Gentoo xorg-server update conflicts

Question

I ran eix-sync and emerge world -uvDp, then I got below message. I am quite confused by this message. It seems it is saying that the lower version of xorg-server is conflicting withe higher version one. Should I force unemerge xorg-server and try update?

x11-base/xorg-server:0

  (x11-base/xorg-server-1.16.0:0/1.16.0::gentoo, ebuild scheduled for merge) conflicts with
    x11-base/xorg-server:0/1.15.99.903= required by (x11-drivers/xf86-input-synaptics-1.7.6:0/0::gentoo, installed)
                        ^^^^^^^^^^^^^^^
    x11-base/xorg-server:0/1.15.99.903= required by (x11-drivers/xf86-input-evdev-2.8.4:0/0::gentoo, installed)
                        ^^^^^^^^^^^^^^^
    x11-base/xorg-server:0/1.15.99.903= required by (x11-drivers/xf86-video-intel-2.99.912-r1:0/0::gentoo, installed)

Answer 1

It is actually saying that the x11-drivers/xf86-* ebuilds need to be remerged. Portage can do this automatically much of the time, but something in the way the x11 ebuilds are set up still manages to confuse Portage, and we get this blocker.

What can get you worked around this is to merge them all at once explicitly:

emerge -vaD1 =xorg-server-1.16.0 xf86-input-synaptics xf86-input-evdev xf86-video-intel

The -v gives you that extra information, the -a gets emerge to ask you before proceeding (because I was missing some keywords, my first attempt actually wanted to downgrade xorg-server instead of upgrade it, so this is important), the -D will follow prereqs to uncover why it wants to downgrade instead of upgrade (for the extra keywording of ebuilds), and -1 says not to bother putting them into the world file (presumably xorg-server already is, the drivers don't need to be). IIRC, I had to add the following:

=x11-libs/libXfont-1.5.0*
=x11-proto/xproto-7.0.26*

to a file in my /etc/portage/package.keywords directory.

Answer 2

It is saying that the drivers that require Xorg will need to be updated before you update Xorg. It seems that the IO drivers don't yet support the changes made in xorg 1.16.

Don't force an unmerge, that broke my Gentoo system pretty badly. I think 1.16 has a more major internal change, or at least the Arch Linux version (systemd based) does.