Spice 0.12.6 fails to emerge if dev-python/six has not been emerged - therefore this should be made a dependency.
Confirmed: Traceback (most recent call last): File "/usr/lib64/spice-protocol/spice_codegen.py", line 7, in <module> from python_modules import spice_parser File "/usr/lib64/spice-protocol/python_modules/spice_parser.py", line 1, in <module> import six ImportError: No module named six
In fact the problem is not with app-emulation/spice-0.12.6 but with app-emulation/spice-protocol-0.12.10 (see https://bugs.gentoo.org/show_bug.cgi?id=565984). 'spice' successfully builds after fixing 'spice-protocol'. -RDEPEND="" +RDEPEND="dev-python/six"
commit d2b59c7384255f91d4cc850aaff3b8d65ee39d80 Author: Christian Affolter <christian.affolter@stepping-stone.ch> Date: Mon Nov 16 23:19:00 2015 +0100 app-emulation/spice: Added dev-python/six build dependency Spice requires Six, the Python 2 and 3 compatibility library, otherwise the build will fail with the following error: [...]