emerge -upvD world

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

Calculating world dependencies /
!!! All ebuilds that could satisfy ">=app-emulation/emul-linux-x86-medialibs-1.2" have been masked.
!!! One of the following masked packages is required to complete your request:
- app-emulation/emul-linux-x86-medialibs-1.2 (masked by: ~amd64 keyword)

For more information, see MASKED PACKAGES section in the emerge man page or
refer to the Gentoo Handbook.
(dependency required by "media-video/mplayer-bin-1.0_pre8" [ebuild])



!!! Problem resolving dependencies for media-video/mplayer-bin
!!! Depgraph creation failed.