This outcome was just super. Systemd was bumped to -188 today. Udev is still at -187. Instead of actually listening to upstream[1], which would be easy with a virtual, we're now stuck with one part of the duo being at one version and the other part of the duo another. And when I login to X with this combo, my display is /upside-down/. And I don't know if it's because our hackery on the tarball has left out some vital part, because disabling stuff in the one ebuild (gudev in systemd) and enabling it in the other is going to cause some non-trivial problem, or if it's simply a bug upstream. But that's okay, because gentooers are powerusers and we're supposed to have the time to debug this stuff, right? This is disgusting. Really. Virtuals are simple. This stuff is freaking *hard*. Whoever it was that forced this on systemd in gentoo should have a big *object* stuck in *place* and be forced to *action* as penance for the time I'll have to waste fixing this.
[1] "And what we will certainly not do is compromise the uniform integration into systemd for some cosmetic improvements for non-systemd systems. (Yes, udev on non-systemd systems is in our eyes a dead end, in case you haven't noticed it yet. I am looking forward to the day when we can drop that support entirely.)" http://lists.freedesktop.org/archives/systemd-devel/2012-August/006066.html Meaning: For now, you're allowed to have udev without systemd but mixing-and-matching udev versions and systemd versions will be unsupported and patching udev will probably break systemd at some point. TL;DR: This is a sucky situation you've put all users of udev in.