Merge remote-tracking branch 'upstream/main' into pure

Author: Fidget-Spinner

.github/CODEOWNERS

@@ -45,8 +45,9 @@ Python/flowgraph.c            @markshannon @iritkatriel
 Python/instruction_sequence.c @iritkatriel
 Python/bytecodes.c            @markshannon
 Python/optimizer*.c           @markshannon
-Python/optimizer_analysis.c   @Fidget-Spinner
-Python/optimizer_bytecodes.c  @Fidget-Spinner
+Python/optimizer_analysis.c   @Fidget-Spinner @tomasr8
+Python/optimizer_bytecodes.c  @Fidget-Spinner @tomasr8
+Python/optimizer_symbols.c    @tomasr8
 Python/symtable.c             @JelleZijlstra @carljm
 Lib/_pyrepl/*                 @pablogsal @lysnikolaou @ambv
 Lib/test/test_patma.py        @brandtbucher
@@ -188,13 +189,13 @@ Include/internal/pycore_time.h  @pganssle @abalkin
 /Tools/cases_generator/        @markshannon
 
 # AST
-Python/ast.c                  @isidentical @JelleZijlstra @eclips4
-Python/ast_preprocess.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
+Python/ast.c                  @isidentical @JelleZijlstra @eclips4 @tomasr8
+Python/ast_preprocess.c       @isidentical @eclips4 @tomasr8
+Parser/asdl.py                @isidentical @JelleZijlstra @eclips4 @tomasr8
+Parser/asdl_c.py              @isidentical @JelleZijlstra @eclips4 @tomasr8
+Lib/ast.py                    @isidentical @JelleZijlstra @eclips4 @tomasr8
+Lib/_ast_unparse.py           @isidentical @JelleZijlstra @eclips4 @tomasr8
+Lib/test/test_ast/            @eclips4 @tomasr8
 
 # Mock
 /Lib/unittest/mock.py         @cjw296
@@ -341,3 +342,6 @@ Modules/_xxtestfuzz/          @ammaraskar
 Python/remote_debug.h         @pablogsal
 Python/remote_debugging.c     @pablogsal
 Modules/_remote_debugging_module.c @pablogsal @ambv @1st1
+
+# gettext
+**/*gettext*                  @tomasr8

.github/workflows/build.yml

@@ -527,6 +527,14 @@ jobs:
       config_hash: ${{ needs.build-context.outputs.config-hash }}
       free-threading: ${{ matrix.free-threading }}
 
+  build-ubsan:
+    name: Undefined behavior sanitizer
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
+    uses: ./.github/workflows/reusable-ubsan.yml
+    with:
+      config_hash: ${{ needs.build-context.outputs.config-hash }}
+
   cross-build-linux:
     name: Cross build Linux
     runs-on: ubuntu-latest

