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

Calculating dependencies ... done!
Dependency resolution took 0.98 s (backtrack: 0/20).

[ebuild  N     ] dev-perl/Regexp-RegGrp-2.10.0-r1::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 10 KiB
[ebuild  N     ] dev-perl/CSS-Packer-2.90.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 10 KiB

Total: 2 packages (2 new), Size of downloads: 20 KiB