NEWS

+++++++++++
Python News
+++++++++++

(editors: check NEWS.help for information about editing NEWS using ReST.)

What's New in Python 2.5.6?
===========================

*Release date: 26-May-2011*


What's New in Python 2.5.6c1?
=============================

*Release date: 17-Apr-2011*

Library
-------

- Issue #11442: Add a charset parameter to the Content-type in SimpleHTTPServer
  to avoid XSS attacks.

- Issue #11662: Make urllib and urllib2 ignore redirections if the
  scheme is not HTTP, HTTPS or FTP (CVE-2011-1521).

- Issue #8674: Fixed a number of incorrect or undefined-behaviour-inducing
  overflow checks in the audioop module (CVE-2010-1634).

- Issue #7673: Fix security vulnerability (CVE-2010-2089) in the audioop
  module, ensure that the input string length is a multiple of the frame size.


What's New in Python 2.5.5?
===========================

*Release date: 31-Jan-2010*


What's New in Python 2.5.5c2?
=============================

*Release date: 24-Jan-2010*

Extension Modules
-----------------

- expat: Fix DoS via XML document with malformed UTF-8 sequences
  (CVE_2009_3560).

- expat: Fix DoS via malformed XML (CVE-2009-3720).


What's New in Python 2.5.5c1?
=============================

*Release date: 14-Jan-2010*

Core and builtins
-----------------

- Issue #6990: Fix threading.local subclasses leaving old state around
  after a reference cycle GC which could be recycled by new locals.

Library
-------

- Issue #7403: logging: Fixed possible race condition in lock creation.

- Issue #5068: Fixed the tarfile._BZ2Proxy.read() method that would loop
  forever on incomplete input. That caused tarfile.open() to hang when used
  with mode 'r' or 'r:bz2' and a fileobj argument that contained no data or
  partial bzip2 compressed data.


What's New in Python 2.5.4?
===========================

*Release date: 23-Dec-2008*

Core and builtins
-----------------

- Issue #5389: Avoid potential for undefined variable 'startinpos' in
  PyUnicode_DecodeUTF7().

- Revert patch for #1706039, as it can crash the interpreter.

- Added test case to ensure attempts to read from a file opened for writing
  fail.


What's New in Python 2.5.3?
===========================

*Release date: 19-Dec-2008*


Build
-----

- In the OSX installer, update SQLite to 3.6.7, and change bsddb URL.
  Build against system Tcl framework.

What's New in Python 2.5.3c1?
=============================

*Release date: 13-Dec-2008*

Core and builtins
-----------------

- Issue #1706039: Support continued reading from a file even after 
  EOF was hit.

- Issue #1683: prevent forking from interfering in threading storage.

- Issue #4597: Fixed several opcodes that weren't always propagating
  exceptions.

- Issue #4589: Propagated an exception thrown by a context manager's
  __exit__ method's result while it's being converted to bool.

- Issue #4317: Fixed a crash in the imageop.rgb2rgb8() function.

- Issue #4230: If ``__getattr__`` is a descriptor, it now functions correctly.

- Issue #4048: The parser module now correctly validates relative imports.

- Issue #4176: Fixed a crash when pickling an object which ``__reduce__``
  method does not return iterators for the 4th and 5th items.

- Issue #3967: Fixed a crash in the count() and find() methods of string-like
  objects, when the "start" parameter is a huge value.

- Issue #3936: The parser warnings for using "as" and "with" as variable names
  didn't fire after import statements.

- Issue #3751: str.rpartition would perform a left-partition when called with
  a unicode argument.

- Issue #3537: Fix an assertion failure when an empty but presized dict
  object was stored in the freelist.

- Apply security patches from Apple.

- Issue #2620: Overflow checking when allocating or reallocating memory
  was not always being done properly in some python types and extension
  modules.  PyMem_MALLOC, PyMem_REALLOC, PyMem_NEW and PyMem_RESIZE have
  all been updated to perform better checks and places in the code that
  would previously leak memory on the error path when such an allocation
  failed have been fixed.

- Issue #2242: Fix a crash when decoding invalid utf-7 input on certain
  Windows / Visual Studio versions.

