Report an exception with Symfony without throwing

DefaultController.php

<?php

namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
use Symfony\Component\HttpKernel\HttpKernelInterface;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\Routing\Annotation\Route;

class DefaultController extends AbstractController
{
    /**
     * @Route("/exception", name="exception")
     */
    public function index(
        RequestStack $requestStack,
        HttpKernelInterface $httpKernel,
        EventDispatcherInterface $dispatcher
    ) {
        try {
            throw new \Exception('derp');
        } catch (\Exception $exception) {
            $request = $requestStack->getCurrentRequest();
            $type = $requestStack->getParentRequest()
                ? HttpKernelInterface::SUB_REQUEST
                : HttpKernelInterface::MASTER_REQUEST;

            $event = new GetResponseForExceptionEvent($httpKernel, $request, $type, $exception);
            $dispatcher->dispatch(KernelEvents::EXCEPTION, $event);
        }
    }
}