I may go ahead and do a literal clone of your instructions. However, looking at your process, it's what I do, step by step, AFAICT without actually going ahead and doing it.

It's also the fact that it fails in so many different ways. Bazel bombs out after ./configure; the master branch today does not even begin to build at all, the old Bazel workaround is not working anymore. Then there's the gcc issues.

You may have gotten lucky once, who knows why.

Again, do you still have the pip package you claim you've built using this procedure? If so, can you upload it somewhere? I would very much like to test it. Thank you.