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

Calculating dependencies... done!

[ebuild     U ] sys-apps/coreutils-6.10-r1 [6.4] USE="acl nls (-selinux) -static -xattr%" 0 kB
[ebuild     U ] sys-apps/portage-2.1.4.4 [2.1.2.2] USE="-build -doc -epydoc (-selinux)" LINGUAS="-pl" 368 kB
*** Portage will stop merging at this point and reload itself,
    then resume the merge.
[ebuild     U ] app-shells/bash-3.2_p33 [3.1_p17] USE="nls -afs -bashlogger -plugins% -vanilla" 2,564 kB
[blocks B     ] <sys-apps/portage-2.1.4_rc1 (is blocking app-shells/bash-3.2_p33)

Total: 3 packages (3 upgrades, 1 block), Size of downloads: 2,931 kB

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

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

http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked