Fix merge conflicts.

Author: ZeroIntensity

.github/workflows/posix-deps-apt.sh

@@ -26,9 +26,16 @@ apt-get -yq --no-install-recommends install \
     xvfb \
     zlib1g-dev
 
-# Workaround missing libmpdec-dev on ubuntu 24.04:
-# https://launchpad.net/~ondrej/+archive/ubuntu/php
-# https://deb.sury.org/
-sudo add-apt-repository ppa:ondrej/php
-apt-get update
-apt-get -yq --no-install-recommends install libmpdec-dev
+# Workaround missing libmpdec-dev on ubuntu 24.04 by building mpdecimal
+# from source. ppa:ondrej/php (launchpad.net) are unreliable 
+# (https://status.canonical.com) so fetch the tarball directly
+# from the upstream host.
+# https://www.bytereef.org/mpdecimal/
+MPDECIMAL_VERSION=4.0.1
+curl -fsSL "https://www.bytereef.org/software/mpdecimal/releases/mpdecimal-${MPDECIMAL_VERSION}.tar.gz" \
+    | tar -xz -C /tmp
+(cd "/tmp/mpdecimal-${MPDECIMAL_VERSION}" \
+    && ./configure --prefix=/usr/local \
+    && make -j"$(nproc)" \
+    && make install)
+ldconfig

Doc/c-api/perfmaps.rst

@@ -31,7 +31,7 @@ Note that holding an :term:`attached thread state` is not required for these API
    or ``-2`` on failure to create a lock. Check ``errno`` for more information
    about the cause of a failure.
 
-.. c:function:: int PyUnstable_WritePerfMapEntry(const void *code_addr, unsigned int code_size, const char *entry_name)
+.. c:function:: int PyUnstable_WritePerfMapEntry(const void *code_addr, size_t code_size, const char *entry_name)
 
    Write one single entry to the ``/tmp/perf-$pid.map`` file. This function is
    thread safe. Here is what an example entry looks like::

Doc/deprecations/pending-removal-in-3.20.rst

@@ -38,3 +38,8 @@ Pending removal in Python 3.20
   - :mod:`zlib`
 
   (Contributed by Hugo van Kemenade and Stan Ulbrych in :gh:`76007`.)
+
+* :mod:`ast`:
+
+  * Creating instances of abstract AST nodes (such as :class:`ast.AST`
+    or :class:`!ast.expr`) is deprecated and will raise an error in Python 3.20.

Doc/faq/programming.rst

@@ -1924,7 +1924,7 @@ correctly using identity tests:
 
    .. code-block:: python
 
-      _sentinel = object()
+      _sentinel = sentinel('_sentinel')
 
       def pop(self, key, default=_sentinel):
           if key in self:

Doc/howto/descriptor.rst

@@ -594,7 +594,7 @@ a pure Python equivalent:
 
     def object_getattribute(obj, name):
         "Emulate PyObject_GenericGetAttr() in Objects/object.c"
-        null = object()
+        null = sentinel('null')
         objtype = type(obj)
         cls_var = find_name_in_mro(objtype, name, null)
         descr_get = getattr(type(cls_var), '__get__', null)
@@ -1635,12 +1635,12 @@ by member descriptors:
 
 .. testcode::
 
-    null = object()
+    null = sentinel('null')
 
     class Member:
 
         def __init__(self, name, clsname, offset):
-            'Emulate PyMemberDef in Include/structmember.h'
+            'Emulate PyMemberDef in Include/descrobject.h'
             # Also see descr_new() in Objects/descrobject.c
             self.name = name
             self.clsname = clsname

Doc/howto/perf_profiling.rst

@@ -217,8 +217,9 @@ Example, using the :mod:`sys` APIs in file :file:`example.py`:
 How to obtain the best results
 ------------------------------
 
-For best results, Python should be compiled with
-``CFLAGS="-fno-omit-frame-pointer -mno-omit-leaf-frame-pointer"`` as this allows
+For best results, keep frame pointers enabled. On supported GCC-compatible
+toolchains, CPython builds itself with ``-fno-omit-frame-pointer`` and, when
+available, ``-mno-omit-leaf-frame-pointer`` by default. These flags allow
 profilers to unwind using only the frame pointer and not on DWARF debug
 information. This is because as the code that is interposed to allow ``perf``
 support is dynamically generated it doesn't have any DWARF debugging information

Doc/library/ast.rst

@@ -42,7 +42,7 @@ Node classes
 
 .. class:: AST
 
-   This is the base of all AST node classes.  The actual node classes are
+   This is the abstract base of all AST node classes.  The actual node classes are
    derived from the :file:`Parser/Python.asdl` file, which is reproduced
    :ref:`above <abstract-grammar>`.  They are defined in the :mod:`!_ast` C
    module and re-exported in :mod:`!ast`.
@@ -168,6 +168,15 @@ Node classes
    arguments that were set as attributes of the AST node, even if they did not
    match any of the fields of the AST node. These cases now raise a :exc:`TypeError`.
 
+.. deprecated-removed:: next 3.20
+
+    In the :ref:`grammar above <abstract-grammar>`, the AST node classes that
+    correspond to production rules with variants (aka "sums") are abstract
+    classes. Previous versions of Python allowed for the creation of direct
+    instances of these abstract node classes. This behavior is deprecated and
+    will be removed in Python 3.20.
+
+
 .. note::
     The descriptions of the specific node classes displayed here
     were initially adapted from the fantastic `Green Tree
@@ -271,18 +280,25 @@ Root nodes
 Literals
 ^^^^^^^^
 
-.. class:: Constant(value)
+.. class:: Constant(value, kind)
 
    A constant value. The ``value`` attribute of the ``Constant`` literal contains the
    Python object it represents. The values represented can be instances of :class:`str`,
    :class:`bytes`, :class:`int`, :class:`float`, :class:`complex`, and :class:`bool`,
    and the constants :data:`None` and :data:`Ellipsis`.
 
+   The ``kind`` attribute is an optional string. For string literals with a
+   ``u`` prefix, ``kind`` is set to ``'u'``. For all other
+   constants, ``kind`` is ``None``.
+
    .. doctest::
 
         >>> print(ast.dump(ast.parse('123', mode='eval'), indent=4))
         Expression(
             body=Constant(value=123))
+        >>> print(ast.dump(ast.parse("u'hello'", mode='eval'), indent=4))
+        Expression(
+            body=Constant(value='hello', kind='u'))
 
 
 .. class:: FormattedValue(value, conversion, format_spec)
@@ -2536,6 +2552,20 @@ and classes for traversing abstract syntax trees:
       Added the *color* parameter.
 
 
+.. function:: compare(a, b, /, *, compare_attributes=False)
+
+   Recursively compares two ASTs.
+
+   *compare_attributes* affects whether AST attributes are considered
+   in the comparison. If *compare_attributes* is ``False`` (default), then
+   attributes are ignored. Otherwise they must all be equal. This
+   option is useful to check whether the ASTs are structurally equal but
+   differ in whitespace or similar details. Attributes include line numbers
+   and column offsets.
+
+   .. versionadded:: 3.14
+
+
 .. _ast-compiler-flags:
 
 Compiler flags
@@ -2571,20 +2601,6 @@ effects on the compilation of a program:
    .. versionadded:: 3.8
 
 
-.. function:: compare(a, b, /, *, compare_attributes=False)
-
-   Recursively compares two ASTs.
-
-   *compare_attributes* affects whether AST attributes are considered
-   in the comparison. If *compare_attributes* is ``False`` (default), then
-   attributes are ignored. Otherwise they must all be equal. This
-   option is useful to check whether the ASTs are structurally equal but
-   differ in whitespace or similar details. Attributes include line numbers
-   and column offsets.
-
-   .. versionadded:: 3.14
-
-
 .. _ast-cli:
 
