The [[RecentChanges]] page is broken (doesn't show any history at all) when used with an empty svnpath in the ikiwiki.setup file.
Say you have the following configuration:
rcs => "svn",
svnrepo => "ssh+svn://foo.bar.com/wiki",
svnpath => "",
In the above, $svnpath need to be either empty or "/" - both trigger the 'next unless' check in IkiWiki/Rcs/svn.pm:rcs_recentchanges() as shown in the patch below, thus causing all files to be ignored for [[RecentChanges]].
I can not see why this check is needed in the first place, so here's a patch for removing it :)