title: Running pip causes deadlock
body: <p>When I run pip install or only pip from Windows Command Line, I think that it causes deadlock and it's impossible to exit running process by pressing <strong>CTRL + C</strong></p>
  
  <p>When I run it from Git Bash, it gives me errors</p>
  
  <p><code>0 [sig] bash 9796 get_proc_lock: Couldn't acquire sync_proc_subproc for(5,1), last 7, Win32 error 0</code></p>
  
  <p><code>1040 [sig] bash 9796 proc_subproc: couldn't get proc lock. what 5, val 1</code></p>