steps to reproduce: 

virtualenv -p 2 ve2
source ve2/bin/activate
pip install roundup -> process hangs at 100% cpu
wget https://files.pythonhosted.org/packages/80/6d/3ccdd66551bb89b90758add63b8814b516d7471348675aa564aab032341f/roundup-2.1.0.tar.gz 
tar -xzvf roundup-2.1.0.tar.gz 
cd roundup-2.1.0
python setup.py install -> process hangs at 100% cpu

debugging yields that get_path('platlib') contains "lib64" instead of "lib" which is searched for in line 94 of setup.py

attached patch corrects this by using .startswith ("lib") which should be sufficient for all archs ?

regards,
marcus.