Memory leak in eval()'d code

Hi internals, I've tracked down a memory leak to an anonymous class created within eval(): ``` for ($i = 0; $i < 1000000; $i++) { $object = eval('return new class {};'); if ($i % 1000 == 0) { echo memory_get_usage() . "\n"; } } ``` The memory usage quickly ramps up and memory_limit is reached in seconds. Without eval(), the memory usage stays flat. I'm on 7.3.6. *Is this a bug?* Or is this some inherent limitation of eval() that cannot be fixed? Thanks for any insight. Ben *In case you're wondering (I'm sure you are!), I need this to dynamically create an object that implements an arbitrary number of interfaces <https://github.com/brick/schema/blob/master/src/ObjectFactory.php>, for a schema.org <http://schema.org> structured data reader library.*