The Synaptics driver (x11-misc/synaptics), both versions 12.0 and 12.1, have an RDEPEND of >=x11-base/xfree-4.3.0-r4. Unfortunately, that ebuild was removed, so the dependency breaks. It works fine with xfree-4.3.0-r3. Reproducible: Always Steps to Reproduce: 1. 2. 3.
The ebuild was never there. It's made for 4.3.99, and -r4 whenever it's ready. 4.3.0-r3 already supplies the synaptics driver internally, and the synaptics package overwrites this. That's why it's RDEPEND is like that.
s/it's/its
We'll get this right so people can find the right bug.
*** This bug has been marked as a duplicate of 34201 ***