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

Calculating dependencies ... done!
Dependency resolution took 0.99 s (backtrack: 0/20).

[ebuild  N     ] dev-libs/aws-c-common-1.0.3:0/1.0::gentoo  USE="-test" 641 KiB
[ebuild  N     ] dev-libs/s2n-tls-1.7.12:1::gentoo  USE="-test" 4853 KiB
[ebuild  N     ] dev-libs/aws-c-cal-1.0.0:0/1.0::gentoo  USE="-test" 1664 KiB
[ebuild  N     ] dev-libs/aws-c-io-1.1.0:0/1.1::gentoo  USE="-test" 810 KiB

Total: 4 packages (4 new), Size of downloads: 7967 KiB