Merge branch 'master' into format-twos-compl/74756

Author: skirpichev

.github/CODEOWNERS

@@ -188,6 +188,7 @@ Python/ast_opt.c              @isidentical @eclips4
 Parser/asdl.py                @isidentical @JelleZijlstra @eclips4
 Parser/asdl_c.py              @isidentical @JelleZijlstra @eclips4
 Lib/ast.py                    @isidentical @JelleZijlstra @eclips4
+Lib/_ast_unparse.py           @isidentical @JelleZijlstra @eclips4
 Lib/test/test_ast/            @eclips4
 
 # Mock

Doc/c-api/type.rst

@@ -82,6 +82,9 @@ Type Objects
    error (e.g. no more watcher IDs available), return ``-1`` and set an
    exception.
 
+   In free-threaded builds, :c:func:`PyType_AddWatcher` is not thread-safe,
+   so it must be called at start up (before spawning the first thread).
+
    .. versionadded:: 3.12
 
 

Doc/library/dis.rst

@@ -76,7 +76,7 @@ the following command can be used to display the disassembly of
      2           RESUME                   0
    <BLANKLINE>
      3           LOAD_GLOBAL              1 (len + NULL)
-                 LOAD_FAST                0 (alist)
+                 LOAD_FAST_BORROW         0 (alist)
                  CALL                     1
                  RETURN_VALUE
 
@@ -215,7 +215,7 @@ Example:
     ...
     RESUME
     LOAD_GLOBAL
-    LOAD_FAST
+    LOAD_FAST_BORROW
     CALL
     RETURN_VALUE
 
@@ -1402,13 +1402,28 @@ iterations of the loop.
       This opcode is now only used in situations where the local variable is
       guaranteed to be initialized. It cannot raise :exc:`UnboundLocalError`.
 
+.. opcode:: LOAD_FAST_BORROW (var_num)
+
+   Pushes a borrowed reference to the local ``co_varnames[var_num]`` onto the
+   stack.
+
+   .. versionadded:: 3.14
+
 .. opcode:: LOAD_FAST_LOAD_FAST (var_nums)
 
    Pushes references to ``co_varnames[var_nums >> 4]`` and
    ``co_varnames[var_nums & 15]`` onto the stack.
 
    .. versionadded:: 3.13
 
+
+.. opcode:: LOAD_FAST_BORROW_LOAD_FAST_BORROW (var_nums)
+
+   Pushes borrowed references to ``co_varnames[var_nums >> 4]`` and
+   ``co_varnames[var_nums & 15]`` onto the stack.
+
+   .. versionadded:: 3.14
+
 .. opcode:: LOAD_FAST_CHECK (var_num)
 
    Pushes a reference to the local ``co_varnames[var_num]`` onto the stack,
@@ -2023,4 +2038,3 @@ instructions:
 
    .. deprecated:: 3.13
       All jumps are now relative. This list is empty.
-

Doc/library/linecache.rst

@@ -30,6 +30,10 @@ The :mod:`linecache` module defines the following functions:
 
    .. index:: triple: module; search; path
 
+   If *filename* indicates a frozen module (starting with ``'<frozen '``), the function
+   will attepmt to get the real file name from ``module_globals['__file__']`` if
+   *module_globals* is not ``None``.
+
    If a file named *filename* is not found, the function first checks
    for a :pep:`302` ``__loader__`` in *module_globals*.
    If there is such a loader and it defines a ``get_source`` method,
@@ -38,6 +42,10 @@ The :mod:`linecache` module defines the following functions:
    Finally, if *filename* is a relative filename,
    it is looked up relative to the entries in the module search path, ``sys.path``.
 
+   .. versionchanged:: 3.14
+
+      Support *filename* of frozen modules.
+
 
 .. function:: clearcache()
 

Doc/reference/compound_stmts.rst

@@ -232,6 +232,8 @@ Additional information on exceptions can be found in section :ref:`exceptions`,
 and information on using the :keyword:`raise` statement to generate exceptions
 may be found in section :ref:`raise`.
 
+.. versionchanged:: next
+   Support for optionally dropping grouping parentheses when using multiple exception types. See :pep:`758`.
 
 .. _except:
 
@@ -247,7 +249,8 @@ An expression-less :keyword:`!except` clause, if present, must be last;
 it matches any exception.
 
 For an :keyword:`!except` clause with an expression, the
-expression must evaluate to an exception type or a tuple of exception types.
+expression must evaluate to an exception type or a tuple of exception types. Parentheses
+can be dropped if multiple exception types are provided and the ``as`` clause is not used.
 The raised exception matches an :keyword:`!except` clause whose expression evaluates
 to the class or a :term:`non-virtual base class <abstract base class>` of the exception object,
 or to a tuple that contains such a class.

Doc/whatsnew/3.14.rst

@@ -90,6 +90,33 @@ If you encounter :exc:`NameError`\s or pickling errors coming out of
 New features
 ============
 
+.. _whatsnew314-pep758:
+
+PEP 758 – Allow except and except* expressions without parentheses
+------------------------------------------------------------------
+
+The :keyword:`except` and :keyword:`except* <except_star>` expressions now allow
+parentheses to be omitted when there are multiple exception types and the ``as`` clause is not used.
+For example the following expressions are now valid:
+
+.. code-block:: python
+
+   try:
+       release_new_sleep_token_album()
+   except AlbumNotFound, SongsTooGoodToBeReleased:
+       print("Sorry, no new album this year.")
+
+    # The same applies to except* (for exception groups):
+   try:
+       release_new_sleep_token_album()
+   except* AlbumNotFound, SongsTooGoodToBeReleased:
+       print("Sorry, no new album this year.")
+
+Check :pep:`758` for more details.
+
+(Contributed by Pablo Galindo and Brett Cannon in :gh:`131831`.)
+
+
 .. _whatsnew314-pep649:
 
 PEP 649: deferred evaluation of annotations
@@ -679,6 +706,13 @@ json
   (Contributed by Trey Hunner in :gh:`122873`.)
 
