- Update to 3.12.0rc3:
  - Core and Builtins
    - gh-109496: On a Python built in debug mode, Py_DECREF() now
      calls _Py_NegativeRefcount() if the object is a dangling pointer
      to deallocated memory: memory filled with 0xDD “dead byte” by
      the debug hook on memory allocators. The fix is to check the
      reference count before checking for _Py_IsImmortal(). Patch by
      Victor Stinner.
    - gh-109371: Deopted instructions correctly for tool
      initialization and modified the incorrect assertion in
      instrumentation, when a previous tool already sets INSTRUCTION
      events
    - gh-105658: Fix bug where the line trace of an except block
      ending with a conditional includes an excess event with the line
      of the conditional expression.
    - gh-109219: Fix compiling type param scopes that use a name which
      is also free in an inner scope.
    - gh-109341: Fix crash when compiling an invalid AST involving a
      ast.TypeAlias.
    - gh-109195: Fix source location for the LOAD_* instruction
      preceding a LOAD_SUPER_ATTR to load the super global (or
      shadowing variable) so that it encompasses only the name super
      and not the following parentheses.
    - gh-109118: Disallow nested scopes (lambdas, generator
      expressions, and comprehensions) within PEP 695 annotation
      scopes that are nested within classes.
    - gh-109114: Relax the detection of the error message for invalid
      lambdas inside f-strings to not search for arbitrary replacement
      fields to avoid false positives. Patch by Pablo Galindo
    - gh-109118: Fix interpreter crash when a NameError is raised
      inside the type parameters of a generic class.
    - gh-108976: Fix crash that occurs after de-instrumenting a code
      object in a monitoring callback.
    - gh-108732: Make iteration variables of module- and class-scoped
      comprehensions visible to pdb and other tools that use
      frame.f_locals again.
    - gh-108959: Fix caret placement for error locations for subscript
      and binary operations that involve non-semantic parentheses and
      spaces. Patch by Pablo Galindo
  - Library
    - gh-108682: Enum: require names=() or type=... to create an empty
      enum using the functional syntax.
    - gh-108843: Fix an issue in ast.unparse() when unparsing
      f-strings containing many quote types.
  - Documentation
    - gh-102823: Document the return type of x // y when x and y have
      type float.
  - Tests
    - gh-109396: Fix test_socket.test_hmac_sha1() in FIPS mode. Use a
      longer key: FIPS mode requires at least of at least 112 bits.
      The previous key was only 32 bits. Patch by Victor Stinner.
    - gh-104736: Fix test_gdb on Python built with LLVM clang 16 on
      Linux ppc64le (ex: Fedora 38). Search patterns in gdb “bt”
      command output to detect when gdb fails to retrieve the
      traceback. For example, skip a test if Backtrace stopped: frame
      did not save the PC is found. Patch by Victor Stinner.
    - gh-109237: Fix test_site.test_underpth_basic() when the working
      directory contains at least one non-ASCII character: encode the
      ._pth file to UTF-8 and enable the UTF-8 Mode to use UTF-8 for
      the child process stdout. Patch by Victor Stinner.
    - gh-109230: Fix test_pyexpat.test_exception(): it can now be run
      from a directory different than Python source code directory.
      Before, the test failed in this case. Skip the test if
      Modules/pyexpat.c source is not available. Skip also the test on
      Python implementations other than CPython. Patch by Victor
      Stinner.
    - gh-109015: Fix test_asyncio, test_imaplib and test_socket tests
      on FreeBSD if the TCP blackhole is enabled (sysctl
      net.inet.tcp.blackhole). Skip the few tests which failed with
      ETIMEDOUT which such non standard configuration. Currently, the
      FreeBSD GCP image enables TCP and UDP blackhole (sysctl
      net.inet.tcp.blackhole=2 and sysctl net.inet.udp.blackhole=1).
      Patch by Victor Stinner.
    - gh-91960: Skip test_gdb if gdb is unable to retrieve Python
      frame objects: if a frame is <optimized out>. When Python is
      built with “clang -Og”, gdb can fail to retrive the frame
      parameter of _PyEval_EvalFrameDefault(). In this case, tests
      like py_bt() are likely to fail. Without getting access to
      Python frames, python-gdb.py is mostly clueless on retrieving
      the Python traceback. Moreover, test_gdb is no longer skipped on
      macOS if Python is built with Clang. Patch by Victor Stinner.
    - gh-108962: Skip test_tempfile.test_flags() if chflags() fails
      with “OSError: [Errno 45] Operation not supported” (ex: on
      FreeBSD 13). Patch by Victor Stinner.
    - gh-108851: Fix test_tomllib recursion tests for WASI buildbots:
      reduce the recursion limit and compute the maximum nested
      array/dict depending on the current available recursion limit.