.github/workflows/reusable-ubsan.yml

@@ -0,0 +1,74 @@
+name: Reusable Undefined Behavior Sanitizer
+
+on:
+  workflow_call:
+    inputs:
+      config_hash:
+        required: true
+        type: string
+
+env:
+  FORCE_COLOR: 1
+
+jobs:
+  build-ubsan-reusable:
+    name: 'Undefined behavior sanitizer'
+    runs-on: ubuntu-24.04
+    timeout-minutes: 60
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        persist-credentials: false
+    - name: Runner image version
+      run: echo "IMAGE_OS_VERSION=${ImageOS}-${ImageVersion}" >> "$GITHUB_ENV"
+    - name: Restore config.cache
+      uses: actions/cache@v4
+      with:
+        path: config.cache
+        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ inputs.config_hash }}
+    - name: Install dependencies
+      run: |
+        sudo ./.github/workflows/posix-deps-apt.sh
+        # Install clang-20
+        wget https://apt.llvm.org/llvm.sh
+        chmod +x llvm.sh
+        sudo ./llvm.sh 20
+    - name: UBSAN option setup
+      run: |
+        echo "UBSAN_OPTIONS=halt_on_error=1:abort_on_error=1:print_summary=1:print_stacktrace=1" >> "$GITHUB_ENV"
+        echo "CC=clang" >> "$GITHUB_ENV"
+        echo "CXX=clang++" >> "$GITHUB_ENV"
+    - name: Add ccache to PATH
+      run: |
+        echo "PATH=/usr/lib/ccache:$PATH" >> "$GITHUB_ENV"
+    - name: Configure ccache action
+      uses: hendrikmuhs/[email protected]
+      with:
+        save: ${{ github.event_name == 'push' }}
+        max-size: "200M"
+    - name: Configure CPython
+      run: >-
+        ./configure
+        --config-cache
+        --with-undefined-behavior-sanitizer
+        --with-pydebug
+    - name: Set up UBSAN log after configuration
+      run: |
+        echo "UBSAN_OPTIONS=${UBSAN_OPTIONS}:log_path=${GITHUB_WORKSPACE}/ubsan_log" >> "$GITHUB_ENV"
+    - name: Build CPython
+      run: make -j4
+    - name: Display build info
+      run: make pythoninfo
+    - name: Tests
+      run: ./python -m test -j4
+    - name: Display UBSAN logs
+      if: always()
+      run: find "${GITHUB_WORKSPACE}" -name 'ubsan_log.*' | xargs head -n 1000
+    - name: Archive UBSAN logs
+      if: always()
+      uses: actions/upload-artifact@v4
+      with:
+        name: >-
+          ubsan-logs
+        path: ubsan_log.*
+        if-no-files-found: ignore

Doc/c-api/refcounting.rst

@@ -210,7 +210,7 @@ of Python objects.
 
         Py_SETREF(dst, src);
 
-   That arranges to set *dst* to *src* _before_ releasing the reference
+   That arranges to set *dst* to *src* *before* releasing the reference
    to the old value of *dst*, so that any code triggered as a side-effect
    of *dst* getting torn down no longer believes *dst* points
    to a valid object.

Doc/c-api/type.rst

@@ -282,6 +282,10 @@ Type Objects
    and other places where a method's defining class cannot be passed using the
    :c:type:`PyCMethod` calling convention.
 
+   The returned reference is :term:`borrowed <borrowed reference>` from *type*,
+   and will be valid as long as you hold a reference to *type*.
+   Do not release it with :c:func:`Py_DECREF` or similar.
+
    .. versionadded:: 3.11
 
 .. c:function:: int PyType_GetBaseByToken(PyTypeObject *type, void *token, PyTypeObject **result)

Doc/data/refcounts.dat

@@ -2385,6 +2385,10 @@ PyType_GetFlags:PyTypeObject*:type:0:
 PyType_GetName:PyObject*::+1:
 PyType_GetName:PyTypeObject*:type:0:
 
+PyType_GetModuleByDef:PyObject*::0:
+PyType_GetModuleByDef:PyTypeObject*:type:0:
+PyType_GetModuleByDef:PyModuleDef*:def::
+
 PyType_GetQualName:PyObject*::+1:
 PyType_GetQualName:PyTypeObject*:type:0:
 

Doc/howto/regex.rst

@@ -1016,7 +1016,9 @@ extension.  This regular expression matches ``foo.bar`` and
 Now, consider complicating the problem a bit; what if you want to match
 filenames where the extension is not ``bat``? Some incorrect attempts:
 
-``.*[.][^b].*$``  The first attempt above tries to exclude ``bat`` by requiring
+``.*[.][^b].*$``
+
+The first attempt above tries to exclude ``bat`` by requiring
 that the first character of the extension is not a ``b``.  This is wrong,
 because the pattern also doesn't match ``foo.bar``.
 
@@ -1043,7 +1045,9 @@ confusing.
 
