I follow this post to run the code: https://github.com/src-d/wmd-relax/issues/25#issuecomment-366383792 But it always has error: ``` Segmentation fault: 11 ``` ``` (cvan2) cvans-MacBook-Air:wmd-relax cvanzy$ python test.py Segmentation fault: 11 ``` What is this meaning? How can I solve it?