diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index 2df00f114e7725a6f9277960a68e536eac5fb4a2..908836e9c0ebe697c1f5a1d78a6394690ee5f9c5 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -974,11 +974,9 @@ protected function initializeSettings(Request $request) {
 
     // If the class loader is still the same, possibly upgrade to the APC class
     // loader.
-    // ApcClassLoader does not support APCu without backwards compatibility
-    // enabled.
     if ($class_loader_class == get_class($this->classLoader)
         && Settings::get('class_loader_auto_detect', TRUE)
-        && extension_loaded('apc')) {
+        && function_exists('apcu_fetch')) {
       $prefix = Settings::getApcuPrefix('class_loader', $this->root);
       $apc_loader = new ApcClassLoader($prefix, $this->classLoader);
       $this->classLoader->unregister();