This issue tracker has been migrated to GitHub, and is currently read-only.
For more information, see the GitHub FAQs in the Python's Developer Guide.

Author vstinner
Recipients lemburg, mark.dickinson, rhettinger, stutzbach, vstinner
Date 2020-11-11.11:34:57
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>

FAIL: test_nextafter (test.test_math.MathTests)
Traceback (most recent call last):
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/", line 1968, in test_nextafter
    self.assertIsNaN(math.nextafter(NAN, 1.0))
  File "/home/aixtools/buildarea/3.9.aixtools-aix-power6/build/Lib/test/", line 2015, in assertIsNaN"Expected a NaN, got {!r}.".format(value))
AssertionError: Expected a NaN, got 1.0.

The test:

        # NaN
        self.assertIsNaN(math.nextafter(NAN, 1.0))   # <=== HERE
        self.assertIsNaN(math.nextafter(1.0, NAN))
        self.assertIsNaN(math.nextafter(NAN, NAN))

The Linux manual page says: "If x or y is a NaN, a NaN is returned."

But it seems like the AIX libc doesn't implement this rule. Should we implement this rule in Python on AIX?

The strange thing is that it worked previously. test.python of build 338:

platform.platform: AIX-2-00F9C1964C00-powerpc-32bit
sysconfig[HOST_GNU_TYPE]: powerpc-ibm-aix7.2.4.0
platform.architecture: 32bit

The latest green build is built 347. test.pythoninfo of build 347:

platform.architecture: 32bit
platform.platform: AIX-2-00F9C1964C00-powerpc-32bit
sysconfig[HOST_GNU_TYPE]: powerpc-ibm-aix7.2.0.0

Was the machine updated two days ago (2020-11-09), between build 338 and build 347?
Date User Action Args
2020-11-11 11:34:58vstinnersetrecipients: + vstinner, lemburg, rhettinger, mark.dickinson, stutzbach
2020-11-11 11:34:58vstinnersetmessageid: <>
2020-11-11 11:34:57vstinnerlinkissue42323 messages
2020-11-11 11:34:57vstinnercreate