diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
index cf789426e3..3c3276188a 100644
--- a/src/Symfony/Component/HttpKernel/Kernel.php
+++ b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -754,7 +754,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
             $fs->dumpFile($dir.$file, $code);
             @chmod($dir.$file, 0666 & ~umask());
         }
-        $legacyFile = \dirname($dir.$file).'.legacy';
+        $legacyFile = \dirname($dir.key($content)).'.legacy';
         if (file_exists($legacyFile)) {
             @unlink($legacyFile);
         }