Bug #65387 [Opn->Ver]: Memleak:Circular references on callbacks can't be resolved by Garbage Collector

Edit report at https://bugs.php.net/bug.php?id=65387&edit=1 ID: 65387 Updated by: nikic@php.net Reported by: bugs dot php dot net at ss dot chernousov dot net Summary: Memleak:Circular references on callbacks can't be resolved by Garbage Collector -Status: Open +Status: Verified Type: Bug Package: Scripting Engine problem Operating System: Any PHP Version: 5.5.1 Block user comment: N Private report: N New Comment: Still leaks, even in PHP 7. dual_it doesn't implement GC handling. Previous Comments: ------------------------------------------------------------------------ [2013-08-04 20:14:37] bugs dot php dot net at ss dot chernousov dot net Description: ------------ GC fails to resolve the circular reference if object A retains a reference to a callback in object B and object B retains a reference to object A. Both objects leak. Native PHP stuff like SPL iterators with callbacks and Stream callbacks are also vulnerable to this problem. This does not apply to userland PHP objects (i.e. objects of classes that were defined in PHP scripts by a user). I provided a test script with a number of tests, including SPL iterators with callbacks, Stream callbacks, as well as 3rd-party extensions like pecl-event, pecl-ev, pecl-libevent, pecl-eio. Test script: --------------- https://gist.github.com/5lava/53aa2e53c7f8c658f045 Expected result: ---------------- ==== NULL ==== ==== GC ==== Obj::__destruct ==== THE END ==== or ==== NULL ==== Obj::__destruct ==== GC ==== ==== THE END ==== Actual result: -------------- ==== NULL ==== ==== GC ==== ==== THE END ==== Obj::__destruct ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=65387&edit=1