Bug #75629 [Opn->Fbk]: Object property references are replaced by references created in functions
| From: | nikic@php.net | Date: | Tue, 05 Dec 2017 11:04:35 +0000 |
| Subject: | Bug #75629 [Opn->Fbk]: Object property references are replaced by references created in functions | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-212939@lists.php.net to get a copy of this message | ||
Edit report at https://bugs.php.net/bug.php?id=75629&edit=1
ID: 75629
Updated by: nikic@php.net
Reported by: ocramius@php.net
Summary: Object property references are replaced by
references created in functions
-Status: Open
+Status: Feedback
Type: Bug
Package: Scripting Engine problem
Operating System: Linux x64
PHP Version: Irrelevant
Block user comment: N
Private report: N
New Comment:
Try clarify, is the behavior you object to the fact that PHP preserves references while cloning? https://3v4l.org/c4iov
Previous Comments:
------------------------------------------------------------------------
[2017-12-05 09:24:11] ocramius@php.net
Causes https://github.com/Ocramius/ProxyManager/pull/396
(original source of the bug)
------------------------------------------------------------------------
[2017-12-05 09:21:00] ocramius@php.net
Description:
------------
See https://3v4l.org/BNDsu
The PHP engine seems to globally replace references of object properties when new object property
references are created in a by-ref function call.
The problem occurs when defining a by-ref parameter in a function and then calling it with an object
property:
function foo(& $param) {
// keep a non-gc reference to $param here and things will break
}
The attached test case demonstrates the issue by using
clone and an array of
references. The same example works when the references are kept in another object.
Possible causes here are:
* clone is misbehaving
* references are misbehaving overall (YIKES!)
* references created in functions are cached somewhere
Test script:
---------------
--TEST--
Keeping a reference to an object property in an array should not override existing references
?>
--FILE--
<?php
class Container
{
/** @var \stdClass|null */
public $referencedProperty;
public function __clone()
{
$this->referencedProperty = clone $this->referencedProperty;
}
}
$references = [];
$container = new Container();
$loadFieldByReference = function (& $referencedProperty) use (& $references) {
$referencedProperty = new \stdClass();
$references[] = & $referencedProperty;
};
$loadFieldByReference($container->referencedProperty);
$container->referencedProperty->publicProperty = 123;
$clone = clone $container;
$clone->referencedProperty->publicProperty = 234;
echo $container->referencedProperty->publicProperty, "\n";
echo $clone->referencedProperty->publicProperty, "\n";
echo $container->referencedProperty === $clone->referencedProperty ? "same\n" :
"not same\n";
?>
--EXPECT--
123
234
not same
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=75629&edit=1