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-lang/yasm-1.3.0-r2::gentoo  USE="nls" 1458 KiB
[ebuild  N     ] media-libs/libvpx-1.16.0:0/12::gentoo  USE="highbitdepth -doc -postproc -static-libs -test" 5504 KiB

Total: 2 packages (2 new), Size of downloads: 6961 KiB