as per subject. CONFIG_EXPERIMENTAL has been removed from kernel configs starting with 3.9 ; as such the check for this in the aufs3 ebuild causes it to fail during pkg_setup. Removal of this check seems to suffice to allow aufs3 to build as expected: diff -u -B -r1.1 aufs3-3_p20130519.ebuild --- aufs3-3_p20130519.ebuild 20 May 2013 18:23:25 -0000 1.1 +++ aufs3-3_p20130519.ebuild 24 May 2013 18:20:38 -0000 @@ -34,7 +34,8 @@ MODULE_NAMES="aufs(misc:${S})" pkg_setup() { - CONFIG_CHECK+=" ~EXPERIMENTAL !AUFS_FS" +# CONFIG_CHECK+=" ~EXPERIMENTAL !AUFS_FS" + CONFIG_CHECK+=" !AUFS_FS" use inotify && CONFIG_CHECK+=" ~FSNOTIFY" use nfs && CONFIG_CHECK+=" EXPORTFS" use fuse && CONFIG_CHECK+=" ~FUSE_FS" Note, I haven't looked at the kernel patches to see if they explicitly rely on CONFIG_EXPERIMENTAL being set, yet; i don't believe this is an issue though as my aufs.ko module is not spouting any warnings of functions not existing..
Has been fixed a while ago