Instead of copying the Portage configuration files to `/etc/portage` and
`/usr/${target}/etc/portage`, the build scripts now use the
configuration directories from the source directory. This avoids issues
with changes (especially removal of files) getting propagated to the
actual configuration paths.
Several packages end up with circular dependencies, depending on which
Portage profile is selected. The default profiles have a circular
dependency between *sys-libs/pam* and *sys-libs/libcap*. Systemd and
SELinux profiles have even more issues.
We can break the circular dependencies by explicitly building *libcap*
with`USE=-pam` first, which happens to be the default configuration
generated by `crossdev`. Then, we need to switch to a more complete
profile in order to build *glibc* and *util-linux*. At this point, the
build root should be complete enough to build anything without circular
dependencies.
Building the OS is now as simple as running `make` on a Gentoo system.
Interestingly, when `make` is executed as a (grand)child process of
another `make` process, it always prints an `Entering directory ...`
message. This breaks the `make kernelversion` command, by adding
extraneous text to the output.