terribly sorry, I don't have much information to go off on this other than the build logs from deadsnakes.

I retried this build twice and it seems it consistently fails in this position:

https://launchpadlibrarian.net/537139233/buildlog_ubuntu-bionic-armhf.python3.10_3.10.0~b1-1+bionic2_BUILDING.txt.gz

The relevant logs from the build:

```
./python -m test --pgo --timeout=1200 || true
0:00:00 load avg: 2.37 Run tests sequentially (timeout: 20 min)
0:00:00 load avg: 2.37 [ 1/44] test_array
0:00:11 load avg: 2.23 [ 2/44] test_base64
0:00:15 load avg: 2.13 [ 3/44] test_binascii
0:00:16 load avg: 2.13 [ 4/44] test_binop
0:00:17 load avg: 2.13 [ 5/44] test_bisect
0:00:18 load avg: 2.13 [ 6/44] test_bytes
0:01:18 load avg: 1.41 [ 7/44] test_bz2 -- test_bytes passed in 1 min
0:01:25 load avg: 1.35 [ 8/44] test_cmath
0:01:28 load avg: 1.35 [ 9/44] test_codecs
0:01:52 load avg: 1.23 [10/44] test_collections
0:02:10 load avg: 1.16 [11/44] test_complex
0:02:16 load avg: 1.15 [12/44] test_dataclasses
0:02:23 load avg: 1.14 [13/44] test_datetime
0:03:18 load avg: 1.09 [14/44] test_decimal -- test_datetime passed in 54.9 sec
0:05:06 load avg: 1.01 [15/44] test_difflib -- test_decimal passed in 1 min 47 sec
0:05:24 load avg: 1.01 [16/44] test_embed
0:05:27 load avg: 1.01 [17/44] test_float
0:05:32 load avg: 1.01 [18/44] test_fstring
0:05:43 load avg: 1.00 [19/44] test_functools
0:05:47 load avg: 1.00 [20/44] test_generators
0:05:51 load avg: 1.00 [21/44] test_hashlib
Fatal Python error: Bus error

Current thread 0xf7901220 (most recent call first):
  File "/<<PKGBUILDDIR>>/Lib/test/test_hashlib.py", line 842 in test_gil
  File "/<<PKGBUILDDIR>>/Lib/unittest/case.py", line 549 in _callTestMethod
  File "/<<PKGBUILDDIR>>/Lib/unittest/case.py", line 592 in run
  File "/<<PKGBUILDDIR>>/Lib/unittest/case.py", line 652 in __call__
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 122 in run
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 84 in __call__
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 122 in run
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 84 in __call__
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 122 in run
  File "/<<PKGBUILDDIR>>/Lib/unittest/suite.py", line 84 in __call__
  File "/<<PKGBUILDDIR>>/Lib/test/support/testresult.py", line 169 in run
  File "/<<PKGBUILDDIR>>/Lib/test/support/__init__.py", line 959 in _run_suite
  File "/<<PKGBUILDDIR>>/Lib/test/support/__init__.py", line 1082 in run_unittest
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/runtest.py", line 210 in _test_module
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/runtest.py", line 246 in _runtest_inner2
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/runtest.py", line 282 in _runtest_inner
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/runtest.py", line 154 in _runtest
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/runtest.py", line 194 in runtest
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/main.py", line 423 in run_tests_sequential
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/main.py", line 521 in run_tests
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/main.py", line 694 in _main
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/main.py", line 641 in main
  File "/<<PKGBUILDDIR>>/Lib/test/libregrtest/main.py", line 719 in main
  File "/<<PKGBUILDDIR>>/Lib/test/__main__.py", line 2 in <module>
  File "/<<PKGBUILDDIR>>/Lib/runpy.py", line 86 in _run_code
  File "/<<PKGBUILDDIR>>/Lib/runpy.py", line 196 in _run_module_as_main
```

Are you able to get a C stack trace somehow, e.g. from a dump or by login into the build system interactively and running gdb? The Python traceback isn't much helpful.

Have you already tried ./python -X faulthandler -m test ... ?

Could you please also run tests with "./python -m test -j1 ..." in a new job? This executes every test module in a subprocess. I like to see if other tests are segfaulting, too.

I have talked to our Fedora release engineers. They don't see any issues with armv7hl builds of Python 3.10.0b1. All tests are passing. https://koji.fedoraproject.org/koji/taskinfo?taskID=67234161

Ubuntu's armhf and Fedora's armv7hl both have the platform triplet "arm-linux-gnueabihf". Could the issue be caused by GCC version difference or compiler flags? Fedora uses GCC arch flags -march=armv7-a -mfpu=vfpv3-d16 -mtune=generic-armv7-a -mabi=aapcs-linux -mfloat-abi=hard.

Given that this happens in hashlib, could this be related to the OpenSSL version?

That's possible.

I suspect it's related to test_gil itself. Hash providers don't release the GIL for inputs < 2048 bytes. Hashing of small inputs is faster than releasing and re-acquiring the GIL. For inputs >= 2048 hashlib creates a per-object lock and release the GIL while holding the internal lock. The test case verifies that hashlib works correctly for larger inputs that release the GIL.

In Fedora, our build passed on Fedoras 32, 33, 34, 35.

We have:

F32: gcc 10.2.1, openssl 1.1.1k
F33: gcc 10.3.1, openssl 1.1.1k
F34: gcc 11.1.1, openssl 1.1.1k
F35: gcc 11.1.1, openssl 1.1.1k

Let me know how can I help to debug the difference in environment more.

oddly enough, when I add `-X faulthandler` it passes

___

I did some research on the error message and it looks like the ubuntu maintainers have found the same thing and reported it here:

https://bugs.python.org/issue36445

this points at (intentional?) misaligned accesses being a problem on arm

looks like they've provided a patch as well here: https://bugs.python.org/issue36515

Christian, could you look into that patch?

The fix was merged into 3.10 almost 3 weeks ago, https://github.com/python/cpython/commit/3b2a45ff95a68acc8276b37678c98740a232f6d4 . I forgot to close this bug.