Issues

• Free-threaded: concurrent syslog.openlog() and sys.argv[0] assignment crash the interpreter

  python/cpython#159864 · opened on Oct 20, 2026
  1

• Free-threading: QSBR thread states false-share on 128-byte cache lines (Apple Silicon), CPU-bound threads reach ~6× on 14 cores where processes reach ~10×

  python/cpython#159860 · opened on Oct 20, 2026
  1

• email: set_content() raises AttributeError for memoryview with 7bit, 8bit or binary CTE

  python/cpython#159858 · opened on Oct 20, 2026

• Shell python3-config prints empty or wrong paths when its installation path contains spaces

  python/cpython#159819 · opened on Oct 20, 2026

• Do not leave stale OpenSSL errors in _hashlib

  python/cpython#159815 · opened on Oct 19, 2026

• _hashlib: GIL may be released while attempting to set an exception

  python/cpython#159811 · opened on Oct 19, 2026

• Struct definitions in the documentation differ from the implementation

  python/cpython#159808 · opened on Oct 19, 2026
  1

• warnings.simplefilter("once") emits the same warning once per module

  python/cpython#159792 · opened on Oct 19, 2026

• HACL* update() errors are handled without a thread state

  python/cpython#159786 · opened on Oct 19, 2026

• Python 3.14 crash randomly on AMD64 Debian root 3.14 buildbot

  python/cpython#159764 · opened on Oct 19, 2026
  11

• Sharing a memoryview iterator across threads can abort free-threaded CPython

  python/cpython#159760 · opened on Oct 19, 2026

• Fix minor safety issues

  python/cpython#159739 · opened on Oct 19, 2026

• pathlib match, full_match and glob take exponential time on short patterns because glob.translate skips fnmatch's atomic-group rewrite

  python/cpython#159717 · opened on Oct 19, 2026
  2

• Speed up integer searching in memoryview and array.array

  python/cpython#159716 · opened on Oct 19, 2026
  2

• ZoneInfo mishandles TZ footer rules spanning a year boundary

  python/cpython#159715 · opened on Oct 19, 2026

• ZoneInfo evaluates TZ rule J59 as February 29 in leap years

  python/cpython#159714 · opened on Oct 19, 2026

• ZoneInfo evaluates zero-based TZ day-of-year rules one day early

  python/cpython#159712 · opened on Oct 19, 2026

• ZoneInfo.utcoffset() gives the wrong offset near the last explicit TZif transition

  python/cpython#159708 · opened on Oct 19, 2026

• Pure-Python ZoneInfo.fromutc() misses folds at the last explicit transition before TZ footer rules

  python/cpython#159707 · opened on Oct 19, 2026

• Pure-Python ZoneInfo.fromutc() misses folds in zones with a single transition

  python/cpython#159706 · opened on Oct 19, 2026
  2

• Speed up float encoding in json

  python/cpython#159702 · opened on Oct 19, 2026
  9

• traceback formatting raises FileNotFoundError with empty sys.path

  python/cpython#159693 · opened on Oct 19, 2026
  3

• TimedRotatingFileHandler stops rolling over permanently once doRollover() exits without updating rolloverAt

  python/cpython#159690 · opened on Oct 19, 2026

• ProcessPoolExecutor: future never completes and interpreter cannot exit when a worker is killed while sending its result

  python/cpython#159689 · opened on Oct 18, 2026

• configparser: ExtendedInterpolation._interpolate_some exceeds common complexity limits

  python/cpython#159686 · opened on Oct 18, 2026