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

Calculating dependencies ... done!
Dependency resolution took 0.97 s (backtrack: 0/20).

[ebuild  N     ] dev-libs/rremove-1.0.5::gentoo  USE="-static-libs" 298 KiB
[ebuild  N     ] app-misc/colordiff-1.0.22::gentoo  USE="-verify-sig" 25 KiB
[ebuild  N     ] dev-util/archdiff-1.1.6-r1::gentoo  USE="bzip2 lzma zlib" 95 KiB

Total: 3 packages (3 new), Size of downloads: 417 KiB