblah/test.php on line 10