What you should do instead is write all your code so it is little-endian only, as the only relevant big-endian architecture is s390x, and if someone wants to run your code on s390x, they can afford a support contract.

I contend it's almost never important and almost nobody writing user software should bother with this. Certainly, people who didn't already know they needed big-endian should not start caring now because they read an article online. There are countless rare machines that your code doesn't run on--what's so special about big endian? The world is little endian now. Big endian chips aren't coming back. You are spending your own time on an effort that will never pay off. If big endian is really needed, IBM will pay you to write the s390x port and they will provide the machine.

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