diff --git a/roles/mediawiki/files/fedmsg-emit.php b/roles/mediawiki/files/fedmsg-emit.php
index c62bd3ee7c..846d28e8aa 100644
--- a/roles/mediawiki/files/fedmsg-emit.php
+++ b/roles/mediawiki/files/fedmsg-emit.php
@@ -205,7 +205,7 @@ function article_save(
   &$flags,
   $revision,
   &$status,
-  $baseRevId,
+  $baseRevId=0,
   $undidRevId
 ) {