- Issue #3360: Fix incorrect parsing of '020000000000.0', which
  produced a ValueError instead of giving the correct float.

- Issue #3242: Fix a crash inside the print statement, if sys.stdout is
  set to a custom object whose write() method happens to install
  another file in sys.stdout.

- Issue #3088: Corrected a race condition in classes derived from
  threading.local: the first member set by a thread could be saved in
  another thread's dictionary.

- Issue #3100: Corrected a crash on deallocation of a subclassed weakref which
  holds the last (strong) reference to its referent.

- Issue #1686386: Tuple's tp_repr did not take into account the possibility of
  having a self-referential tuple, which is possible from C code.  Nor did
  object's tp_str consider that a type's tp_str could do something that could
  lead to an inifinite recursion.  Py_ReprEnter() and Py_EnterRecursiveCall(),
  respectively, fixed the issues.  (Backport of r58288 from trunk.)

- Patch #1442: properly report exceptions when the PYTHONSTARTUP file
  cannot be executed.

- The compilation of a class nested in another class used to leak one
  reference on the outer class name.

- Issue #1477: With narrow Unicode builds, the unicode escape sequence
  \Uxxxxxxxx did not accept values outside the Basic Multilingual Plane.  This
  affected raw unicode literals and the 'raw-unicode-escape' codec.  Now
  UTF-16 surrogates are generated in this case, like normal unicode literals
  and the 'unicode-escape' codec.

- Issue #2321: use pymalloc for unicode object string data to reduce
  memory usage in some circumstances.

- Issue #2238: Some syntax errors in *args and **kwargs expressions could give
  bogus error messages.

- Issue #2587: In the C API, PyString_FromStringAndSize() takes a signed size
  parameter but was not verifying that it was greater than zero.  Values
  less than zero will now raise a SystemError and return NULL to indicate a
  bug in the calling C code.

- Issue #2588, #2589: Fix potential integer underflow and overflow
  conditions in the PyOS_vsnprintf C API function.

- Issue #1204: The configure script now tests for additional libraries
  that may be required when linking against readline.  This fixes issues
  with x86_64 builds on some platforms (a few Linux flavors and OpenBSD).

- Issue #3678: Correctly pass LDFLAGS and LDLAST to the linker on shared
  library targets in the Makefile.

Library
-------

- Issue #3767: Convert Tk object to string in tkColorChooser.

- Issue #4342: Always convert Text.index result to string.

- Issue 3248: Allow placing ScrolledText in a PanedWindow.

- Issue #4084: Fix max, min, max_mag and min_mag Decimal methods to
  give correct results in the case where one argument is a quiet NaN
  and the other is a finite number that requires rounding.

- Issue #1776581 and #4302. Minor corrections to smtplib.

- Issue #3774: Fixed an error when create a Tkinter menu item without command
  and then remove it.

- Assigning methods to ctypes.Structure and ctypes.Union subclasses
  after creation of the class does now work correctly.  See Issue #1700288.

- Issue #3895: _lsprof could be crashed with an external timer that did not
  return a float when a Profiler object is garbage collected.

- Issues #3968 and #3969: two minor turtle problems.

- Issue #3547: Fixed ctypes structures bitfields of varying integer
  sizes.

- Issue #3762: platform.architecture() fails if python is lanched via
  its symbolic link.

- Issue #3554: ctypes.string_at and ctypes.wstring_at did call Python
  api functions without holding the GIL, which could lead to a fatal
  error when they failed.

- Issue #2234: distutils failed for some versions of the cygwin compiler. The
  version reported by these tools does not necessarily follow the python
  version numbering scheme, so the module is less strict when parsing it.

- Issue #2222: Fixed reference leak when occured os.rename()
  fails unicode conversion on 2nd parameter. (windows only)

- Issue #3134: shutil referenced undefined WindowsError symbol.

- Issue #1342811: Fix leak in Tkinter.Menu.delete. Commands associated to
  menu entries were not deleted.

- Issue #799428: Fix Tkinter.Misc._nametowidget to unwrap Tcl command objects.

- Issue #3339: dummy_thread.acquire() could return None which is not a valid
  return value.

- Issue #3116 and #1792:  Fix quadratic behavior in marshal.dumps().