 Command-line usage

Doc/library/compression.zstd.rst

@@ -331,10 +331,14 @@ Compressing and decompressing data in memory
 
       If *max_length* is non-negative, the method returns at most *max_length*
       bytes of decompressed data. If this limit is reached and further
-      output can be produced, the :attr:`~.needs_input` attribute will
-      be set to ``False``. In this case, the next call to
+      output can be produced (or EOF is reached), the :attr:`~.needs_input`
+      attribute will be set to ``False``. In this case, the next call to
       :meth:`~.decompress` may provide *data* as ``b''`` to obtain
-      more of the output.
+      more of the output. The full content can thus be read like::
+
+        process_output(d.decompress(data, max_length))
+        while not d.eof and not d.needs_input:
+            process_output(d.decompress(b"", max_length))
 
       If all of the input data was decompressed and returned (either
       because this was less than *max_length* bytes, or because

Doc/library/email.policy.rst

@@ -403,11 +403,26 @@ added matters.  To illustrate::
    .. attribute:: utf8
 
       If ``False``, follow :rfc:`5322`, supporting non-ASCII characters in
-      headers by encoding them as "encoded words".  If ``True``, follow
-      :rfc:`6532` and use ``utf-8`` encoding for headers.  Messages
+      headers by encoding them as :rfc:`2047` "encoded words".  If ``True``,
+      follow :rfc:`6532` and use ``utf-8`` encoding for headers.  Messages
       formatted in this way may be passed to SMTP servers that support
       the ``SMTPUTF8`` extension (:rfc:`6531`).
 
+      When ``False``, the generator will raise
+      :exc:`~email.errors.HeaderWriteError` if any header includes non-ASCII
+      characters in a context where :rfc:`2047` does not permit encoded words.
+      This particularly applies to mailboxes ("addr-spec") with non-ASCII
+      characters, which can be created via
+      :class:`~email.headerregistry.Address`. To use a mailbox with a non-ASCII
+      domain name with ``utf8=False``, first encode the domain using the
+      third-party :pypi:`idna` or :pypi:`uts46` module or with
+      :mod:`encodings.idna`. It is not possible to use a non-ASCII username
+      ("local-part") in a mailbox when ``utf8=False``.
+
+      .. versionchanged:: 3.15
+         Can trigger the raising of :exc:`~email.errors.HeaderWriteError`.
+         (Earlier versions incorrectly applied :rfc:`2047` in certain contexts,
+         mostly notably in addr-specs.)
 
    .. attribute:: refold_source
 

Doc/library/statistics.rst

@@ -713,7 +713,7 @@ However, for reading convenience, most of the examples show sorted sequences.
 
 .. function:: covariance(x, y, /)
 
-   Return the sample covariance of two inputs *x* and *y*. Covariance
+   Return the sample covariance of two sequence inputs *x* and *y*. Covariance
    is a measure of the joint variability of two inputs.
 
    Both inputs must be of the same length (no less than two), otherwise
@@ -739,7 +739,7 @@ However, for reading convenience, most of the examples show sorted sequences.
 
    Return the `Pearson's correlation coefficient
    <https://en.wikipedia.org/wiki/Pearson_correlation_coefficient>`_
-   for two inputs. Pearson's correlation coefficient *r* takes values
+   for two sequence inputs. Pearson's correlation coefficient *r* takes values
    between -1 and +1. It measures the strength and direction of a linear
    relationship.
 
@@ -802,7 +802,7 @@ However, for reading convenience, most of the examples show sorted sequences.
    (it is equal to the difference between predicted and actual values
    of the dependent variable).
 
-   Both inputs must be of the same length (no less than two), and
+   Both inputs must be sequences of the same length (no less than two), and
    the independent variable *x* cannot be constant;
    otherwise a :exc:`StatisticsError` is raised.