diff --git a/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
index c61acdf065..fa8c636edc 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
@@ -60,11 +60,16 @@ abstract class FileLoader extends BaseFileLoader
         $interfaces = array();
         $singlyImplemented = array();
 
-        foreach ($classes as $class) {
+        foreach ($classes as $class => $errorMessage) {
             if (interface_exists($class, false)) {
                 $interfaces[] = $class;
             } else {
-                $this->setDefinition($class, unserialize($serializedPrototype));
+                $this->setDefinition($class, $definition = unserialize($serializedPrototype));
+                if (null !== $errorMessage) {
+                    $definition->addError($errorMessage);
+
+                    continue;
+                }
                 foreach (class_implements($class, false) as $interface) {
                     $singlyImplemented[$interface] = isset($singlyImplemented[$interface]) ? false : $class;
                 }
@@ -139,13 +144,25 @@ abstract class FileLoader extends BaseFileLoader
             if (!preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $class)) {
                 continue;
             }
+
+            try {
+                $r = $this->container->getReflectionClass($class);
+            } catch (\ReflectionException $e) {
+                $classes[$class] = sprintf(
+                    'While discovering services from namespace "%s", an error was thrown when processing the class "%s": "%s".',
+                    $namespace,
+                    $class,
+                    $e->getMessage()
+                );
+                continue;
+            }
             // check to make sure the expected class exists
-            if (!$r = $this->container->getReflectionClass($class)) {
+            if (!$r) {
                 throw new InvalidArgumentException(sprintf('Expected to find class "%s" in file "%s" while importing services from resource "%s", but it was not found! Check the namespace prefix used with the resource.', $class, $path, $pattern));
             }
 
             if ($r->isInstantiable() || $r->isInterface()) {
-                $classes[] = $class;
+                $classes[$class] = null;
             }
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/Prototype/BadClasses/MissingParent.php b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/Prototype/BadClasses/MissingParent.php
new file mode 100644
index 0000000000..53c97249cf
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/Prototype/BadClasses/MissingParent.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses;
+
+class MissingParent extends MissingClass
+{
+}
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/config/prototype.php b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/config/prototype.php
index 21cab6c6af..622c51af57 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/config/prototype.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/config/prototype.php
@@ -9,7 +9,7 @@ return function (ContainerConfigurator $c) {
         ->tag('baz');
     $di->load(Prototype::class.'\\', '../Prototype')
         ->autoconfigure()
-        ->exclude('../Prototype/{OtherDir}')
+        ->exclude('../Prototype/{OtherDir,BadClasses}')
         ->factory('f')
         ->deprecate('%service_id%')
         ->args(array(0))
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services_prototype.xml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services_prototype.xml
index 333e71ce57..381f95dd00 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services_prototype.xml
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services_prototype.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
   <services>
-      <prototype namespace="Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\" resource="../Prototype/*" exclude="../Prototype/{OtherDir}" />
+      <prototype namespace="Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\" resource="../Prototype/*" exclude="../Prototype/{OtherDir,BadClasses}" />
   </services>
 </container>
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_prototype.yml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_prototype.yml
index fb47bcb7e7..8c0b202aab 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_prototype.yml
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_prototype.yml
@@ -1,4 +1,4 @@
 services:
     Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\:
         resource: ../Prototype
-        exclude: '../Prototype/{OtherDir}'
+        exclude: '../Prototype/{OtherDir,BadClasses}'
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/FileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/FileLoaderTest.php
index 4cba7443e8..8a271a818a 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/FileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/FileLoaderTest.php
@@ -25,6 +25,7 @@ use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
 use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingParent;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\OtherDir\AnotherSub\DeeperBaz;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\OtherDir\Baz;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\Foo;
@@ -163,6 +164,26 @@ class FileLoaderTest extends TestCase
         $this->assertFalse($alias->isPrivate());
     }
 
+    public function testMissingParentClass()
+    {
+        $container = new ContainerBuilder();
+        $container->setParameter('bad_classes_dir', 'BadClasses');
+        $loader = new TestFileLoader($container, new FileLocator(self::$fixturesPath.'/Fixtures'));
+
+        $loader->registerClasses(
+            (new Definition())->setPublic(false),
+            'Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\\',
+            'Prototype/%bad_classes_dir%/*'
+        );
+
+        $this->assertTrue($container->has(MissingParent::class));
+
+        $this->assertSame(
+            array('While discovering services from namespace "Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\", an error was thrown when processing the class "Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingParent": "Class Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingClass not found".'),
+            $container->getDefinition(MissingParent::class)->getErrors()
+        );
+    }
+
     /**
      * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
      * @expectedExceptionMessageRegExp /Expected to find class "Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\Prototype\\Bar" in file ".+" while importing services from resource "Prototype\/Sub\/\*", but it was not found\! Check the namespace prefix used with the resource/