diff --git a/src/Symfony/Component/Translation/Dumper/YamlFileDumper.php b/src/Symfony/Component/Translation/Dumper/YamlFileDumper.php
index ecf00fa64ba92..db9e4b3645a39 100644
--- a/src/Symfony/Component/Translation/Dumper/YamlFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/YamlFileDumper.php
@@ -25,7 +25,7 @@ class YamlFileDumper extends FileDumper
 {
     private $extension;
 
-    public function __construct(/**string */$extension = 'yml')
+    public function __construct(string $extension = 'yml')
     {
         $this->extension = $extension;
     }