Bug Report

Summary

The OPCache wasted memory increases on each request if a paginator is used.

Current behavior

Whenever you make a request on a controller with a Doctrine\ORM\Query that uses Doctrine\ORM\Tools\Pagination\Paginator#getIterator(), the DQL to SQL parser cache is redone each time.
Seems that this is bad a side effect introduced in commit 023e946 which was merged in 2.6.5 so every version between this and 2.12.3 should be impacted.

How to reproduce

1. Install a Symfony app with Doctrine with the following standard cache configuration:

# config/packages/prod/doctrine.yaml
doctrine:
    orm:
        auto_generate_proxy_classes: false
        metadata_cache_driver:
            type: pool
            pool: doctrine.system_cache_pool
        query_cache_driver:
            type: pool
            pool: doctrine.system_cache_pool
        result_cache_driver:
            type: pool
            pool: doctrine.result_cache_pool

framework:
    cache:
        pools:
            doctrine.result_cache_pool:
                adapter: cache.app
            doctrine.system_cache_pool:
                adapter: cache.system

2. Create a controller that uses a Doctrine\ORM\Query with a paginator (i.e. knplabs/knp-paginator-bundle).

3. Set the environment to prod in .env (APP_ENV=prod and APP_DEBUG=0).

4. Make requests on the controller and watch opcache_get_status()['memory_usage']['wasted_memory'] increase each time until OPCache is full and resets itself.

The expireQueryCache flag is always set to true here:

This makes Doctrine reparse the DQL each time:

Then Symfony will recreate the exact same file in its cache in var/cache/prod/pools/, invalidate and recompile it into OPCache:
https://github.com/symfony/cache/blob/7d8415956df68c8dcbc9468e119945e39bacead1/Adapter/PhpFilesAdapter.php#L254-L259

Expected behavior

The OPCache wasted_memory doesn't increase on each request.