$container = new ContainerBuilder();
$container->register('shared_private', 'stdClass')
    ->setPublic(false);
$container->register('shared_private_dep1', 'stdClass')
    ->setProperty('dep', new Reference('shared_private'));
// container is not compiled
$dumper= new PhpDumper($container);
$dump = $dumper->dump();

class PreCompile extends Container
{
    public function __construct()
    {
        parent::__construct();
        $this->methodMap = array(
            'shared_private' => 'getSharedPrivateService',
            'shared_private_dep1' => 'getSharedPrivateDep1Service',
        );
        $this->privates = array(
            'shared_private' => true,
        );
    }

    protected function getSharedPrivateDep1Service()
    {
        $this->services['shared_private_dep1'] = $instance = new \stdClass();

        $instance->dep = $this->get('shared_private');

        return $instance;
    }

    protected function getSharedPrivateService()
    {
        return $this->services['shared_private'] = new \stdClass();
    }
}