- Issue #2682: ctypes callback functions no longer contain a cyclic
  reference to themselves.

- Issue #2670:  Fix a failure in urllib2.build_opener(), when passed two
  handlers that derive the same default base class.

- Issue #2495: tokenize.untokenize now inserts a space between two consecutive
  string literals; previously, ["" ""] was rendered as [""""], which is
  incorrect python code.

- Issue #2482: Make sure that the coefficient of a Decimal is always
  stored as a str instance, not as a unicode instance.  This ensures
  that str(Decimal) is always an instance of str.  This fixes a
  regression from Python 2.5.1 to Python 2.5.2.

- Issue #2478: fix failure of decimal.Decimal(0).sqrt()

- Issue #2432: give DictReader the dialect and line_num attributes
  advertised in the docs.

- Issue #1747858: Fix chown to work with large uid's and gid's on 64-bit
  platforms.

- Bug #2220: handle rlcompleter attribute match failure more gracefully.

- Bug #1725737: In distutil's sdist, exclude RCS, CVS etc. also in the
  root directory, and also exclude .hg, .git, .bzr, and _darcs.

- Bug #1389051: imaplib causes excessive memory fragmentation when reading
  large messages.

- Bug #1389051, 1092502: fix excessively large memory allocations when
  calling .read() on a socket object wrapped with makefile().

- Bug #1433694: minidom's .normalize() failed to set .nextSibling for
  last child element.

- Issue #2791: subprocess.Popen.communicate explicitly closes its
  stdout and stderr fds rather than leaving them open until the
  instance is destroyed.

- Issue #2632: Prevent socket.read(bignumber) from over allocating memory
  in the common case when the data is returned from the underlying socket
  in increments much smaller than bignumber.

- Issue #1857: subprocess.Popen.poll gained an additional _deadstate keyword
  argument in python 2.5, this broke code that subclassed Popen to include its
  own poll method.  Fixed my moving _deadstate to an _internal_poll method.

- Issue #2113: Fix error in subprocess.Popen if the select system call is
  interrupted by a signal.

- Issue #874900: after an os.fork() call the threading module state is cleaned
  up in the child process to prevent deadlock and report proper thread counts
  if the new process uses the threading module.

- Issue #3309: Fix bz2.BZFile iterator to release its internal lock
  properly when raising an exception due to the bz2file being closed.
  Prevents a deadlock.


Extension Modules
-----------------

- Issue #1040026: Fix os.times result on systems where HZ is incorrect.

- Issue #4228: Pack negative values the same way as 2.4 in struct's L format.

- Security Issue #2: imageop did not validate arguments correctly and could
  segfault as a result.

- Issue 3886: [CVE-2008-2316] Possible integer overflow in the _hashopenssl
  module was closed.

- Issue 1179: [CVE-2007-4965] Integer overflow in imageop module.
  Also fixes rgbimg module.

- Issue #3205: When iterating over a BZ2File fails allocating memory, raise
  a MemoryError rather than silently stop the iteration.

- Patch #2111: Avoid mmap segfault when modifying a PROT_READ block.

- zlib.decompressobj().flush(value) no longer crashes the interpreter when
  passed a value less than or equal to zero.

- issue2858: Fix potential memory corruption when bsddb.db.DBEnv.lock_get
  and other bsddb.db object constructors raised an exception.

- Issue #3120: On 64-bit Windows the subprocess module was truncating handles.

- Issue #1471: Arguments to fcntl.ioctl are no longer broken on 64-bit OpenBSD
  and similar platforms due to sign extension.

- Issue #3312: Fix two crashes in sqlite3.


Tests
-----

- Issue #3863: Disabled a unit test of fork being called from a thread
  when running on platforms known to exhibit OS bugs when attempting that.

- Issue #3261: test_cookielib had an improper file encoding specified.

- Patch #2232: os.tmpfile might fail on Windows if the user has no
  permission to create files in the root directory.


Documentation
-------------

Build
-----

- Issue #4368: Don't define _XOPEN_SOURCE on FreeBSD 4.*.

Windows
-------


What's New in Python 2.5.2?
===========================

*Release date: 21-Feb-2008*

Extension Modules
-----------------

- Fix deallocation of array objects when allocation ran out of memory.
  Remove array test case that was incorrect on 64-bit systems.

