Well, I solved the problem, which was indeed caused by hardening, though I'm not sure why it only affected this system and not the other. Looking at dmesg I saw "[...] denied RWX mmap of [...]", so all it took to fix it was `paxctl-ng /usr/bin/python3.4m -m`.
Looking at the ebuild for =dev-lang/python-3.4.5, it appears that this mark is set iff libffi is not installed with the pax_kernel useflag – maybe the ebuild should be changed to enable it either way? On Fri, Aug 26, 2016 at 8:14 AM, Deven Lahoti <dey...@mit.edu> wrote: > Attaching the build log, as requested.