diff --git a/core/lib/Drupal/Core/Routing/RouteBuilder.php b/core/lib/Drupal/Core/Routing/RouteBuilder.php
index 6399f89..5bea0a5 100644
--- a/core/lib/Drupal/Core/Routing/RouteBuilder.php
+++ b/core/lib/Drupal/Core/Routing/RouteBuilder.php
@@ -73,6 +73,13 @@ class RouteBuilder implements RouteBuilderInterface {
   protected $routeCollection;
 
   /**
+   * Flag that indiciates if we are currently rebuilding the routes.
+   *
+   * @var bool
+   */
+  protected $building = FALSE;
+
+  /**
    * Constructs the RouteBuilder using the passed MatcherDumperInterface.
    *
    * @param \Drupal\Core\Routing\MatcherDumperInterface $dumper
@@ -101,6 +108,10 @@ public function __construct(MatcherDumperInterface $dumper, LockBackendInterface
    * {@inheritdoc}
    */
   public function rebuild() {
+    if ($this->building) {
+      throw new \RuntimeException('Recursive router rebuild detected.');
+    }
+
     if (!$this->lock->acquire('router_rebuild')) {
       // Wait for another request that is already doing this work.
       // We choose to block here since otherwise the routes might not be
@@ -109,6 +120,8 @@ public function rebuild() {
       return FALSE;
     }
 
+    $this->building = TRUE;
+
     $collection = new RouteCollection();
     $this->routeCollection = $collection;
     foreach ($this->getRouteDefinitions() as $routes) {
@@ -165,6 +178,7 @@ public function rebuild() {
     $this->state->delete(static::REBUILD_NEEDED);
     $this->lock->release('router_rebuild');
     $this->dispatcher->dispatch(RoutingEvents::FINISHED, new Event());
+    $this->building = FALSE;
 
     $this->routeCollection = NULL;
 
diff --git a/core/lib/Drupal/Core/Routing/RouteProvider.php b/core/lib/Drupal/Core/Routing/RouteProvider.php
index 22b8177..cc0682a 100644
--- a/core/lib/Drupal/Core/Routing/RouteProvider.php
+++ b/core/lib/Drupal/Core/Routing/RouteProvider.php
@@ -172,8 +172,9 @@ public function getRoutesByNames($names) {
       throw new \InvalidArgumentException('You must specify the route names to load');
     }
 
+    $this->routeBuilder->rebuildIfNeeded();
+
     $routes_to_load = array_diff($names, array_keys($this->routes));
-
     if ($routes_to_load) {
       $result = $this->connection->query('SELECT name, route FROM {' . $this->connection->escapeTable($this->tableName) . '} WHERE name IN (:names)', array(':names' => $routes_to_load));
       $routes = $result->fetchAllKeyed();
@@ -258,6 +259,7 @@ public function getCandidateOutlines(array $parts) {
    */
   public function getRoutesByPattern($pattern) {
     $path = RouteCompiler::getPatternOutline($pattern);
+    $this->routeBuilder->rebuildIfNeeded();
 
     return $this->getRoutesByPath($path);
   }
diff --git a/core/modules/config_translation/config_translation.module b/core/modules/config_translation/config_translation.module
index 956861a..29ea6eb 100644
--- a/core/modules/config_translation/config_translation.module
+++ b/core/modules/config_translation/config_translation.module
@@ -109,19 +109,8 @@ function config_translation_config_translation_info(&$info) {
   if (\Drupal::moduleHandler()->moduleExists('field_ui')) {
     // Add fields entity mappers to all fieldable entity types defined.
     foreach ($entity_manager->getDefinitions() as $entity_type_id => $entity_type) {
-      $base_route = NULL;
-      try {
-        $base_route = $route_provider->getRouteByName('field_ui.field_edit_' . $entity_type_id);
-      }
-      catch (RouteNotFoundException $e) {
-        if ($collection = \Drupal::service('router.builder')->getCollectionDuringRebuild()) {
-          $base_route = $collection->get('field_ui.field_edit_' . $entity_type_id);
-        }
-        // Ignore non-existent routes.
-      }
-
       // Make sure entity type has field UI enabled and has a base route.
-      if ($entity_type->get('field_ui_base_route') && !empty($base_route)) {
+      if ($entity_type->get('field_ui_base_route')) {
         $info[$entity_type_id . '_fields'] = array(
           'base_route_name' => 'field_ui.field_edit_' . $entity_type_id,
           'entity_type' => 'field_config',
diff --git a/core/modules/rest/src/Plugin/Derivative/EntityDerivative.php b/core/modules/rest/src/Plugin/Derivative/EntityDerivative.php
index 5b17bc6..9e7d313 100644
--- a/core/modules/rest/src/Plugin/Derivative/EntityDerivative.php
+++ b/core/modules/rest/src/Plugin/Derivative/EntityDerivative.php
@@ -17,6 +17,8 @@
 
