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

Calculating dependencies ... done!
Dependency resolution took 1.04 s (backtrack: 0/20).

[ebuild  N     ] acct-group/nagios-0-r3::gentoo  0 KiB
[ebuild  N     ] acct-user/nagios-0-r3::gentoo  0 KiB
[ebuild  N     ] net-analyzer/nagios-plugins-2.5::gentoo  USE="filecaps ipv6 nls ssh ssl -ldap -mysql -nagios-dns -nagios-game -nagios-ping -postgres -rpc -samba (-selinux) -snmp -suid" 2689 KiB
[ebuild  N     ] net-analyzer/nrpe-4.1.3::gentoo  USE="ssl (-command-args) (-selinux) -tcpd" 515 KiB

Total: 4 packages (4 new), Size of downloads: 3204 KiB