GC issue wrt. to resource <-> object cycles?

Hi! I've tried to fix <https://bugs.php.net/72793>, and it looks like there's a general GC issue wrt. to resources referencing objects and vice versa. Aren't resource ZVALS put in the root buffer? See <https://3v4l.org/JYIQs>, which demonstrates the issue better than the test script in the bug report. A steady increase of allocated memory can be seen, even though gc_collect_cycles() is called. When uncommenting unset($this->parser);, everything is fine (the GC wouldn't be involved at all in this case). Wrt. to the PHP 5.6 behavior: this appears fine, but actually it's in error, because of <https://github.com/php/php-src/commit/72ec2e8f>. Not increasing the refcount of parser->object might theoretically lead to use-after-free scenarios. -- Christoph M. Becker