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

Calculating dependencies ... done!
Dependency resolution took 0.85 s (backtrack: 1/20).


!!! All ebuilds that could satisfy ">=x11-libs/agg-2.5[X]" have been masked.
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(dependency required by "sci-mathematics/gsl-shell-2.3.5::gentoo" [ebuild])
(dependency required by "=sci-mathematics/gsl-shell-2.3.5" [argument])
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