Crash in plumbum module when importing .so linked with gold

I am not sure it is boost.python's fault, since there are a lot of variables in the equation, but please take a look.

I prepared the repro case and gathered some info in this repo: https://github.com/mmatrosov/plumbum-crash-repro

In short, if you `import` an extension library in c++ which uses `boost.python`, compiles with `clang` and links with `gold`, there is a crash in this line https://github.com/tomerfiliba/plumbum/blob/master/plumbum/commands/processes.py#L286 during program shutdown. It does not happen if the extension is not loaded, and I've never experienced this crash even though plumbum is widely used in our scripts.