diff --git a/UPGRADE-3.1.md b/UPGRADE-3.1.md
index ca60dcbf81..b9163cfff3 100644
--- a/UPGRADE-3.1.md
+++ b/UPGRADE-3.1.md
@@ -95,9 +95,9 @@ FrameworkBundle
 HttpKernel
 ----------
 
- * Passing objects as URI attributes to the ESI and SSI renderers has been
+ * Passing non-scalar values as URI attributes to the ESI and SSI renderers has been
    deprecated and will be removed in Symfony 4.0. The inline fragment
-   renderer should be used with object attributes.
+   renderer should be used with non-scalar attributes.
 
  * The `ControllerResolver::getArguments()` method has been deprecated and will
    be removed in 4.0. If you have your own `ControllerResolverInterface`
diff --git a/UPGRADE-4.0.md b/UPGRADE-4.0.md
index dbd9c35c44..98e8521520 100644
--- a/UPGRADE-4.0.md
+++ b/UPGRADE-4.0.md
@@ -84,9 +84,9 @@ FrameworkBundle
 HttpKernel
 ----------
 
- * Possibility to pass objects as URI attributes to the ESI and SSI renderers
-   has been removed. The inline fragment renderer should be used with object
-   attributes.
+ * Possibility to pass non-scalar values as URI attributes to the ESI and SSI
+   renderers has been removed. The inline fragment renderer should be used with
+   non-scalar attributes.
 
  * The `ControllerResolver::getArguments()` method has been removed. If you
    have your own `ControllerResolverInterface` implementation, you should
diff --git a/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php b/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
index 8292fa48a1..0d4d26b676 100644
--- a/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
+++ b/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
@@ -65,7 +65,7 @@ abstract class AbstractSurrogateFragmentRenderer extends RoutableFragmentRendere
     {
         if (!$this->surrogate || !$this->surrogate->hasSurrogateCapability($request)) {
             if ($uri instanceof ControllerReference && $this->containsNonScalars($uri->attributes)) {
-                @trigger_error('Passing objects as part of URI attributes to the ESI and SSI rendering strategies is deprecated since version 3.1, and will be removed in 4.0. Use a different rendering strategy or pass scalar values.', E_USER_DEPRECATED);
+                @trigger_error('Passing non-scalar values as part of URI attributes to the ESI and SSI rendering strategies is deprecated since version 3.1, and will be removed in 4.0. Use a different rendering strategy or pass scalar values.', E_USER_DEPRECATED);
             }
 
             return $this->inlineStrategy->render($uri, $request, $options);