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

Calculating dependencies ... done!
Dependency resolution took 1.09 s (backtrack: 0/20).

[ebuild  N     ] sys-boot/gnu-efi-4.0.4::gentoo  USE="(-custom-cflags)" 240 KiB
[ebuild  N     ] app-crypt/sbsigntools-0.9.5::gentoo  168 KiB
[ebuild  N     ] dev-perl/File-Slurp-9999.320.0-r1::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 34 KiB
[ebuild  N     ] app-crypt/efitools-1.9.2-r1::gentoo  USE="-static" 114 KiB

Total: 4 packages (4 new), Size of downloads: 555 KiB