Plymouth support fails with profile 23.0

[tlhonmey]

Building a new system with the 23.0/hardened profile (also tested with just 23.0, although less so.)
Tested with genkernel-4.2.6 and also -9999

I immediately notice that my old, home-brew inclusion of plymouth fails to function. No worries, since genkernel now has the --plymouth option.

--plymouth, makes genkernel crash building the initramfs however. So I hunt around and find gentoo@233e3fc Applying this seems to fix it so the initramfs actually builds.

Unfortunately, on bootup, I find that the attempt to launch plymouthd gets a "not found" error. (Same error as my homebrew scripts.) If I force the system into a rescue shell to go poking around, I find that "which plymouthd" finds /usr/bin/plymouthd just fine, but executing /usr/bin/plymouthd directly generates the same "not found" error. /usr/bin/plymouth also gives the same error.

I tend to suspect this is a missing library, but unpacking the initramfs and examining its contents shows all libraries listed by lddtree for plymouth and plymouthd as being present in the archive.

Attempts to insert ldd and lddtree into the initramfs for debugging purposes end with running them giving the same "not found" error.

Unpacking the initramfs and chrooting into it results in the same "not found" errors as well, so if somebody knows of a ldd equivalent for debugging chroots that might make sorting this out easier.

I can do any further debugging you might need if you give me some idea of what to try. I can also provide remote console access to an affected system with a few hours notice.