I'm trying to install Pillow in a virtualenv on cygwin64 (all packages up to date) with python3.
command: pip install Pillow
I have checked all the dependencies, and I've tried the rebaseall solution. I've tried it on two different machines, one with anti-virus and one without.

I end up getting a bunch of errors like this:
0 [main] python3 9732 fork: child -1 - forked process 8204 died unexpectedly, retry 0, exit code 0xC0000005, errno 11
Pillow is the only package I've had issues installing.

I'm wiling to help hunt the problem down. Just need some help heading in the right direction.