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

Calculating dependencies ... done!
Dependency resolution took 1.51 s (backtrack: 0/20).

[ebuild     UD ] sys-boot/efibootmgr-17-r1::gentoo [18-r2::gentoo] 41 KiB

Total: 1 package (1 downgrade), Size of downloads: 41 KiB