OpenSUSE's Spectre Mitigation Approach Is One Of The Reasons For Its Slower Performance

[Ansla]

You only get back to Gentoo if you don't mind running some packages' ./configure as root while building it. (ie. "you can't stop the compiler from being called during phases that run as root." - "some phases (such as pkg_setup) still run as root"). But do let me know if you figure out how to avoid that.



To my knowledge, no unpacking/configuring/compiling happens as root on ArchLinux(at least not when using makepkg), only fully-finalized-package installing. Otherwise I'd be choosing Gentoo also!

Only a broken ebuild would run ./configure as root. There are 2 types of phases, those that start with src_ that are ran as unprivilaged user and are meant for the actual build stages and those that start with pkg_ that are ran as root and are meant for making whatever changes are needed to your system (like creating users/groups).
Portage does not prevent an ebuild from running the compiler in the pkg_* phases and I don't think it could do that, but no well written ebuild would do that.