When PYTHON_TARGETS for net-libs/rb_libtorrent-1.0.10 are set to python3.5 only, the package compiles its python bindings against python 2.7 (/usr/lib64/python3.5/site-packages/libtorrent.cpython-35m-x86_64-linux-gnu.so links to libboost_python-2.7.so.1.63.0) and install those bindings into /usr/lib64/python3.5/site-packages/. The bindings do not work in this case (python -c 'import libtorrent as lt; print(lt.__version__)' shows symbol resolution error). When boost is compiled with only python3.5 in its PYTHON_TARGETS, net-libs/rb_libtorrent creates python bindings for 3.5. $ eselect python list Available Python interpreters, in order of preference: [1] python3.5 [2] python3.4 (fallback) [3] python2.7 (fallback)
I haven't been able to reproduce that issue.
Seems to be OK now.