Description:
------------
Test tests/lang/bug35239.php causes segfault in php-4.4.3
4.4.2 version is also affected
5.1.4 is unaffected

Reproduce code:
---------------
<?php
$a = new stdClass; 
$a->x0 = new stdClass;
$a->x0->y0 = 'a';
$a->x0->y1 =& $a->x0;
$a->x0->y2 =& $a->x0;
$a->x0->y0 = 'b';
var_dump($a);
$a->x0->y1 = "ok\n";
echo $a->x0;
?>


Expected result:
----------------
No segfault

Actual result:
--------------
(gdb) where
#0  0x00002aaaac8b2250 in raise () from /lib64/libc.so.6
#1  0x00002aaaac8b3720 in abort () from /lib64/libc.so.6
#2  0x00002aaaac8e804f in __libc_message () from /lib64/libc.so.6
#3  0x00002aaaac8ede4f in _int_free () from /lib64/libc.so.6
#4  0x00002aaaac8ee38e in free () from /lib64/libc.so.6
#5  0x000000000053b55a in shutdown_memory_manager (silent=0, clean_cache=0) at /usr/src/redhat/BUILD/php-4.4.3/Zend/zend_alloc.c:492
#6  0x0000000000512b62 in php_request_shutdown (dummy=0x0) at /usr/src/redhat/BUILD/php-4.4.3/main/main.c:1010
#7  0x000000000056bf03 in main (argc=46, argv=0x7fff203128f8) at /usr/src/redhat/BUILD/php-4.4.3/sapi/cli/php_cli.c:883