From fed501d7247053ce46a2ba512bf0e4bb4f483be6 Mon Sep 17 00:00:00 2001 From: Sam Gross Date: Thu, 24 Oct 2024 18:12:51 -0400 Subject: [PATCH] gh-125245: Fix race condition when importing `collections.abc` (#125415) If multiple threads concurrently imported `collections.abc`, some of the threads might incorrectly see the "shim" `Lib/collections/abc.py` module instead of the correct `Lib/_collections_abc.py` module. This affected both the free threading build and the default GIL-enabled build. --- Lib/collections/__init__.py | 3 +++ Lib/collections/abc.py | 3 --- .../Library/2024-10-11-00-40-13.gh-issue-125245.8vReM-.rst | 2 ++ 3 files changed, 5 insertions(+), 3 deletions(-) delete mode 100644 Lib/collections/abc.py create mode 100644 Misc/NEWS.d/next/Library/2024-10-11-00-40-13.gh-issue-125245.8vReM-.rst diff --git a/Lib/collections/__init__.py b/Lib/collections/__init__.py index b47e728484c..d688141f9b1 100644 --- a/Lib/collections/__init__.py +++ b/Lib/collections/__init__.py @@ -29,6 +29,9 @@ __all__ = [ import _collections_abc import sys as _sys +_sys.modules['collections.abc'] = _collections_abc +abc = _collections_abc + from itertools import chain as _chain from itertools import repeat as _repeat from itertools import starmap as _starmap diff --git a/Lib/collections/abc.py b/Lib/collections/abc.py deleted file mode 100644 index 034ba377a0d..00000000000 --- a/Lib/collections/abc.py +++ /dev/null @@ -1,3 +0,0 @@ -import _collections_abc -import sys -sys.modules[__name__] = _collections_abc diff --git a/Misc/NEWS.d/next/Library/2024-10-11-00-40-13.gh-issue-125245.8vReM-.rst b/Misc/NEWS.d/next/Library/2024-10-11-00-40-13.gh-issue-125245.8vReM-.rst new file mode 100644 index 00000000000..c880efe73d0 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-10-11-00-40-13.gh-issue-125245.8vReM-.rst @@ -0,0 +1,2 @@ +Fix race condition when importing :mod:`collections.abc`, which could +incorrectly return an empty module.