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

Calculating dependencies ... done!
Dependency resolution took 1.10 s (backtrack: 0/20).

[ebuild  N     ] dev-build/corrosion-0.6.1-r1::gentoo  USE="-debug -test" 101 KiB
[ebuild  N     ] app-misc/task-3.4.2::gentoo  USE="-debug -test" 28451 KiB
[ebuild  N     ] dev-lang/tk-8.6.17:0/8.6::gentoo  USE="threads truetype (-aqua) -debug -test -xscreensaver" 4486 KiB
[ebuild  N     ] app-misc/vittk-1.3-r1::gentoo  71 KiB

Total: 4 packages (4 new), Size of downloads: 33108 KiB