diff --git a/src/Symfony/Component/HttpKernel/DependencyInjection/RegisterControllerArgumentLocatorsPass.php b/src/Symfony/Component/HttpKernel/DependencyInjection/RegisterControllerArgumentLocatorsPass.php
index 2b563a74d7..a106866ec0 100644
--- a/src/Symfony/Component/HttpKernel/DependencyInjection/RegisterControllerArgumentLocatorsPass.php
+++ b/src/Symfony/Component/HttpKernel/DependencyInjection/RegisterControllerArgumentLocatorsPass.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\HttpKernel\DependencyInjection;
 
+use Symfony\Component\DependencyInjection\ChildDefinition;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\Compiler\ServiceLocatorTagPass;
 use Symfony\Component\DependencyInjection\ContainerBuilder;