Merge branch 'main' into update-patchcheck-remote-behavior

Author: kattni

.github/CODEOWNERS

@@ -35,6 +35,7 @@ Objects/type*                 @markshannon
 Objects/codeobject.c          @markshannon
 Objects/frameobject.c         @markshannon
 Objects/call.c                @markshannon
+Objects/object.c              @ZeroIntensity
 Python/ceval*.c               @markshannon
 Python/ceval*.h               @markshannon
 Python/codegen.c              @markshannon @iritkatriel
@@ -44,8 +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
@@ -66,8 +68,8 @@ Doc/_static/**                @AA-Turner @hugovk
 Doc/tools/**                  @AA-Turner @hugovk
 
 # runtime state/lifecycle
-**/*pylifecycle*              @ericsnowcurrently
-**/*pystate*                  @ericsnowcurrently
+**/*pylifecycle*              @ericsnowcurrently @ZeroIntensity
+**/*pystate*                  @ericsnowcurrently @ZeroIntensity
 **/*preconfig*                @ericsnowcurrently
 **/*initconfig*               @ericsnowcurrently
 **/*pathconfig*               @ericsnowcurrently
@@ -187,13 +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
@@ -340,3 +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/ccache-action@v1.2
+      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/exceptions.rst

@@ -749,6 +749,16 @@ Exception Classes
    .. versionadded:: 3.2
 
 
+.. c:function:: int PyExceptionClass_Check(PyObject *ob)
+
+   Return non-zero if *ob* is an exception class, zero otherwise. This function always succeeds.
+
+
+.. c:function:: const char *PyExceptionClass_Name(PyObject *ob)
+
+   Return :c:member:`~PyTypeObject.tp_name` of the exception class *ob*.
+
+
 Exception Objects
 =================
 

Doc/c-api/extension-modules.rst

@@ -242,6 +242,6 @@ in the following ways:
 * Single-phase modules support module lookup functions like
   :c:func:`PyState_FindModule`.
 
-.. [#testsinglephase] ``_testsinglephase`` is an internal module used \
-   in CPython's self-test suite; your installation may or may not \
+.. [#testsinglephase] ``_testsinglephase`` is an internal module used
+   in CPython's self-test suite; your installation may or may not
    include it.

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/conf.py

@@ -79,6 +79,10 @@
 rst_epilog = f"""
 .. |python_version_literal| replace:: ``Python {version}``
 .. |python_x_dot_y_literal| replace:: ``python{version}``
+.. |python_x_dot_y_t_literal| replace:: ``python{version}t``
+.. |python_x_dot_y_t_literal_config| replace:: ``python{version}t-config``
+.. |x_dot_y_b2_literal| replace:: ``{version}.0b2``
+.. |applications_python_version_literal| replace:: ``/Applications/Python {version}/``
 .. |usr_local_bin_python_x_dot_y_literal| replace:: ``/usr/local/bin/python{version}``
 
 .. Apparently this how you hack together a formatted link:

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/free-threading-extensions.rst

@@ -6,8 +6,8 @@
 C API Extension Support for Free Threading
 ******************************************
 
-Starting with the 3.13 release, CPython has experimental support for running
-with the :term:`global interpreter lock` (GIL) disabled in a configuration
+Starting with the 3.13 release, CPython has support for running with
+the :term:`global interpreter lock` (GIL) disabled in a configuration
 called :term:`free threading`.  This document describes how to adapt C API
 extensions to support free threading.