You can modify the container here before it is dumped to PHP code.
@api
ContainerBuilder $container:
Overrides CompilerPassInterface::process
public function process(ContainerBuilder $container) {
$classes = array();
foreach ($container
->getExtensions() as $extension) {
if ($extension instanceof Extension) {
$classes = array_merge($classes, $extension
->getClassesToCompile());
}
}
$this->kernel
->setClassCache(array_unique($container
->getParameterBag()
->resolveValue($classes)));
}