 A negative lookahead cuts through all this confusion:
 
-``.*[.](?!bat$)[^.]*$``  The negative lookahead means: if the expression ``bat``
+``.*[.](?!bat$)[^.]*$``
+
+The negative lookahead means: if the expression ``bat``
 doesn't match at this point, try the rest of the pattern; if ``bat$`` does
 match, the whole pattern will fail.  The trailing ``$`` is required to ensure
 that something like ``sample.batch``, where the extension only starts with

Doc/library/concurrent.futures.rst

@@ -265,7 +265,7 @@ Each worker's interpreter is isolated from all the other interpreters.
 "Isolated" means each interpreter has its own runtime state and
 operates completely independently.  For example, if you redirect
 :data:`sys.stdout` in one interpreter, it will not be automatically
-redirected any other interpreter.  If you import a module in one
+redirected to any other interpreter.  If you import a module in one
 interpreter, it is not automatically imported in any other.  You
 would need to import the module separately in interpreter where
 you need it.  In fact, each module imported in an interpreter is
@@ -287,7 +287,7 @@ efficient alternative is to serialize with :mod:`pickle` and then send
 the bytes over a shared :mod:`socket <socket>` or
 :func:`pipe <os.pipe>`.
 
-.. class:: InterpreterPoolExecutor(max_workers=None, thread_name_prefix='', initializer=None, initargs=(), shared=None)
+.. class:: InterpreterPoolExecutor(max_workers=None, thread_name_prefix='', initializer=None, initargs=())
 
    A :class:`ThreadPoolExecutor` subclass that executes calls asynchronously
    using a pool of at most *max_workers* threads.  Each thread runs
@@ -304,32 +304,17 @@ the bytes over a shared :mod:`socket <socket>` or
    and *initargs* using :mod:`pickle` when sending them to the worker's
    interpreter.
 
-   .. note::
-      Functions defined in the ``__main__`` module cannot be pickled
-      and thus cannot be used.
-
    .. note::
       The executor may replace uncaught exceptions from *initializer*
       with :class:`~concurrent.futures.interpreter.ExecutionFailed`.
 
-   The optional *shared* argument is a :class:`dict` of objects that all
-   interpreters in the pool share.  The *shared* items are added to each
-   interpreter's ``__main__`` module.  Not all objects are shareable.
-   Shareable objects include the builtin singletons, :class:`str`
-   and :class:`bytes`, and :class:`memoryview`.  See :pep:`734`
-   for more info.
-
    Other caveats from parent :class:`ThreadPoolExecutor` apply here.
 
 :meth:`~Executor.submit` and :meth:`~Executor.map` work like normal,
 except the worker serializes the callable and arguments using
 :mod:`pickle` when sending them to its interpreter.  The worker
 likewise serializes the return value when sending it back.
 
-.. note::
-   Functions defined in the ``__main__`` module cannot be pickled
-   and thus cannot be used.
-
 When a worker's current task raises an uncaught exception, the worker
 always tries to preserve the exception as-is.  If that is successful
 then it also sets the ``__cause__`` to a corresponding

Doc/library/logging.config.rst

@@ -586,7 +586,7 @@ configuration dictionary for the handler named ``foo``, and later (once that
 handler has been configured) it points to the configured handler instance.
 Thus, ``cfg://handlers.foo`` could resolve to either a dictionary or a handler
 instance. In general, it is wise to name handlers in a way such that dependent
-handlers are configured _after_ any handlers they depend on; that allows
+handlers are configured *after* any handlers they depend on; that allows
 something like ``cfg://handlers.foo`` to be used in configuring a handler that
 depends on handler ``foo``. If that dependent handler were named ``bar``,
 problems would result, because the configuration of ``bar`` would be attempted

Doc/library/pkgutil.rst

@@ -69,8 +69,8 @@ support.
 
    Yield :term:`finder` objects for the given module name.
 
-   If fullname contains a ``'.'``, the finders will be for the package
-   containing fullname, otherwise they will be all registered top level
+   If *fullname* contains a ``'.'``, the finders will be for the package
+   containing *fullname*, otherwise they will be all registered top level
    finders (i.e. those on both :data:`sys.meta_path` and :data:`sys.path_hooks`).
 
    If the named module is in a package, that package is imported as a side