re: Michael: this issue is about bootstraping Python. If you want to test a patch or test something else, you must restart from a clean copy of the source code. Either use "make distclean", "git clean -fdx", or recreate the source directory (git clone, decompress an archive, etc.). Then restart from scratch: ./configure && make.

Understood: between these two timestamps: Date: 2020-03-11 18:55 and Date: 2020-03-11 21:36 - I was doing just that on 4 different VM's: AIX 5.3, 6.1, 7.1 and 7.2 - just in case there may be anything specific re: AIX versions (the bots run on AIX 7.1 and 7.2). I also switched away from any NFS based builds because test behaves differently when the build area is an NFS area compared to jfs2.

FYI: I have decided to focus on AIX 7.1 and AIX 7.2 - and am only using gcc (I was also testing runs with both xlc and gcc before I started posting).

Further, I like your suggestion to try: subprocess except _bootsubprocess and shall make a PR to that end. Much more clear about what is going on.

What I am going to do bewtween now and my next post is again - clean slate - update master to latest version - on two servers.

On one server I'll apply your suggestion to _aix_platform.py; on the other I'll patch Lib/distutils/util.py and Lib/sysconfig.py to not even call _aix_platform.py. Ideally, there will be a difference that leads to an understanding of the root cause.