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

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] dev-perl/ExtUtils-Config-0.10.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 14 KiB
[ebuild  N     ] dev-perl/ExtUtils-Helpers-0.28.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 17 KiB
[ebuild  N     ] dev-perl/ExtUtils-Builder-0.20.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 31 KiB
[ebuild  N     ] dev-perl/ExtUtils-Builder-Compiler-0.37.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 30 KiB

Total: 4 packages (4 new), Size of downloads: 90 KiB