emerge -puvDNt world

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

Calculating dependencies... done!
[nomerge       ] media-sound/pavucontrol-3.0::gentoo  USE="nls"
[nomerge       ]  media-sound/pulseaudio-12.2::gentoo  USE="X alsa alsa-plugin asyncns caps dbus equalizer gdbm glib ipv6 orc qt5 ssl tcpd udev webrtc-aec -bluetooth -doc -gconf -gtk -jack -libressl -libsamplerate -lirc -native-headset (-neon) -ofono-headset (-oss) -realtime (-selinux) -sox (-system-wide) -systemd -test -zeroconf" ABI_X86="(64) -32 (-x32)"
[ebuild   R    ]   sys-apps/tcp-wrappers-7.6.22-r1::gentoo  USE="ipv6 -netgroups -static-libs" ABI_X86="(64) -32* (-x32)" 0 KiB

Total: 1 package (1 reinstall), Size of downloads: 0 KiB