      Patch by Victor Stinner.
    - gh-108851: Add get_recursion_available() and
      get_recursion_depth() functions to the test.support module.
      Patch by Victor Stinner.
    - gh-108834: Add --fail-rerun option option to regrtest: if a test
      failed when then passed when rerun in verbose mode, exit the
      process with exit code 2 (error), instead of exit code 0
      (success). Patch by Victor Stinner.
    - gh-108834: Rename regrtest --verbose2 option (-w) to --rerun.
      Keep --verbose2 as a deprecated alias. Patch by Victor Stinner.
    - gh-108834: When regrtest reruns failed tests in verbose mode
      (./python -m test --rerun), tests are now rerun in fresh worker
      processes rather than being executed in the main process. If a
      test does crash or is killed by a timeout, the main process can
      detect and handle the killed worker process. Tests are rerun in
      parallel if the -jN option is used to run tests in parallel.
      Patch by Victor Stinner.
    - gh-103186: Suppress and assert expected RuntimeWarnings in
      test_sys_settrace.py
  - Build
    - gh-108740: Fix a race condition in make regen-all. The
      deepfreeze.c source and files generated by Argument Clinic are
      now generated or updated before generating “global objects”.
      Previously, some identifiers may miss depending on the order in
      which these files were generated. Patch by Victor Stinner.
- Python 3.12.0 release candidate 2:
  - Security
    - gh-108310: Fixed an issue where instances of ssl.SSLSocket were
      vulnerable to a bypass of the TLS handshake and included
      protections (like certificate verification) and treating sent
      unencrypted data as if it were post-handshake TLS encrypted
      data. Security issue reported as CVE-2023-40217 by Aapo Oksman.
      Patch by Gregory P. Smith.
    - gh-107774: PEP 669 specifies that
      sys.monitoring.register_callback will generate an audit event.
      Pre-releases of Python 3.12 did not generate the audit event.
      This is now fixed.
  - Core and Builtins
    - gh-108520: Fix
      multiprocessing.synchronize.SemLock.__setstate__() to properly
      initialize multiprocessing.synchronize.SemLock._is_fork_ctx.
      This fixes a regression when passing a SemLock accross nested
      processes.
    - Rename multiprocessing.synchronize.SemLock.is_fork_ctx to
      multiprocessing.synchronize.SemLock._is_fork_ctx to avoid
      exposing it as public API.
    - gh-108654: Restore locals shadowed by an inlined comprehension
      if the comprehension raises an exception.
    - gh-108487: Change an assert that would cause a spurious crash in
      a devious case that should only trigger deoptimization.
    - gh-106176: Use a WeakValueDictionary to track the lists
      containing the modules each thread is currently importing. This
      helps avoid a reference leak from keeping the list around longer
      than necessary. Weakrefs are used as GC can’t interrupt the
      cleanup.
    - gh-107901: Fix missing line number on JUMP_BACKWARD at the end
      of a for loop.
    - gh-108390: Raise an exception when setting a non-local event
      (RAISE, EXCEPTION_HANDLED, etc.) in
      sys.monitoring.set_local_events.
    - Fixes crash when tracing in recursive calls to Python classes.
    - gh-91051: Fix abort / segfault when using all eight type watcher
      slots, on platforms where char is signed by default.
    - gh-107724: In pre-release versions of 3.12, up to rc1, the
      sys.monitoring callback function for the PY_THROW event was
      missing the third, exception argument. That is now fixed.
    - gh-107080: Trace refs builds (--with-trace-refs) were crashing
      when used with isolated subinterpreters. The problematic global
      state has been isolated to each interpreter. Other fixing the
      crashes, this change does not affect users.
    - gh-77377: Ensure that multiprocessing synchronization objects
      created in a fork context are not sent to a different process
      created in a spawn context. This changes a segfault into an
      actionable RuntimeError in the parent process.
  - Library
    - gh-108469: ast.unparse() now supports new f-string syntax
      introduced in Python 3.12. Note that the f-string quotes are
      reselected for simplicity under the new syntax. (Patch by Steven
      Sun)
    - gh-108682: Enum: raise TypeError if super().__new__() is called
      from a custom __new__.
    - gh-108295: Fix crashes related to use of weakrefs on
      typing.TypeVar.
    - gh-64662: Fix support for virtual tables in
      sqlite3.Connection.iterdump(). Patch by Aviv Palivoda.
    - gh-108111: Fix a regression introduced in gh-101251 for 3.12,
      resulting in an incorrect offset calculation in
      gzip.GzipFile.seek().
    - gh-105736: Harmonized the pure Python version of OrderedDict
      with the C version. Now, both versions set up their internal
      state in __new__. Formerly, the pure Python version did the set
      up in __init__.
