Index: common.php
===================================================================
--- common.php	(revision 788)
+++ common.php	(working copy)
@@ -1882,7 +1882,14 @@
 /** Return the Trac URL */
 function get_trac_diff_url($projecturl, $directory, $file, $revision)
 {
-  $diff_url = $projecturl."/".$directory."/".$file."?rev=".$revision;
+  if ($directory == "")
+    {
+    $diff_url = $projecturl."/".$file."?rev=".$revision;
+    }
+  else
+    {
+    $diff_url = $projecturl."/".$directory."/".$file."?rev=".$revision;
+    }
   return make_cdash_url($diff_url);
 }