 /**
  * Provides a resource plugin definition for every entity type.
+ *
+ * @see \Drupal\rest\Plugin\rest\resource\EntityResource
  */
 class EntityDerivative implements ContainerDeriverInterface {
 
@@ -113,21 +115,20 @@ public function getDerivativeDefinitions($base_plugin_definition) {
             // @todo remove the try/catch as part of
             // http://drupal.org/node/2158571
             try {
-              $route = $this->routeProvider->getRouteByName($route_name);
-              $this->derivatives[$entity_type_id]['uri_paths'][$link_relation] = $route->getPath();
-            }
-            catch (RouteNotFoundException $e) {
               if (($collection = $this->routeBuilder->getCollectionDuringRebuild()) && $route = $collection->get($route_name)) {
-                $this->derivatives[$entity_type_id]['uri_paths'][$link_relation] = $route->getPath();
               }
               else {
-                // If the route does not exist it means we are in a brittle state
-                // of module enabling/disabling, so we simply exclude this entity
-                // type.
-                unset($this->derivatives[$entity_type_id]);
-                // Continue with the next entity type;
-                continue 2;
+                $route = $this->routeProvider->getRouteByName($route_name);
               }
+              $this->derivatives[$entity_type_id]['uri_paths'][$link_relation] = $route->getPath();
+            }
+            catch (RouteNotFoundException $e) {
+              // If the route does not exist it means we are in a brittle state
+              // of module enabling/disabling, so we simply exclude this entity
+              // type.
+              unset($this->derivatives[$entity_type_id]);
+              // Continue with the next entity type;
+              continue 2;
             }
           }
           else {
diff --git a/core/modules/rest/src/Plugin/rest/resource/EntityResource.php b/core/modules/rest/src/Plugin/rest/resource/EntityResource.php
index b565cea..7b3e49e 100644
--- a/core/modules/rest/src/Plugin/rest/resource/EntityResource.php
+++ b/core/modules/rest/src/Plugin/rest/resource/EntityResource.php
@@ -28,6 +28,8 @@
  *     "http://drupal.org/link-relations/create" = "/entity/{entity_type}"
  *   }
  * )
+ *
+ * @see \Drupal\rest\Plugin\Derivative\EntityDerivative
  */
 class EntityResource extends ResourceBase {
 
diff --git a/core/modules/user/user.module b/core/modules/user/user.module
index 82aca31..c838822 100644
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -1395,6 +1395,11 @@ function user_modules_installed($modules) {
   // Assign all available permissions to the administrator role.
   $rid = \Drupal::config('user.settings')->get('admin_role');
   if ($rid) {
+    /** @var \Drupal\Core\Routing\RouteBuilderInterface $route_builder */
+    $route_builder = \Drupal::service('router.builder');
+    // Some permissions call the url generator, so ensure that the routes are
+    // up to date.
+    $route_builder->setRebuildNeeded();
     /** @var \Drupal\user\PermissionHandlerInterface $permission_handler */
     $permission_handler = \Drupal::service('user.permissions');
     $permissions = $permission_handler->getPermissions();