I'm trying to upgrade a Drupal site from 6.34 to 7.x using Drush. When I run drush site-upgrade @alias, everything goes well until step 12-a where it ends up throwing this error :

Unknown option: --uninstall.  See `drush help pm-disable` for available options. To suppress this error, add the option --strict=0.

I made some search about this and tried a few things :

• I created a file ~/.drush/my.drushrc.php using the example code given here : http://api.drush.org/api/drush/examples%21example.drushrc.php/6.x I then uncommented line 198 :

$options['strict'] = FALSE;

• In that same drushrc file, I added this line :

$command_specific['pm-disable'] = array('strict' => 0);

This solution was proposed here : https://www.drupal.org/node/2074781

• I then tried defining a drush alias in my .bash_aliases (https://drupal.stackexchange.com/a/128974/39434)

alias drush='drush --strict=0'

Neither of these solutions helped, I always get the same error.

OS: Ubuntu 14.10
Drush : 6.2.0
PHP: 5.5.12-2ubuntu4.1 (cli)