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

Calculating dependencies ... done!
Dependency resolution took 0.99 s (backtrack: 0/20).

[ebuild  N     ] dev-perl/IPC-Signal-1.0.0-r3::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 3 KiB
[ebuild  N     ] dev-perl/Thread-SigMask-0.4.0-r1::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 12 KiB
[ebuild  N     ] dev-perl/Signal-Mask-0.8.0-r1::gentoo  USE="-minimal -test" PERL_FEATURES="ithreads (-debug) -quadmath" 12 KiB

Total: 3 packages (3 new), Size of downloads: 26 KiB