#32745 [Opn->Bgs]: Incorrect reassignemeent of $this error

ID: 32745 Updated by: johannes@php.net Reported By: jason at amp-design dot net -Status: Open +Status: Bogus Bug Type: Zend Engine 2 problem Operating System: CentOS 3 / RHEL 3 PHP Version: 5CVS-2005-04-18 (dev) New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php $b = $this already creates an object-reference to $this. If you do a $b = &$this PHP couldn't detect that $b is the same as $this, that could be overwritten and this would lead to problems with the engine. Previous Comments: ------------------------------------------------------------------------ [2005-04-18 17:45:56] jason at amp-design dot net Description: ------------ An incorrect message about the reassignment of $this occurs in the 5.1.x branches of PHP. The code below doesn't product any errors... <?php class A {} $a = new A; $b = &$a; ?> but the "Reproduce code" produces an error when you are inside class scope, trying to use the & operator to create a reference to $this. Obviously the code $b = $this; does the exact same thing in PHP5, however this is a problem as existing code (especially stuff written for PHP4 and PHP5) will break. This is certainly the case here as this bug arises in functions/imap_mailbox.php on line 25 of squirrel mail. Please note this was tested using the php5-200504121430 build which is a couple of days old now. I'm pretty sure it will remain in the latest snapshot. I have no idea why this comes up with the "reassigment of $this" error. I would have thought this error would happen if the expression was reversed to say $this = &$b. Reproduce code: --------------- <?php class A { public function test() { $b = &$this; } } $a = new A; $a->test(); ?> Expected result: ---------------- No output. $a is created and $b === $a during the scope of A::test() for the given code above. Actual result: -------------- Fatal error: Cannot re-assign $this in /var/www/html/test.php on line 4 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=32745&edit=1