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

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

[ebuild  N     ] media-libs/libogg-1.3.6::gentoo  USE="-static-libs" 430 KiB
[ebuild  N     ] media-libs/opus-1.6.1::gentoo  USE="-custom-modes -debug -deep-plc -doc -dred -hardened -osce -static-libs -test" CPU_FLAGS_X86="sse" 10228 KiB
[ebuild  N     ] media-libs/libopusenc-0.3::gentoo  USE="-doc" 399 KiB
[ebuild  N     ] media-libs/opusfile-0.12-r1::gentoo  USE="float http -doc -fixed-point -static-libs" 461 KiB
[ebuild  N     ] media-sound/opus-tools-0.2-r1::gentoo  USE="-flac" 447 KiB

Total: 5 packages (5 new), Size of downloads: 11964 KiB