 
+linecache
+---------
+
+* :func:`linecache.getline` can retrieve source code for frozen modules.
+  (Contributed by Tian Gao in :gh:`131638`.)
+
+
 mimetypes
 ---------
 

Grammar/python.gram

@@ -435,14 +435,18 @@ try_stmt[stmt_ty]:
 
 except_block[excepthandler_ty]:
     | invalid_except_stmt_indent
-    | 'except' e=expression t=['as' z=NAME { z }] ':' b=block {
-        _PyAST_ExceptHandler(e, (t) ? ((expr_ty) t)->v.Name.id : NULL, b, EXTRA) }
+    | 'except' e=expressions ':' b=block {
+        _PyAST_ExceptHandler(e,  NULL, b, EXTRA) }
+    | 'except' e=expression 'as' t=NAME  ':' b=block {
+        _PyAST_ExceptHandler(e, ((expr_ty) t)->v.Name.id, b, EXTRA) }
     | 'except' ':' b=block { _PyAST_ExceptHandler(NULL, NULL, b, EXTRA) }
     | invalid_except_stmt
 except_star_block[excepthandler_ty]:
     | invalid_except_star_stmt_indent
-    | 'except' '*' e=expression t=['as' z=NAME { z }] ':' b=block {
-        _PyAST_ExceptHandler(e, (t) ? ((expr_ty) t)->v.Name.id : NULL, b, EXTRA) }
+    | 'except' '*' e=expressions ':' b=block {
+        _PyAST_ExceptHandler(e, NULL, b, EXTRA) }
+    | 'except' '*' e=expression 'as' t=NAME ':' b=block {
+        _PyAST_ExceptHandler(e, ((expr_ty) t)->v.Name.id, b, EXTRA) }
     | invalid_except_star_stmt
 finally_block[asdl_stmt_seq*]:
     | invalid_finally_stmt
@@ -1356,16 +1360,16 @@ invalid_try_stmt:
     | 'try' ':' block* except_star_block+ a='except' [expression ['as' NAME]] ':' {
         RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "cannot have both 'except' and 'except*' on the same 'try'") }
 invalid_except_stmt:
-    | 'except' a=expression ',' expressions ['as' NAME ] ':' {
-        RAISE_SYNTAX_ERROR_STARTING_FROM(a, "multiple exception types must be parenthesized") }
+    | 'except' a=expression ',' expressions 'as' NAME  ':' {
+        RAISE_SYNTAX_ERROR_STARTING_FROM(a, "multiple exception types must be parenthesized when using 'as'") }
     | a='except' expression ['as' NAME ] NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }
     | a='except' NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }
     | 'except' expression 'as' a=expression {
         RAISE_SYNTAX_ERROR_KNOWN_LOCATION(
             a, "cannot use except statement with %s", _PyPegen_get_expr_name(a)) }
 invalid_except_star_stmt:
-    | 'except' '*' a=expression ',' expressions ['as' NAME ] ':' {
-        RAISE_SYNTAX_ERROR_STARTING_FROM(a, "multiple exception types must be parenthesized") }
+    | 'except' '*' a=expression ',' expressions 'as' NAME  ':' {
+        RAISE_SYNTAX_ERROR_STARTING_FROM(a, "multiple exception types must be parenthesized when using 'as'") }
     | a='except' '*' expression ['as' NAME ] NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }
     | a='except' '*' (NEWLINE | ':') { RAISE_SYNTAX_ERROR("expected one or more exception types") }
     | 'except' '*' expression 'as' a=expression {

Include/internal/pycore_frame.h

@@ -28,6 +28,12 @@ struct _frame {
        PyEval_GetLocals requires a borrowed reference so the actual reference
        is stored here */
     PyObject *f_locals_cache;
+    /* A tuple containing strong references to fast locals that were overwritten
+     * via f_locals. Borrowed references to these locals may exist in frames
+     * closer to the top of the stack. The references in this tuple act as
+     * "support" for the borrowed references, ensuring that they remain valid.
+     */
+    PyObject *f_overwritten_fast_locals;
     /* The frame data, if this frame object owns the frame */
     PyObject *_f_frame_data[1];
 };

Include/internal/pycore_magic_number.h

@@ -273,6 +273,7 @@ Known values:
     Python 3.14a6 3618 (Add oparg to END_ASYNC_FOR)
     Python 3.14a6 3619 (Renumber RESUME opcode from 149 to 128)
     Python 3.14a6 3620 (Optimize bytecode for all/any/tuple called on a genexp)
+    Python 3.14a7 3621 (Optimize LOAD_FAST opcodes into LOAD_FAST_BORROW)
 
     Python 3.15 will start with 3650
 
@@ -285,7 +286,7 @@ PC/launcher.c must also be updated.
 
 */
 
-#define PYC_MAGIC_NUMBER 3620
+#define PYC_MAGIC_NUMBER 3621
 /* This is equivalent to converting PYC_MAGIC_NUMBER to 2 bytes
    (little-endian) and then appending b'\r\n'. */
 #define PYC_MAGIC_NUMBER_TOKEN \