Revert commits 23078689a, 73042b8d1, ce07aff48, f7df8043f, 6ba0cc4bd,
eb16011f4, 68e7e973d, 63ca350ef. We still have a problem here, but
somebody who's actually a Windows developer will need to spend time
on it.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us