coffnix ~ # emerge -uD world -pv

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

Calculating dependencies... done!
[ebuild     U  ] dev-db/mysql-init-scripts-2.1_alpha4::gentoo [2.0-r1::gentoo] 0 KiB
[ebuild     U  ] x11-misc/xdg-utils-1.1.1::gentoo [1.1.0_rc3_p20150825::gentoo] USE="perl -doc" 289 KiB
[blocks B      ] <sys-apps/openrc-0.16.2 ("<sys-apps/openrc-0.16.2" is blocking dev-db/mysql-init-scripts-2.1_alpha4)

Total: 2 packages (2 upgrades), Size of downloads: 289 KiB
Conflict: 1 block (1 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-apps/openrc-0.12.4-r4:0/0::gentoo, installed) pulled in by
    sys-apps/openrc required by @system
    sys-apps/openrc required by (virtual/baselayout-0:0/0::gentoo, installed)
    >=sys-apps/openrc-0.12.4-r2 required by (sys-apps/kmod-19:0/0::gentoo, installed)
    sys-apps/openrc required by (virtual/service-manager-0:0/0::gentoo, installed)
    sys-apps/openrc required by (sys-apps/baselayout-2.2.0-r6:0/0::gentoo, installed)

  (dev-db/mysql-init-scripts-2.1_alpha4:0/0::gentoo, ebuild scheduled for merge) pulled in by
    dev-db/mysql-init-scripts required by @selected
    dev-db/mysql-init-scripts required by (dev-db/mariadb-10.1.7_rc:0/18::gentoo, installed)


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages