Marcus,
I'm sorry but my assumption the linker changes are part of 15.11 was wrong. In fact, we postponed them to just after the release. So, I suggest you give plain 41b9f6b a spin via
git checkout -b give_it_spin 41b9f6b make run/pthread
Hope this helps on Ubuntu 14.04 - I can't test as I'm on 12.04.
Greets