On one machine I have cygwin version  3.1.7(0.340/5/3), I can copy cygwin
binaries and the corresponding dlls to a folder and then run the cygwin
programs without any problems.

But on another machine I have a newer cygwin,  3.4.7-1.x86_64, and when I
do the same thing, the programs do not work:

e.g.

mkdir /tmp/test
cd /tmp/test
$ ls -1
bash.exe
chroot.exe
cygiconv-2.dll
cygintl-8.dll
cygncursesw-10.dll
cygreadline7.dll
cygwin1.dll

I copied all of bash's required dlls to /tmp/test

When I do a ./bash, it exits immediately on 3.4.7, but on 3.1.7 it works
correctly.

Has something changed in cygwin that prevents this from working?