Even though there is no use flag if kerberos libraries are installed then the zfs ebuilds will link to these libraries. If Kerberos libraries are not installed then the zfs ebuilds don't complain and happily builds without them. If zfs links to the kerberos libraries then booting a zfs root filesystem will fail when /usr is not included in the same pool since the libraries are installed to /usr/lib64 once the kernel switches root from initramfs the root zfs filesystem is mounted but then it's copy of zfs fails to import /usr because of the missing shared libraries. This could be avoided by setting USE="-kerberos" when the libraries are needed for the system but are unnecessary for zfs otherwise zfs needs to be built with static-libraries or /usr needs to be moved to /. Testing was done with sys-fs/zfs-0.7.5 The libraries are present in the initramfs it's not failing until we've mounted tank/GENTOO
there's no such knob for zfs and at least modern versions do no link to kerberos libs. I'll close this one.