- Bug #2137: Remove test_struct.test_crasher, which was meaningful
  only on 32-bit systems.


What's New in Python 2.5.2c1?
=============================

*Release date: 14-Feb-2008*

Core and builtins
-----------------

- Added checks for integer overflows, contributed by Google. Some are
  only available if asserts are left in the code, in cases where they
  can't be triggered from Python code.

- Issue #2045: Fix an infinite recursion triggered when printing a subclass of
  collections.defaultdict, if its default_factory is set to a bound method.

- Issue #1920: "while 0" statements were completely removed by the compiler,
  even in the presence of an "else" clause, which is supposed to be run when
  the condition is false. Now the compiler correctly emits bytecode for the
  "else" suite.

- A few crashers fixed: weakref_in_del.py (issue #1377858);
  loosing_dict_ref.py (issue #1303614, test67.py);
  borrowed_ref_[34].py (not in tracker).

- Fix for #1303614 and #1174712 backported from the trunk:
  __dict__ descriptor abuse for subclasses of built-in types;
  subclassing from both ModuleType and another built-in types.

- Bug #1915: Python compiles with --enable-unicode=no again. However
  several extension methods and modules do not work without unicode
  support.

- Issue #1678380: distinction between 0.0 and -0.0 was lost during constant
  folding optimization.  This was a regression from Python 2.4.

- Issue #1882: when compiling code from a string, encoding cookies in the
  second line of code were not always recognized correctly.

- Bug #1517: Possible segfault in lookup().

- Issue #1638: %zd configure test fails on Linux.

- Issue #1553: An erroneous __length_hint__ can make list() raise a
  SystemError.

- Issue #1521: On 64bit platforms, using PyArgs_ParseTuple with the t# of w#
  format code incorrectly truncated the length to an int, even when
  PY_SSIZE_T_CLEAN is set.  The str.decode method used to return incorrect
  results with huge strings.

- Issue #1445: Fix a SystemError when accessing the ``cell_contents``
  attribute of an empty cell object.

- Issue #1265: Fix a problem with sys.settrace, if the tracing function uses a
  generator expression when at the same time the executed code is closing a
  paused generator.

- Issue 1704621: Fix segfaults in list_repeat() and list_inplace_repeat().

- Issue #1147: Generators were not raising a DeprecationWarning when a string
  was passed into throw().

- Patch #1031213: Decode source line in SyntaxErrors back to its original source
  encoding.

- Patch #1673759: add a missing overflow check when formatting floats
  with %G.

- Patch #1733960: Allow T_LONGLONG to accept ints.

- Prevent expandtabs() on string and unicode objects from causing a segfault
  when a large width is passed on 32-bit platforms.

- Bug #1733488: Fix compilation of bufferobject.c on AIX.

- Fix Issue #1703448: A joined thread could show up in the
  threading.enumerate() list after the join() for a brief period until
  it actually exited.


Library
-------

- curses.textpad: Fix off-by-one error that resulted in characters
  being missed from the contents of a Textbox.

- Patch #1966: Break infinite loop in httplib when the servers
  implements the chunked encoding incorrectly.

- tarfile.py: Fix reading of xstar archives.

- #2021: Allow tempfile.NamedTemporaryFile to be used in with statements
  by correctly supporting the context management protocol.

- Fixed _ctypes.COMError so that it must be called with exactly three
  arguments, instances now have the hresult, text, and details
  instance variables.

- #1507247, #2004: tarfile.py: Use mode 0700 for temporary directories and
  default permissions for missing directories.

- #175006: The debugger used to skip the condition of a "while" statement
  after the first iteration. Now it correctly steps on the expression, and
  breakpoints on the "while" statement are honored on each loop.

- The ctypes int types did not accept objects implementing
  __int__() in the constructor.

- #1189216: Fix the zipfile module to work on archives with headers
  past the 2**31 byte boundary.

- Issue #1336: fix a race condition in subprocess.Popen if the garbage
  collector kicked in at the wrong time that would cause the process
  to hang when the child wrote to stderr.

- Bug #1687: Fixed plistlib.py restricts <integer> to Python int when writing.

