[Python-Dev] New crash in test_embed on macOS 10.12

[Victor Stinner]

Hi,

2017-12-15 20:55 GMT+01:00 Barry Warsaw <barry at python.org>:
> I haven’t bisected this yet, but with git head, built and tested on macOS 10.12.6 and Xcode 9.2, I’m seeing this crash in test_embed:
>
> ======================================================================
> FAIL: test_bpo20891 (test.test_embed.EmbeddingTests)
> ----------------------------------------------------------------------
> Traceback (most recent call last):
>   File "/Users/barry/projects/python/cpython/Lib/test/test_embed.py", line 207, in test_bpo20891
>     out, err = self.run_embedded_interpreter("bpo20891")
>   File "/Users/barry/projects/python/cpython/Lib/test/test_embed.py", line 59, in run_embedded_interpreter
>     (p.returncode, err))
> AssertionError: -6 != 0 : bad returncode -6, stderr is 'Fatal Python error: PyEval_SaveThread: NULL tstate\n\nCurrent thread 0x00007fffcb58a3c0 (most recent call first):\n'
>
> Seems reproducible across different machines (all running 10.12.6 and Xcode 9.2), even after a make clean and configure.  I don’t see the same failure on Debian, and I don’t see the crashes on the buildbots.
>
> Can anyone verify?

It's a known issue. The hint is in the method name: test_bpo20891 :-)

https://bugs.python.org/issue20891#msg307553

I fixed a bug and added a test for it, but the test showed an unknown
race condition.

I wrote a fix for the race condition, but I was asked to run a
benchmark and I didn't run it yet.

https://github.com/python/cpython/pull/4700

I hesitate to skip the test until I fix the second bug.

Victor