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

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

[ebuild  N     ] net-libs/paho-mqtt-c-1.3.15:1.3::gentoo  USE="high-performance ssl -doc -examples -test" 1314 KiB

Total: 1 package (1 new), Size of downloads: 1314 KiB