Well, duh. There’s also -funroll-loops.

I am not sure what you mean, but in the chrooted environment where you compile for a distinct machine you obviously use configuration options, including compiler flags, appropriate for the target computer, not for the host computer, so "-mtune=native" cannot be used.

My point is that you do not need to setup a binrepo or any other complication like this.

You can install easily Gentoo on a very weak computer, by performing the installation on a typical desktop computer, which may run a different Linux distribution, not necessarily also Gentoo, and then just copying the files.

The Gentoo manual has always included information on how to install Gentoo inside a chrooted environment.

You always have to remember to fun roll the loops, though. :)

https://forums.gentoo.org/viewtopic-t-245041-start-25.html

Never forget -Ofast.