My - bad - this was largely a duplicate of three now closed issues: issue10656, issue16189, and issue25825

as far as the build process goes the issue is fixed. However, issue10656 is not yet "fully-finished" because "make distclean" does not complete successfully. Among other things it leaves Makefile and config.status behind.

Question: re: issue10656 - shall I open a new issue, or reply (reopen) the original?

issue16189 and issue25825 are largely duplicates, as far as I can tell. And unfortunately - "neither" is repaired.

There are three (environment) variables that are used: BLDSHARED (during build - seems fixed), LDSHARED and LDCXXSHARED.

Short summary:
BLDSHARED is fixed per issue10656
LDSHARED is changed (issue16189 and issue25825), but still broken
LDCXXSHARED - was, and is - correct in _sysconfigdata.py

Here is what I have in the 'installed' state:

PATCHED by hand!
root@x064:[/data/prj/python/python-2.7.13]grep LDS /opt/lib/python2.7/_sysconfigdata.py
 'BLDSHARED': './Modules/ld_so_aix xlc_r -bI:./Modules/python.exp -L/opt/lib',
 'LDSHARED': '/opt/lib/python2.7/config/ld_so_aix xlc_r -bI:/opt/lib/python2.7/config/python.exp',

What comes with 2.7.13 by default:
root@x064:[/data/prj/python/python-2.7.13]grep LDS /opt/lib/python2.7/_sysconfigdata.py
 'BLDSHARED': 'Modules/ld_so_aix xlc_r -bI:Modules/python.exp -L/opt/lib',
 'LDSHARED': 'Modules/ld_so_aix xlc_r -bI:Modules/python.exp -L/opt/lib',

This is where ld_so_aix is  'installed':
 /opt/lib/python2.7/config/ld_so_aix         aixtools.python.rte   File

As python does now about where everything else in /opt/lib/pythonX.Y is,
I think this still needs a small change - Modules/* is wrong in any case.

FYI: In both cases this parameter is correct!
 'LDCXXSHARED': '/opt/lib/python2.7/config/ld_so_aix xlc_r -bI:/opt/lib/python2.7/config/python.exp',

Maybe this helps identify what needs fixing!

Moving forward:
a) close this issue - most of it is a duplicate - I will open a new issue for the issue (read my question) re: the cause/importance of all the 'Skipping' (an 'issue' because I see it once, or not at all, and then it goes away)
b) comment on whether I should open a new issue, or comment to the closed issues.