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-libs/argtable3-3.3.1::gentoo  USE="-examples -test" 174 KiB
[ebuild  N     ] dev-libs/libserialport-0.1.2-r1::gentoo  USE="-static-libs" 460 KiB
[ebuild  N     ] sys-firmware/blisp-0.0.5-r1::gentoo  USE="tools" 167 KiB

Total: 3 packages (3 new), Size of downloads: 800 KiB