diff --git a/lib/Doctrine/DBAL/Migrations/Tools/Console/Command/DiffCommand.php b/lib/Doctrine/DBAL/Migrations/Tools/Console/Command/DiffCommand.php
index <HASH>..<HASH> 100644
--- a/lib/Doctrine/DBAL/Migrations/Tools/Console/Command/DiffCommand.php
+++ b/lib/Doctrine/DBAL/Migrations/Tools/Console/Command/DiffCommand.php
@@ -80,7 +80,7 @@ EOT
         $down = $this->_buildCodeFromSql($configuration, $fromSchema->getMigrateFromSql($toSchema, $platform));
 
         if ( ! $up && ! $down) {
-            $printer->writeln('No changes detected in your mapping information.', 'ERROR');
+            $output->writeln('No changes detected in your mapping information.', 'ERROR');
             return;
         }
 
@@ -101,4 +101,4 @@ EOT
         }
         return implode("\n", $code);
     }
-}
\ No newline at end of file
+}
Fix warnings when generating migrations, due to a bad variable name