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

Calculating dependencies ... done!
Dependency resolution took 1.02 s (backtrack: 0/20).

[ebuild  N     ] dev-lang/yasm-1.3.0-r2::gentoo  USE="nls" 1458 KiB
[ebuild  N     ] media-libs/libaom-3.12.1:0/3::gentoo  USE="examples (-big-endian) -debug -doc -test" CPU_FLAGS_X86="avx avx2 mmx sse sse2 sse3 sse4_1 sse4_2 ssse3" 5369 KiB

Total: 2 packages (2 new), Size of downloads: 6826 KiB