…/opt/cygwin64/bin/cp.exe: error while loading shared libraries: cygattr-1.dll: cannot open shared object file: No such file or directory
I wasn’t able to find a viable fix on the web.
I found a copy of that file in in old installation, and I copied that into the cygwin bin directory – the cygwin64 and the non-64 one – at least for cygwin64 it fails w/o moaning properly, just that it yields exit code 127.