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

Calculating dependencies ... done!
Dependency resolution took 1.02 s (backtrack: 0/20).

[ebuild  N     ] sci-visualization/gnuplot-5.4.10-r2::gentoo  USE="X cairo gd readline (-aqua) -bitmap -doc -examples -ggi -latex -libcaca -libcerf -lua -regis -wxwidgets" LUA_SINGLE_TARGET="lua5-1 -lua5-3 -lua5-4" 5555 KiB

Total: 1 package (1 new), Size of downloads: 5555 KiB