I also get these, except the taint.t one which was a problem
with the test and is fixed in 5.8.3. I think all three are related to large file support (which IIRC is new in Cygwin with the 1.5.x series). I've spent a little time looking at them, but not enough to determine if cygwin or perl is at fault.
You are in a maze of twisty little perlio layers, all alike