To test endian related code, need to test on both a big-endian machine and little-endian machine.
Unless the host machine is an ARM machine that supports switching endianess, or using build agents of
both types, the best way is to use emulation. For testing, perhaps the easiest emulator to set up
for this task is QEMU.

(Ref: https://create.stephan-brumme.com/big-endian/)

On MacOS:

  brew install qemu

On Ubuntu Linux:

  apt-get install qemu

On RedHat Linux:

  yum install qemu

On Windows:

  download something
  ??

Download the VM image:

  https://create.stephan-brumme.com/big-endian/debian-wheezy-powerpc.qcow2

Run the VM:

 # qemu-system-ppc -hda ./debian-wheezy-powerpc.qcow2 -L bios -m 1G -g 1024x768x8 -net user,hostfwd=tcp::2222-:22 -net nic &
 qemu-system-ppc -hda ./debian-wheezy-powerpc.qcow2 -L bios -m 512M -net user,hostfwd=tcp::2222-:22 -net nic &

Need to set up passwordless login to the VM:

if [ ! -f ~/.ssh/id_rsa.pub ]
then
  ssh-keygen -t rsa -P "your-passphrase"
fi
ssh-copy-id -p2222 root@localhost

Enter password of 'root'. After this, the password won't be needed again.