- Issue #1182: many arithmetic bugs in the decimal module have been
  fixed, and the decimal module has been updated to comply with the
  latest IBM Decimal Arithmetic specification (version 1.66) and
  testsuite (version 2.57).  (Backported from Python 2.6a0.)

- Patch #1637: fix urlparse for URLs like 'http://x.com?arg=/foo'.

- Issue #1735: TarFile.extractall() now correctly sets directory permissions
  and times.

- Bug #1713: posixpath.ismount() claims symlink to a mountpoint is a mountpoint.

- Issue #1700: Regular expression inline flags incorrectly handle certain
  unicode characters.

- Change ctypes version number to 1.0.3 (when Python 2.5.2 is released,
  ctypes 1.0.3 will be also be released).

- Issue #1695: Fixed typo in the docstrings for time.localtime() and gmtime().

- Issue #1642: Fix segfault in ctypes when trying to delete attributes.

- os.access now returns True on Windows for any existing directory.

- Issue #1531: tarfile.py: Read fileobj from the current offset, do not
  seek to the start.

- Issue 1429818: patch for trace and doctest modules so they play nicely
  together.

- doctest mis-used __loader__.get_data(), assuming universal newlines was used.

- Issue #1705170: contextlib.contextmanager was still swallowing
  StopIteration in some cases. This should no longer happen.

- Bug #1307: Fix smtpd so it doesn't raise an exception when there is no arg.

- ctypes will now work correctly on 32-bit systems when Python is
  configured with --with-system-ffi.

- Bug #1777530: ctypes.util.find_library uses dump(1) instead of
  objdump(1) on Solaris.

- Bug #1153: repr.repr() now doesn't require set and dictionary items
  to be orderable to properly represent them.

- Bug #1709599: Run test_1565150 only if the file system is NTFS.

- When encountering a password-protected robots.txt file the RobotFileParser
  no longer prompts interactively for a username and password (bug 813986).

- TarFile.__init__() no longer fails if no name argument is passed and
  the fileobj argument has no usable name attribute (e.g. StringIO).

- Reverted the fix for bug #1548891 because it broke compatibility with
  arbitrary read buffers. Added a note in the documentation.

- GB18030 codec now can encode additional two-byte characters that
  are missing in GBK.

- Bug #1704793: Raise KeyError if unicodedata.lookup cannot
  represent the result in a single character.

- Change location of the package index to pypi.python.org/pypi

- Bug #1701409: Fix a segfault in printing ctypes.c_char_p and
  ctypes.c_wchar_p when they point to an invalid location.  As a
  sideeffect the representation of these instances has changed.

- Bug #1734723: Fix repr.Repr() so it doesn't ignore the maxtuple attribute.

- Bug #1728403: Fix a bug that CJKCodecs StreamReader hangs when it
  reads a file that ends with incomplete sequence and sizehint argument
  for .read() is specified.

- Bug #1730389: Have time.strptime() match spaces in a format argument with
  ``\s+`` instead of ``\s*``.

- SF 1668596/1720897: distutils now copies data files
  even if package_dir is empty.

- Fix bug in marshal where bad data would cause a segfault due to
  lack of an infinite recursion check.

- mailbox.py: Ignore stray directories found in Maildir's cur/new/tmp
  subdirectories.

- HTML-escape the plain traceback in cgitb's HTML output, to prevent
  the traceback inadvertently or maliciously closing the comment and
  injecting HTML into the error page.

- Bug #1290505: Properly clear time.strptime's locale cache when the locale
  changes between calls.  Backport of r54646 and r54647.

- Bug #1706381: Specifying the SWIG option "-c++" in the setup.py file
  (as opposed to the command line) will now write file names ending in
  ".cpp" too.

- Patch #1695229: Fix a regression with tarfile.open() and a missing name
  argument.

- tarfile.py: Fix directory names to have only one trailing slash.

- Fix test_pty.py to not hang on OS X (and theoretically other *nixes) when
  run in verbose mode.

- Bug #1693258: IDLE would show two "Preferences" menu's with some versions
  of Tcl/Tk

- Issue1385: The hmac module now computes the correct hmac when using hashes
  with a block size other than 64 bytes (such as sha384 and sha512).

