pytest crashing with ptest-xdist

When running pytest in parallel w/ pytest-xdist, I'm seeing the follow stack trace:

/opt/pyenv/versions/3.10.12/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
<frozen importlib._bootstrap>:1050: in _gcd_import
    ???
<frozen importlib._bootstrap>:1027: in _find_and_load
    ???
<frozen importlib._bootstrap>:1006: in _find_and_load_unlocked
    ???
<frozen importlib._bootstrap>:688: in _load_unlocked
    ???
/usr/local/lib/gravity/poetry/venvs/MXt4Tns3-py3.10/lib/python3.10/site-packages/_pytest/assertion/rewrite.py:174: in exec_module
    co = _read_pyc(fn, pyc, state.trace)
/usr/local/lib/gravity/poetry/venvs/MXt4Tns3-py3.10/lib/python3.10/site-packages/_pytest/assertion/rewrite.py:374: in _read_pyc
    with fp:

E   OSError: [Errno 5] Input/output error

Looking at the code, it seems like we're missing some exception handling.
When I put the entire context in the try/except, everything works as expected.
Seems like this is a best attempt, as if the open fails, we return None.

def _read_pyc(
    source: Path, pyc: Path, trace: Callable[[str], None] = lambda x: None
) -> types.CodeType | None:
    """Possibly read a pytest pyc containing rewritten code.

    Return rewritten code if successful or None if not.
    """
    try:
        fp = open(pyc, "rb")
    except OSError:
        return None
    with fp: <-------------------- shouldn't this be in the try/except?
        try:
            stat_result = os.stat(source)
            mtime = int(stat_result.st_mtime)
            size = stat_result.st_size
            data = fp.read(16)
        except OSError as e:
            trace(f"_read_pyc({source}): OSError {e}")
            return None
        # Check for invalid or out of date pyc file.
        if len(data) != (16):
            trace(f"_read_pyc({source}): invalid pyc (too short)")
            return None
        if data[:4] != importlib.util.MAGIC_NUMBER:
            trace(f"_read_pyc({source}): invalid pyc (bad magic number)")
            return None
        if data[4:8] != b"\x00\x00\x00\x00":
            trace(f"_read_pyc({source}): invalid pyc (unsupported flags)")
            return None
        mtime_data = data[8:12]
        if int.from_bytes(mtime_data, "little") != mtime & 0xFFFFFFFF:
            trace(f"_read_pyc({source}): out of date")
            return None
        size_data = data[12:16]
        if int.from_bytes(size_data, "little") != size & 0xFFFFFFFF:
            trace(f"_read_pyc({source}): invalid pyc (incorrect size)")
            return None
        try:
            co = marshal.load(fp)
        except Exception as e:
            trace(f"_read_pyc({source}): marshal.load error {e}")
            return None
        if not isinstance(co, types.CodeType):
            trace(f"_read_pyc({source}): not a code object")
            return None
        return co

installed python modules:

dev@gvt-dev:~/repo/ws/global-config-manager$ poetry run pip list
Package                   Version
------------------------- -------------
aniso8601                 10.0.1
astroid                   2.15.8
async-timeout             5.0.1
atlassian-python-api      4.0.7
attrs                     25.4.0
backports.asyncio.runner  1.2.0
backports.zstd            1.3.0
beautifulsoup4            4.14.2
blinker                   1.9.0
brotli                    1.2.0
certifi                   2025.11.12
cffi                      2.0.0
cfgv                      3.4.0
charset-normalizer        3.4.4
circus                    0.19.0
click                     8.3.0
confluent-kafka           2.8.0
coverage                  7.11.3
cramjam                   2.11.0
crypto                    1.4.1
cryptography              45.0.7
deepdiff                  8.6.1
Deprecated                1.3.1
dill                      0.4.0
distlib                   0.4.0
enum34                    1.1.10
exceptiongroup            1.3.0
execnet                   2.1.2
fakeredis                 2.32.1
filelock                  3.20.0
flake8                    7.3.0
flake8-tidy-imports       4.12.0
Flask                     3.1.2
Flask-Compress            1.23
flask-restx               1.3.2
gevent                    25.9.1
greenlet                  3.2.4
grpcio                    1.76.0
grpcio-tools              1.71.2
hvac                      2.3.0
icdiff                    2.0.7
identify                  2.6.15
idna                      3.11
importlib_resources       6.5.2
iniconfig                 2.3.0
isort                     5.13.2
itsdangerous              2.2.0
Jinja2                    3.1.6
jmespath                  1.0.1
jsonpickle                4.1.1
jsonschema                4.25.1
jsonschema-specifications 2025.9.1
lazy-object-proxy         1.12.0
libyang                   2.99999.99999
lxml                      6.0.2
MarkupSafe                3.0.3
mccabe                    0.7.0
mmh3                      4.1.0
Naked                     0.1.32
netaddr                   1.3.0
newrelic                  11.2.0
nodeenv                   1.9.1
oauthlib                  3.3.1
orderly-set               5.5.0
packaging                 25.0
pip                       25.1.1
platformdirs              4.5.0
pluggy                    1.6.0
pprintpp                  0.4.0
pre_commit                4.4.0
protobuf                  5.29.5
psutil                    7.1.3
psycopg2-binary           2.9.11
py                        1.11.0
pyang                     2.7.1
pyangbind                 0.8.7
pycodestyle               2.14.0
pycparser                 2.23
pycryptodome              3.23.0
pyflakes                  3.4.0
Pygments                  2.19.2
pylint                    2.17.7
pylint-exit               1.2.0
pyOpenSSL                 25.2.0
pyroaring                 1.0.3
pytest                    8.4.2
pytest-asyncio            1.3.0
pytest-cov                6.3.0
pytest-flask              1.3.0
pytest-forked             1.6.0
pytest-icdiff             0.9
pytest-mock               3.15.1
pytest-sugar              1.1.1
pytest-xdist              3.8.0
python-consul             1.1.0
python-generate-mac       1.3.1
python-snappy             0.7.3
pytz                      2025.2
PyYAML                    6.0.3
pyzmq                     27.1.0
redis                     5.2.1
referencing               0.37.0
regex                     2025.11.3
requests                  2.32.5
requests-mock             1.12.1
requests-oauthlib         2.0.0
retrying                  1.4.2
rpds-py                   0.28.0
setuptools                80.9.0
shellescape               3.8.1
simplekv                  0.14.1
six                       1.17.0
sortedcontainers          2.4.0
soupsieve                 2.8
SQLAlchemy                1.4.54
sqlalchemy-cockroachdb    1.4.4
SQLAlchemy-Utils          0.38.3
termcolor                 3.2.0
tomli                     2.3.0
tomlkit                   0.13.3
tornado                   6.5.2
typing_extensions         4.15.0
urllib3                   2.5.0
uWSGI                     2.0.31
virtualenv                20.35.4
Werkzeug                  3.1.4
wrapt                     1.17.3
zope.event                6.1
zope.interface            8.1

running on mac os, in docker

$ uname -a
Linux gvt-dev 6.10.14-linuxkit #1 SMP Wed Sep 10 06:47:45 UTC 2025 aarch64 aarch64 aarch64 GNU/Linux

• a detailed description of the bug or problem you are having
• output of pip list from the virtual environment you are using
• pytest and operating system versions
• minimal example if possible

Start by reading _pytest/assertion/rewrite.py and the _read_pyc entry point shown in the traceback. Reproduce pytest running in parallel with pytest-xdist, then verify that an OSError during the pyc context handling no longer crashes the run and that the existing fallback behavior remains intact.