colesbury
commented
2 years ago The issue described bpo-7105 (and maybe bpo-7060) still exists due to a race condition in WeakKeyDictionary. This shows up as test failure that looks like:
test test_weakref failed -- Traceback (most recent call last):
File "Lib/test/test_weakref.py", line 1960, in test_threaded_weak_value_dict_deepcopy
self.check_threaded_weak_dict_copy(weakref.WeakValueDictionary, True)
File "Lib/test/test_weakref.py", line 1940, in check_threaded_weak_dict_copy
raise exc[0]
File "Lib/test/test_weakref.py", line 1897, in dict_copy
_ = copy.deepcopy(d)
File "Lib/copy.py", line 153, in deepcopy
y = copier(memo)
File "Lib/weakref.py", line 189, in __deepcopy__
for key, wr in self.data.items():
RuntimeError: dictionary changed size during iterationThe cause is that the check of "self._iterating" and the call to "_atomic_removal" are not performed atomically together. By the time _atomic_removal() is called, an iteration might have already started.
Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.
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GitHub fields: ```python assignee = None closed_at = None created_at =
labels = ['type-bug', 'library', '3.9', '3.10', '3.11']
title = 'Race condition in WeakKeyDictionary/WeakKeyDictionary'
updated_at =
user = 'https://github.com/colesbury'
```
bugs.python.org fields:
```python
activity =
actor = 'colesbury'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation =
creator = 'colesbury'
dependencies = []
files = ['50440']
hgrepos = []
issue_num = 45809
keywords = ['patch']
message_count = 2.0
messages = ['406357', '406358']
nosy_count = 1.0
nosy_names = ['colesbury']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue45809'
versions = ['Python 3.9', 'Python 3.10', 'Python 3.11']
```
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