cython installation stops pycharm debugger

My pycharm debugger does not work and prints as below on debug console.

pydev debugger: process 17904 is connecting

Process finished with exit code -1073741819 (0xC0000005)

detail: I installed cntk in conda environment called cntk-py35. Then I add cntk-py35 environnment as interpreter to pycharm. Pycharm debugger and its breakpoint worked properly until I installed cython as follow

activate cntk-py35 conda install -c anaconda cython

and debugger does not work after this installation BUT cntk-py35 interpreter works in run mode from terminal and pycharm as before.

Can any one tell me what to do? Thank you very much.