- Issue829951: In the smtplib module, SMTP.starttls() now complies with
  RFC 3207 and forgets any knowledge obtained from the server not obtained
  from the TLS negotiation itself.  Patch contributed by Bill Fenner.


Extension Modules
-----------------

- Patch #1736: Fix file name handling of _msi.FCICreate.

- Backport r59862 (issue #712900): make long regexp matches interruptable.

- #1940: make it possible to use curses.filter() before curses.initscr()
  as the documentation says.

- Fix a potential 'SystemError: NULL result without error' in _ctypes.

- Bug #1301: Bad assert in _tkinter fixed.

- Patch #1114: fix curses module compilation on 64-bit AIX, & possibly
  other 64-bit LP64 platforms where attr_t is not the same size as a long.
  (Contributed by Luke Mewburn.)

- Bug #1649098: Avoid declaration of zero-sized array declaration in
  structure.

- Bug #1703286: ctypes no longer truncates 64-bit pointers.

- Bug #1721309: prevent bsddb module from freeing random memory.

- Bug #1233: fix bsddb.dbshelve.DBShelf append method to work as
  intended for RECNO databases.

- Bug #1726026: Correct the field names of WIN32_FIND_DATAA and
  WIN32_FIND_DATAW structures in the ctypes.wintypes module.

- Added support for linking the bsddb module against BerkeleyDB 4.6.x.

- Fix libffi configure for hppa*-*-linux* | parisc*-*-linux*.

- Build using system ffi library on arm*-linux*.

- Bug #1372: zlibmodule.c: int overflow in PyZlib_decompress

- bsddb module: Fix memory leak when using database cursors on
  databases without a DBEnv.


Documentation
-------------

- Bug #1637365: add subsection about "__name__ == __main__" to the
  Python tutorial.

- Bug #1569057: Document that calling file.next() on a file open for writing
  has undefined behaviour.  Backport of r54712.

Build
-----

- Have the search path for building extensions follow the declared order in
  $CPPFLAGS and $LDFLAGS.

- Bug #1234: Fixed semaphore errors on AIX 5.2

- Bug #1699: Define _BSD_SOURCE only on OpenBSD.

- Bug #1608: use -fwrapv when GCC supports it.  This is important,
  newer GCC versions may optimize away overflow buffer overflow checks
  without this option!

- Allow simultaneous installation of 32-bit and 64-bit versions
  on 64-bit Windows systems.

- Patch #786737: Allow building in a tree of symlinks pointing to
  a readonly source.

- Bug #1737210: Change Manufacturer of Windows installer to PSF.

- Bug #1746880: Correctly install DLLs into system32 folder on Win64.

- Define _BSD_SOURCE, to get access to POSIX extensions on OpenBSD 4.1+.

- Patch #1673122: Use an explicit path to libtool when building a framework.
  This avoids picking up GNU libtool from a users PATH.

- Allow Emacs 22 for building the documentation in info format.

- Makefile.pre.in(buildbottest): Run an optional script pybuildbot.identify
  to include some information about the build environment.

Windows
-------

- Bug #1216: Restore support for Visual Studio 2002.

What's New in Python 2.5.1?
=============================

*Release date: 18-APR-2007*

Core and builtins
-----------------

- Bug #1722485: remove docstrings again when running with -OO.

- Revert SF #1615701: dict.update() does *not* call __getitem__() or keys()
  if subclassed.  This is to remain consistent with 2.5.
  Also revert revision 53667 with made a similar change to set.update().


What's New in Python 2.5.1c1?
=============================

*Release date: 05-APR-2007*

Core and builtins
-----------------

- Patch #1682205: a TypeError while unpacking an iterable is no longer
  masked by a generic one with the message "unpack non-sequence".

- Patch #1642547: Fix an error/crash when encountering syntax errors in
  complex if statements.

- Patch #1462488: Python no longer segfaults when ``object.__reduce_ex__()``
  is called with an object that is faking its type.

- Patch #1680015: Don't modify __slots__ tuple if it contains an unicode
  name.

- Patch #922167: Python no longer segfaults when faced with infinitely
  self-recursive reload() calls (as reported by bug #742342).

