Posted by Philip Hallstrom on 05/27/05 22:06

Hi all -
I came across a very odd bug in 4.3.10 (and 4.3.11). It's not in
4.3.4, and it's not in 5.0.4.

My understanding is that in 4.x objects are assigned by value. So, why in
the first part of the code is the output of serialize() indicating a
reference? This would suggest that objects are being copied by
reference.

But in the second when I change $ary[1]->name, the output of the serialize
only changes the second element, not both. Also, changing $obj->name
doesn't have any effect on $ary[0] or $ary[1]. Which would suggest that
$ary[0] and $ary[1] are NOT the SAME thing.

The output below is from 4.3.11. 4.3.4 does not have this problem and the
serialize() output does not indicate any reference.

In 5.0.4, the everything works like I'd expect it to since objects are
assigned by reference.

It's almost like $obj is partially being copied by reference and that
serialize is picking up on that or something...

Should I submit this as a bug? Am I missing something obvious?

Here's the code:

<?php

$obj->name = "Homer";
$ary[] = $obj;
$ary[] = $obj;

$obj1->name = "Homer";
$ary[] = $obj1;

print_r($ary);
print("\n");
print ( serialize($ary) );

print("\n\n---------------------------------------\n\n");

unset($obj); unset($obj1); unset($ary);

$obj->name = "Homer";
$ary[] = $obj;
$ary[] = $obj;

$obj1->name = "Homer";
$ary[] = $obj1;

$ary[1]->name = "Marge";

print_r($ary);
print("\n");
print ( serialize($ary) );

?>

Here's the output:

Array
(
[0] => stdClass Object
(
[name] => Homer
)

[1] => stdClass Object
(
[name] => Homer
)

[2] => stdClass Object
(
[name] => Homer
)

)

a:3:{i:0;O:8:"stdClass":1:{s:4:"name";s:5:"Homer";}i:1;r:2;i:2;O:8:"stdClass":1:{s:4:"name";s:5:"Homer";}}

---------------------------------------

Array
(
[0] => stdClass Object
(
[name] => Homer
)

[1] => stdClass Object
(
[name] => Marge
)

[2] => stdClass Object
(
[name] => Homer
)

)

a:3:{i:0;O:8:"stdClass":1:{s:4:"name";s:5:"Homer";}i:1;O:8:"stdClass":1:{s:4:"name";s:5:"Marge";}i:2;O:8:"stdClass":1:{s:4:"name";s:5:"Homer";}}

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