The following test failure happens on Python 3.10.0a6+ when we make regen-frozen with the same Python version we test: ====================================================================== FAIL: test_frozentable (ctypes.test.test_values.PythonValuesTestCase) ---------------------------------------------------------------------- Traceback (most recent call last): File "/home/churchyard/Dokumenty/RedHat/cpython/Lib/ctypes/test/test_values.py", line 87, in test_frozentable self.assertEqual(items, expected, "PyImport_FrozenModules example " AssertionError: Lists differ: [('__hello__', 129), ('__phello__', -129), ('__phello__.spam', 129)] != [('__hello__', 125), ('__phello__', -125), ('__phello__.spam', 125)] First differing element 0: ('__hello__', 129) ('__hello__', 125) - [('__hello__', 129), ('__phello__', -129), ('__phello__.spam', 129)] ? ^ ^ ^ + [('__hello__', 125), ('__phello__', -125), ('__phello__.spam', 125)] ? ^ ^ ^ : PyImport_FrozenModules example in Doc/library/ctypes.rst may be out of date ---------------------------------------------------------------------- Ran 494 tests in 0.466s FAILED (failures=1, skipped=87) Reproducer: 1. Build Python from source: $ ./configure && make -j... 2. Run ctypes tests: $ ./python -m ctypes.test 3. Regenerate frozen: $ PYTHON_FOR_REGEN=./python make regen-frozen 4. Build Python from source again: $ ./configure && make -j... 5. Run ctypes tests: $ ./python -m ctypes.test Actual result: Tests in (2) pass, tests in (5) fail. The difference after (3) is: diff --git a/Python/frozen_hello.h b/Python/frozen_hello.h index 9c566cc81e..d58b726aa8 100644 --- a/Python/frozen_hello.h +++ b/Python/frozen_hello.h @@ -9,5 +9,5 @@ static unsigned char M___hello__[] = { 100,218,5,112,114,105,110,116,169,0,114,2,0, 0,0,114,2,0,0,0,218,4,110,111,110,101, 218,8,60,109,111,100,117,108,101,62,1,0,0, - 0,115,2,0,0,0,4,1, + 0,115,6,0,0,0,4,0,12,1,255,128, }; Expected results: Tests pass, no diff.

When I run `PYTHON_FOR_REGEN=python3.10 make regen-frozen` with Python 3.10.0a5, I get the same diff and the same problem. When I run `PYTHON_FOR_REGEN=python3.9 make regen-frozen` with Python 3.9.2, I get no diff and no problem (similarly with Python 3.8.8).

I believe the line table format got changed but the frozen code didn't get re-generated. If you try to call co_lines() on the __hello__ code, Python crashes. >>> import __hello__ Hello world! >>> co = __hello__.__spec__.loader.get_code('__hello__') >>> co.co_linetable b'\x04\x01' >>> list(co.co_lines()) python: ../Objects/codeobject.c:1185: PyLineTable_NextAddressRange: Assertion `!at_end(range)' failed. My PR re-generates the code and fixes the test. Perhaps I should also add a test to exercise co_lines() on the frozen code object.

 New changeset 87ec26b812e9c4095c017dc60f246eda37b83ab2 by Neil Schemenauer in branch 'master': bpo-43372: Use _freeze_importlib for regen-frozen. (GH-24759) https://github.com/python/cpython/commit/87ec26b812e9c4095c017dc60f246eda37b83ab2 

Thanks for the fixer!

See also bpo-43445 "Add frozen modules to sys.stdlib_module_names".