    - gh-108083: Fix bugs in the constructor of sqlite3.Connection and
      sqlite3.Connection.close() where exceptions could be leaked.
      Patch by Erlend E. Aasland.
    - gh-107963: Fix multiprocessing.set_forkserver_preload() to check
      the given list of modules names. Patch by Dong-hee Na.
    - gh-106242: Fixes os.path.normpath() to handle embedded null
      characters without truncating the path.
    - gh-107913: Fix possible losses of errno and winerror values in
      OSError exceptions if they were cleared or modified by the
      cleanup code before creating the exception object.
    - gh-107845: tarfile.data_filter() now takes the location of
      symlinks into account when determining their target, so it will
      no longer reject some valid tarballs with
      LinkOutsideDestinationError.
    - gh-107805: Fix signatures of module-level generated functions in
      turtle.
    - gh-107715: Fix doctest.DocTestFinder.find() in presence of class
      names with special characters. Patch by Gertjan van Zwieten.
    - gh-100814: Passing a callable object as an option value to a
      Tkinter image now raises the expected TclError instead of an
      AttributeError.
    - gh-106684: Close asyncio.StreamWriter when it is not closed by
      application leading to memory leaks. Patch by Kumar Aditya.
    - gh-107396: tarfiles; Fixed use before assignment of
      self.exception for gzip decompression
    - gh-106052: re module: fix the matching of possessive quantifiers
      in the case of a subpattern containing backtracking.
    - gh-100061: Fix a bug that causes wrong matches for regular
      expressions with possessive qualifier.
    - gh-99203: Restore following CPython <= 3.10.5 behavior of
      shutil.make_archive(): do not create an empty archive if
      root_dir is not a directory, and, in that case, raise
      FileNotFoundError or NotADirectoryError regardless of format
      choice. Beyond the brought-back behavior, the function may now
      also raise these exceptions in dry_run mode.
  - Documentation
    - gh-105052: Update timeit doc to specify that time in seconds is just the default.
  - Tests
    - gh-89392: Removed support of test_main() function in tests. They
      now always use normal unittest test runner.
    - gh-108388: Convert test_concurrent_futures to a package of 7
      sub-tests. Patch by Victor Stinner.
    - gh-108388: Split test_multiprocessing_fork,
      test_multiprocessing_forkserver and test_multiprocessing_spawn
      into test packages. Each package is made of 4 sub-tests:
      processes, threads, manager and misc. It allows running more
      tests in parallel and so reduce the total test duration. Patch
      by Victor Stinner.
    - gh-105776: Fix test_cppext when the C compiler command -std=c11
      option: remove -std= options from the compiler command. Patch by
      Victor Stinner.
    - gh-107178: Add the C API test for functions in the Mapping
      Protocol, the Sequence Protocol and some functions in the Object
      Protocol.
  - Build
    - gh-63760: Fix Solaris build: no longer redefine the
      gethostname() function. Solaris defines the function since 2005.
      Patch by Victor Stinner, original patch by Jakub Kulík.
    - gh-107814: When calling find_python.bat with -q it did not
      properly silence the output of nuget. That is now fixed.
  - Windows
    - gh-107565: Update Windows build to use OpenSSL 3.0.10.
    - gh-106242: Fixes realpath() to behave consistently when passed a
      path containing an embedded null character on Windows. In strict
      mode, it now raises OSError instead of the unexpected
      ValueError, and in non-strict mode will make the path absolute.
    - gh-106844: Fix integer overflow and truncating by the null
      character in _winapi.LCMapStringEx() which affects
      ntpath.normcase().
  - macOS
    - gh-107565: Update macOS installer to use OpenSSL 3.0.10.
  - Tools/Demos
    - gh-107565: Update multissltests and GitHub CI workflows to use
      OpenSSL 1.1.1v, 3.0.10, and 3.1.2.
    - gh-95065: Argument Clinic now supports overriding automatically
      generated signature by using directive @text_signature.
  - C API
    - gh-107916: C API functions PyErr_SetFromErrnoWithFilename(),
      PyErr_SetExcFromWindowsErrWithFilename() and
      PyErr_SetFromWindowsErrWithFilename() save now the error code
      before calling PyUnicode_DecodeFSDefault().
    - gh-107915: Such C API functions as PyErr_SetString(),
      PyErr_Format(), PyErr_SetFromErrnoWithFilename() and many others
      no longer crash or ignore errors if it failed to format the
      error message or decode the filename. Instead, they keep a
      corresponding error.
    - gh-107810: Improve DeprecationWarning for uses of PyType_Spec
      with metaclasses that have custom tp_new.

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