Issues

• Python 3.14.7 and later causes PAGE GUI Designer to freeze in startup

  type-bug
  python/cpython#159626 · Filter by author gregwa1953 opened on Oct 17, 2026

• email: IndexError when folding address headers containing empty comments

  stdlibtopic-emailtype-bug
  python/cpython#159621 · Filter by author KohakuBlueleaf opened on Oct 17, 2026

• Remote asyncio stack traces stop at async generators

  stdlibtopic-asynciotype-bug
  python/cpython#159620 · Filter by author deadlovelll opened on Oct 17, 2026

• _pyrepl: IndexError in max_column when recalling a very long single-line history entry

  stdlibtopic-repltype-bug
  python/cpython#159617 · Filter by author nsyhykui opened on Oct 17, 2026

• GitHub Action: "Tail calling interpreter" times out after 60 minutes on macOS x86_64 on building LLVM from source

  infraOS-mac
  python/cpython#159612 · Filter by author vstinner opened on Oct 17, 2026
  2

• test_largefile hangs on x86-64 MacOS Intel ASAN NoGIL buildbot

  OS-macteststype-bug
  python/cpython#159608 · Filter by author vstinner opened on Oct 17, 2026
  2

• test_faulthandler fails randomly on x86-64 MacOS Intel ASAN NoGIL 3.x

  OS-macteststype-bug
  python/cpython#159606 · Filter by author vstinner opened on Oct 17, 2026
  3

• Implement stack size detection on FreeBSD

  interpreter-coreOS-freebsdtype-feature
  python/cpython#159603 · Filter by author vstinner opened on Oct 17, 2026

• imaplib.Idler raises IndexError when another command's tagged response arrives during IDLE

  stdlibtype-bug
  python/cpython#159583 · Filter by author MrGreyfun opened on Oct 16, 2026
  1

• Improve performance of isinstance() for misses and improve documentation

  interpreter-coreperformancetype-feature
  python/cpython#159580 · Filter by author eendebakpt opened on Oct 16, 2026

• test_curses failures on Python 3.16.0a1 with ncurses 6.6 on openSUSE

  buildextension-modulesOS-linuxtopic-cursestype-bug
  python/cpython#159579 · Filter by author mcepl opened on Oct 16, 2026
  1

  

• Avoid the weakref list lock when dereferencing weakrefs

  interpreter-coreperformancetopic-free-threadingtype-feature
  python/cpython#159564 · Filter by author nascheme opened on Oct 16, 2026

• useless AF_VSOCK setsockopt validation code

  extension-modulestopic-sockettype-bug
  python/cpython#159561 · Filter by author benjaminp opened on Oct 16, 2026

• Add a command-line interface to tracemalloc

  stdlibtype-feature
  python/cpython#159560 · Filter by author vadim-smal opened on Oct 16, 2026

• Tracking un-needed nested locks

  extension-modulesinterpreter-coreperformancetype-feature
  python/cpython#159558 · Filter by author johng opened on Oct 16, 2026

• sysconfig.get_platform() on FreeBSD should not include patch level

  OS-freebsdstdlibtype-bug
  python/cpython#159550 · Filter by author mohd-akram opened on Oct 16, 2026
  3

• test_lazy_import.test_deeply_dotted_name() does crash on Alpine Linux (SIGSEGV) and FreeBSD (SIGILL)

  teststopic-lazy-importstype-bug
  python/cpython#159535 · Filter by author vstinner opened on Oct 16, 2026
  6

• test_profiling.test_sampling_profiler: test_is_python_process_non_python_subprocess() failed on AMD64 Alpine Linux NoGIL PR

  teststopic-profilingtype-bug
  python/cpython#159534 · Filter by author vstinner opened on Oct 16, 2026
  1

• Windows ARM64 tail-call interpreter: compiler and commit performance effects

  interpreter-coreOS-windowsperformance
  python/cpython#159521 · Filter by author diegorusso opened on Oct 16, 2026
  1

• On macOS with Python 3.15, test_idle and test_tkinter fail with _tkinter.TclError: invalid command name "::tk::unsupported::MacWindowStyle" on Tk/Tcl 9.1

  OS-macteststopic-tkintertype-bug
  python/cpython#159517 · Filter by author vstinner opened on Oct 16, 2026
  3

• _testcapi._tuple_resize() leaks item references on allocation failure

  3.143.153.16interpreter-coretype-bug
  python/cpython#159514 · Filter by author lagergren-oai opened on Oct 16, 2026
  4

• pystats asserts on valid register-cached uop IDs

  interpreter-coretopic-JITtype-bug
  python/cpython#159511 · Filter by author cocolato opened on Oct 16, 2026

• asyncio: large bytes write is quadratic when queued behind pending data

  performancestdlibtopic-asynciotype-bug
  python/cpython#159503 · Filter by author Ar-maan05 opened on Oct 16, 2026

• Improve performance of asyncio StreamReader .readline() and .readuntil()

  performancestdlibtopic-asynciotype-feature
  python/cpython#159500 · Filter by author cmaloney opened on Oct 16, 2026

• PowerShell venv activation treats square brackets in paths as wildcards

  OS-windowsstdlibtopic-venvtype-bug
  python/cpython#159498 · Filter by author repzakske opened on Oct 15, 2026