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

Calculating dependencies ... done!
Dependency resolution took 0.82 s (backtrack: 0/20).


!!! All ebuilds that could satisfy "=dev-util/cppunit-9999-r1" have been masked.
!!! One of the following masked packages is required to complete your request:
- dev-util/cppunit-9999-r1::gentoo (masked by: missing keyword)

For more information, see the MASKED PACKAGES section in the emerge
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