- Patch #1675981: remove unreachable code from ``type.__new__()`` method.

- Patch #1638879: don't accept strings with embedded NUL bytes in long().

- Bug #1674503: close the file opened by execfile() in an error condition.

- Patch #1674228: when assigning a slice (old-style), check for the
  sq_ass_slice instead of the sq_slice slot.

- Bug #1669182: prevent crash when trying to print an unraisable error
  from a string exception.

- The peephole optimizer left None as a global in functions with a docstring
  and an explicit return value.

- Bug #1653736: Properly discard third argument to slot_nb_inplace_power.

- SF #151204:  enumerate() now raises an Overflow error at sys.maxint items.

- Bug #1377858: Fix the segfaulting of the interpreter when an object created
  a weakref on itself during a __del__ call for new-style classes (classic
  classes still have the bug).

- Bug #1648179:  set.update() did not recognize an overridden __iter__
  method in subclasses of dict.

- Bug #1579370: Make PyTraceBack_Here use the current thread, not the
  frame's thread state.

- patch #1630975: Fix crash when replacing sys.stdout in sitecustomize.py

- Bug #1637022: Prefix AST symbols with _Py_.

- Prevent seg fault on shutdown which could occur if an object
  raised a warning.

- Bug #1566280: Explicitly invoke threading._shutdown from Py_Main,
  to avoid relying on atexit.

- Bug #1590891: random.randrange don't return correct value for big number

- Bug #1456209: In some obscure cases it was possible for a class with a
  custom ``__eq__()`` method to confuse set internals when class instances
  were used as a set's elements and the ``__eq__()`` method mutated the set.

- The repr for self-referential sets and fronzensets now shows "..." instead
  of falling into infinite recursion.

- Eliminated unnecessary repeated calls to hash() by set.intersection() and
  set.symmetric_difference_update().

- Bug #1591996: Correctly forward exception in instance_contains().

- Bug #1588287: fix invalid assertion for `1,2` in debug builds.

- Bug #1576657: when setting a KeyError for a tuple key, make sure that
  the tuple isn't used as the "exception arguments tuple".  Applied to
  both sets and dictionaries.

- Bug #1565514, SystemError not raised on too many nested blocks.

- Bug #1576174: WindowsError now displays the windows error code
  again, no longer the posix error code.

- Patch #1549049: Support long values in structmember.

- Bug #1542016: make sys.callstats() match its docstring and return an
  11-tuple (only relevant when Python is compiled with -DCALL_PROFILE).

- Bug #1545497: when given an explicit base, int() did ignore NULs
  embedded in the string to convert.

- Bug #1569998: break inside a try statement (outside a loop) is now
  recognized and rejected.

- Patch #1542451: disallow continue anywhere under a finally.

- list.pop(x) accepts any object x following the __index__ protocol.

- Fix some leftovers from the conversion from int to Py_ssize_t
  (relevant to strings and sequences of more than 2**31 items).

- A number of places, including integer negation and absolute value,
  were fixed to not rely on undefined behaviour of the C compiler
  anymore.

- Bug #1566800: make sure that EnvironmentError can be called with any
  number of arguments, as was the case in Python 2.4.

- Patch #1567691: super() and new.instancemethod() now don't accept
  keyword arguments any more (previously they accepted them, but didn't
  use them).

- Fix a bug in the parser's future statement handling that led to "with"
  not being recognized as a keyword after, e.g., this statement:
  from __future__ import division, with_statement

- Bug #1557232: fix seg fault with def f((((x)))) and def f(((x),)).

- Fix %zd string formatting on Mac OS X so it prints negative numbers.

- Allow exception instances to be directly sliced again.


Extension Modules
-----------------

- Patch #1643738: Problem with signals in a single-threaded application.

- Bug #1563759: struct.unpack doens't support buffer protocol objects.

- Bug #1686475: Support stat'ing open files on Windows again.

- Bug #1647541: Array module's buffer interface can now handle empty arrays.

- Bug #1693079: The array module can now successfully pickle empty arrays.

- Bug #1688393: Prevent crash in socket.recvfrom if length is negative.

- Bug #1622896: fix a rare corner case where the bz2 module raised an
  error in spite of a succesful compression.

