root@x260 ~# emerge -DNup @world

These are the packages that would be merged, in order:

Calculating dependencies -

!!! Problem resolving dependencies for x11-drivers/xf86-video-intel from @selected
... done!

!!! The ebuild selected to satisfy "x11-drivers/xf86-video-intel" has unmet requirements.
- x11-drivers/xf86-video-intel-2.99.917_p20170313::gentoo USE="dri dri3 udev -debug -sna -tools -uxa -xvmc" ABI_X86="(64)"

  The following REQUIRED_USE flag constraints are unsatisfied:
    any-of ( sna uxa )

(dependency required by "@selected" [set])
(dependency required by "@world" [argument])
root@x260 ~#