Something

emerge -uDavN world

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

Calculating world dependencies |
!!! All ebuilds that could satisfy ">=dev-libs/glib-2.14" have been masked.
!!! One of the following masked packages is required to complete your request:
- dev-libs/glib-2.14.1 (masked by: ~x86 keyword)

For more information, see MASKED PACKAGES section in the emerge man page or 
refer to the Gentoo Handbook.
(dependency required by "dev-cpp/glibmm-2.14.0" [ebuild])



!!! Problem resolving dependencies for app-cdr/k3b
!!! Depgraph creation failed.