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

Calculating dependencies ... done!
Dependency resolution took 1.07 s (backtrack: 0/20).

[ebuild  N     ] dev-libs/libmcrypt-2.5.8-r7::gentoo  1304 KiB
[ebuild  N     ] app-crypt/mhash-0.9.9.9-r4::gentoo  USE="-static-libs" 910 KiB
[ebuild  N     ] app-crypt/mcrypt-2.6.8-r3::gentoo  USE="nls" 461 KiB
[ebuild  N     ] app-backup/hdup-2.0.14-r2::gentoo  USE="crypt" 86 KiB

Total: 4 packages (4 new), Size of downloads: 2761 KiB