[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Torben Paetz : -- nosy: +tpaetz ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Daniel Romberg added the comment: I think this issue needs to be reopened. The problem has not been solved completely. We experience a lot fewer crashes in weakref than before this fix, however, there are recursive situations in which copy() is invoked while iterating the

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Antoine Pitrou added the comment: New changeset 48769a28ad6ef4183508951fa6a378531ace26a4 by Antoine Pitrou (Miss Islington (bot)) in branch '3.7': bpo-35615: Fix crashes when copying a Weak{Key,Value}Dictionary. (GH-11384) (GH-11785)

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by miss-islington : -- pull_requests: +11773, 11774, 11775 ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Antoine Pitrou added the comment: New changeset 96d37dbcd23e65a7a57819aeced9034296ef747e by Antoine Pitrou (Fish) in branch 'master': bpo-35615: Fix crashes when copying a Weak{Key,Value}Dictionary. (GH-11384) https://github.com/python/cpython/commit/96d37dbcd23e65a7a57819aeced9034296ef747e

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by miss-islington : -- pull_requests: +11773, 11774 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by miss-islington : -- pull_requests: +11773 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Serhiy Storchaka : -- nosy: +fdrake, pitrou, serhiy.storchaka ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Fish Wang added the comment: Just checked weakref.py on different branches, I think this bug exists in Python 2.7, 3.4, 3.5, and 3.6 as well. -- ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Emmanuel Arias : -- versions: +Python 3.8 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Fish Wang added the comment: Just submitted a PR against the master branch on GitHub. > This can be apply to 3.8? I think so. -- ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Roundup Robot : -- keywords: +patch, patch, patch, patch pull_requests: +10737, 10738, 10739, 10740 stage: -> patch review ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Roundup Robot : -- keywords: +patch, patch pull_requests: +10737, 10738 stage: -> patch review ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Roundup Robot : -- keywords: +patch, patch, patch pull_requests: +10737, 10738, 10739 stage: -> patch review ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Change by Roundup Robot : -- keywords: +patch pull_requests: +10737 stage: -> patch review ___ Python tracker ___ ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Fish Wang added the comment: Thanks for your reply. I'm preparing a PR. However, I'm not sure how to write a reliable test case to trigger the crash outside my application. I will submit the PR for now, and see if anyone on the mailing list has a better idea of what a reliable test case

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Emmanuel Arias added the comment: Hi! Seems like a bug. Please provide a patch. This can be apply to 3.8? -- nosy: +eamanu ___ Python tracker ___

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

Rémi Lapeyre added the comment: Hi, I think this is indeed a bug, `copy()` is expected to succeed. I was able to reproduce the issue in an interpreter but did not succeed to write a test case that triggers the race-condition. I think the fix you suggested is the right solution. --

[issue35615] "RuntimeError: Dictionary changed size during iteration" when copying a WeakValueDictionary

New submission from Fish Wang : I come across this issue recently when developing a multi-threaded PySide2 (Qt) application. When I'm calling .copy() on a WeakValueDictionary, there is a high chance that my application crashes with the following stack backtrace: -- Traceback (most