POWER6 AIX 3.9:
https://buildbot.python.org/all/#/builders/330/builds/221

test.pythoninfo:

platform.architecture: 32bit
platform.platform: AIX-2-00F9C1964C00-powerpc-32bit
tkinter.TCL_VERSION: 8.4
tkinter.TK_VERSION: 8.4
tkinter.info_patchlevel: 8.5.9

======================================================================
FAIL: test_expr_bignum (test.test_tcl.TclTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/test_tcl.py", line 441, in test_expr_bignum
    self.assertEqual(result, i)
AssertionError: <bignum object: '9223372036854775808'> != 9223372036854775808

======================================================================
FAIL: test_getint (test.test_tcl.TclTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/test_tcl.py", line 148, in test_getint
    self.assertEqual(tcl.getint(' %d ' % i), i)
AssertionError: -9223372036854775808 != 9223372036854775808

======================================================================
FAIL: test_passing_values (test.test_tcl.TclTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/test_tcl.py", line 475, in test_passing_values
    self.assertEqual(passValue(i), i if self.wantobjects else str(i))
AssertionError: '9223372036854775808' != 9223372036854775808

----------------------------------------------------------------------

Interesting that static version is 8.4, but pathlevel is 8.5.9. It means that Tkinter is built with older version of headers and does not support bignum type, but dynamically linked to newer library which can create bignum objects.

There is a problem with tests. They should be skipped if Tkinter is built with old Tcl headers (it is not easy to do reliable). But there is also a problem with configuration which founds too old headers.

New changeset b02ad2458bc127a7afdeef414fa68c9a7f1f32af by Serhiy Storchaka in branch 'master':
bpo-42749: Fix testing bignum if Tkinter is compiled with Tk 8.4 and dynamic linked with Tk >= 8.5 (GH-23955)
https://github.com/python/cpython/commit/b02ad2458bc127a7afdeef414fa68c9a7f1f32af

New changeset dda12ad63e927e93d71462ad77cc84da55bada9b by Miss Islington (bot) in branch '3.9':
bpo-42749: Fix testing bignum if Tkinter is compiled with Tk 8.4 and dynamic linked with Tk >= 8.5 (GH-23955)
https://github.com/python/cpython/commit/dda12ad63e927e93d71462ad77cc84da55bada9b

New changeset 9d7c5ab6a4ae9d69b39bd16c3195bf6405ddc2d1 by Miss Islington (bot) in branch '3.8':
bpo-42749: Fix testing bignum if Tkinter is compiled with Tk 8.4 and dynamic linked with Tk >= 8.5 (GH-23955) (GH-23962)
https://github.com/python/cpython/commit/9d7c5ab6a4ae9d69b39bd16c3195bf6405ddc2d1

The test should be fixed now, but there is a configuration issue.

> New changeset dda12ad63e927e93d71462ad77cc84da55bada9b by Miss Islington (bot) in branch '3.9':
> bpo-42749: Fix testing bignum if Tkinter is compiled with Tk 8.4 and dynamic linked with Tk >= 8.5 (GH-23955)

test_tcl still fails on POWER6 AIX 3.9:
https://buildbot.python.org/all/#/builders/330/builds/226

======================================================================
FAIL: test_expr_bignum (test.test_tcl.TclTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/test_tcl.py", line 451, in test_expr_bignum
    self.assertRaises(TclError, tcl.call, 'expr', str(2**1000))
AssertionError: TclError not raised by call

New changeset 156b7f7052102ee1633a18e9a136ad8c38f66db0 by Serhiy Storchaka in branch 'master':
bpo-42749: Use dynamic version to test for unsupported bignum in Tk (GH-23966)
https://github.com/python/cpython/commit/156b7f7052102ee1633a18e9a136ad8c38f66db0

New changeset 323cbb5531eb72527d0e3b02f28c1cdc5b7fce92 by Miss Islington (bot) in branch '3.8':
bpo-42749: Use dynamic version to test for unsupported bignum in Tk (GH-23966)
https://github.com/python/cpython/commit/323cbb5531eb72527d0e3b02f28c1cdc5b7fce92

New changeset 7bdb3e08251894b49e7893db1dc4868e2656b342 by Miss Islington (bot) in branch '3.9':
bpo-42749: Use dynamic version to test for unsupported bignum in Tk (GH-23966)
https://github.com/python/cpython/commit/7bdb3e08251894b49e7893db1dc4868e2656b342

test_tcl is passed: https://buildbot.python.org/all/#/builders/330/builds/228 .

I confirm that test_tcl pass again on POWER6 AIX 3.9. Thanks Serhiy for the fix!

I checked the following build: https://buildbot.python.org/all/#/builders/330/builds/229