https://github.com/gentoo/gentoo/blob/master/sys-libs/glibc/glibc-2.34-r2.ebuild#L643
Would you see something like this on more ebuilds, postgres, mysql, elasticsearch, or have proper FEATURE flag for it instead?
It's all cool and giggles until you realize that even such random variable is not even prefixed with PORTAGE_ or anything, meaning it could be taken out of shell and meant for entirely different thing.
-- Piotr.
