diff --git a/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php b/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
index f6c34084ba..00b6f761ae 100644
--- a/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
+++ b/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
@@ -46,7 +46,10 @@ private function getProxyInstantiator()
   }
 
   /**
-   * {@inheritdoc}
+   * A 1to1 copy of parent::shareService.
+   *
+   * @todo https://www.drupal.org/project/drupal/issues/2937010 Since Symfony
+   *   3.4 this is not a 1to1 copy.
    */
   protected function shareService(Definition $definition, $service, $id, array &$inlineServices)
   {
@@ -113,6 +116,9 @@ public function setParameter($name, $value) {
 
   /**
    * A 1to1 copy of parent::callMethod.
+   *
+   * @todo https://www.drupal.org/project/drupal/issues/2937010 Since Symfony
+   *   3.4 this is not a 1to1 copy.
    */
   protected function callMethod($service, $call, array &$inlineServices = array()) {
     $services = self::getServiceConditionals($call[1]);
diff --git a/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php b/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
index e627715637..b74a64fe4f 100644
--- a/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
+++ b/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
@@ -102,7 +102,13 @@ public function testObjectSupportDisabledPecl() {
    * @see \Drupal\Tests\Component\Serialization\YamlTest::testObjectSupportDisabledPecl()
    */
   public function testObjectSupportDisabledSymfony() {
-    $this->setExpectedExceptionRegExp(InvalidDataTypeException::class, '/^Object support when parsing a YAML file has been disabled/');
+    if (method_exists($this, 'setExpectedExceptionRegExp')) {
+      $this->setExpectedExceptionRegExp(InvalidDataTypeException::class, '/^Object support when parsing a YAML file has been disabled/');
+    }
+    else {
+      $this->expectException(InvalidDataTypeException::class);
+      $this->expectExceptionMessageRegExp('/^Object support when parsing a YAML file has been disabled/');
+    }
     $object = new \stdClass();
     $object->foo = 'bar';
     // In core all Yaml encoding is done via Symfony and it does not support