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-libs/libusb-1.0.27-r1:1::gentoo  USE="-debug -doc -examples -static-libs -test -udev" 629 KiB

Total: 1 package (1 new), Size of downloads: 629 KiB