- Patch #1654417: make operator.{get,set,del}slice use the full range
  of Py_ssize_t.

- Patch #1646728: datetime.fromtimestamp fails with negative
  fractional times.  With unittest.

- Patch #1494140: Add documentation for the new struct.Struct object.

- Patch #1657276: Make NETLINK_DNRTMSG conditional.

- Bug #1653736: Fix signature of time_isoformat.

- Issue #1698398 Zipfile.printdir() crashed because the format string
  expected a tuple type of length six instead of time.struct_time object.

- operator.count() now raises an OverflowError when the count reaches sys.maxint.

- Bug #1575169: operator.isSequenceType() now returns False for subclasses of dict.

- collections.defaultdict() now verifies that the factory function is callable.

- Bug #1486663: don't reject keyword arguments for subclasses of builtin
  types.

- The version number of the ctypes package was changed to "1.0.2".

- Bug #1664966: Fix crash in exec if Unicode filename can't be decoded.

- Patch #1544279: Improve thread-safety of the socket module by moving
  the sock_addr_t storage out of the socket object.

- Patch #1615868: make bz2.BZFile.seek() work for offsets >2GiB.

- Bug #1563807: _ctypes built on AIX fails with ld ffi error.

- Bug #1598620: A ctypes Structure cannot contain itself.

- Bug #1588217: don't parse "= " as a soft line break in binascii's
  a2b_qp() function, instead leave it in the string as quopri.decode()
  does.

- Patch #838546: Make terminal become controlling in pty.fork()

- Patch #1560695: Add .note.GNU-stack to ctypes' sysv.S so that
  ctypes isn't considered as requiring executable stacks.

- Bug #1567666: Emulate GetFileAttributesExA for Win95.

- Bug #1548891: The cStringIO.StringIO() constructor now encodes unicode
  arguments with the system default encoding just like the write()
  method does, instead of converting it to a raw buffer.

- Bug #1565150: Fix subsecond processing for os.utime on Windows.

- Patch #1572724: fix typo ('=' instead of '==') in _msi.c.

- Bug #1572832: fix a bug in ISO-2022 codecs which may cause segfault
  when encoding non-BMP unicode characters.

- Bug #1556784: allow format strings longer than 127 characters in
  datetime's strftime function.

- Fix itertools.count(n) to work with negative numbers again.

- Make regex engine raise MemoryError if allocating memory fails.

- fixed a bug with bsddb.DB.stat: the flags and txn keyword arguments
  were transposed.

- Added support for linking the bsddb module against BerkeleyDB 4.5.x.

- Modifying an empty deque during iteration now raises RuntimeError
  instead of StopIteration.

- Bug #1552726: fix polling at the interpreter prompt when certain
  versions of the readline library are in use.

- Bug #1633621: if curses.resizeterm() or curses.resize_term() is called,
  update _curses.LINES, _curses.COLS, curses.LINES and curses.COLS.

- Fix an off-by-one bug in locale.strxfrm().

Library
-------

- Patch #1685563: remove (don't add) duplicate paths in distutils.MSVCCompiler.

- Bug #978833: Revert r50844, as it broke _socketobject.dup.

- Bug #1675967: re patterns pickled with Python 2.4 and earlier can
  now be unpickled with Python 2.5.

- Bug #1684254: webbrowser now uses shlex to split any command lines
  given to get(). It also detects when you use '&' as the last argument
  and creates a BackgroundBrowser then.

- Patch #1681153: the wave module now closes a file object it opened if
  initialization failed.

- Bug #767111: fix long-standing bug in urllib which caused an
  AttributeError instead of an IOError when the server's response didn't
  contain a valid HTTP status line.

- Bug #1629369: Correctly parse multiline comment in address field.

- Bug #1582282: Fix email.header.decode_header() to properly treat encoded
  words with no delimiting whitespace as a single word.

- Patch #1449244: Support Unicode strings in
  email.message.Message.{set_charset,get_content_charset}.

- Patch #1542681: add entries for "with", "as" and "CONTEXTMANAGERS" to
  pydoc's help keywords.

- Patch #1192590: Fix pdb's "ignore" and "condition" commands so they trap
  the IndexError caused by passing in an invalid breakpoint number.