reusable-san.yml

name: Reusable Sanitizer

on:
  workflow_call:
    inputs:
      sanitizer:
        required: true
        type: string
      free-threading:
        description: Whether to use free-threaded mode
        required: false
        type: boolean
        default: false

permissions:
  contents: read

env:
  FORCE_COLOR: 1
  OPENSSL_VER: 3.5.9

jobs:
  build-san-reusable:
    name: >-
      ${{ inputs.sanitizer }}${{
        inputs.free-threading
        && ' (free-threading)'
        || ''
      }}
    runs-on: ubuntu-26.04
    timeout-minutes: 60
    steps:
    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
      with:
        persist-credentials: false
    - name: Runner image version
      run: echo "IMAGE_OS_VERSION=${ImageOS}-${ImageVersion}" >> "$GITHUB_ENV"
    - name: Install dependencies
      run: |
        sudo ./.github/workflows/posix-deps-apt.sh
        # On ubuntu-26.04 image, clang is clang-21 by default
        # NOTE: when bumping to a new version of clang,
        # please update the versions in `Tools/pixi-packages/variants.yaml` too.
        echo "CC=clang" >> "$GITHUB_ENV"
        echo "CXX=clang++" >> "$GITHUB_ENV"
    - name: TSan option setup
      if: inputs.sanitizer == 'TSan'
      run: |
        sudo sysctl -w vm.mmap_rnd_bits=28  # Reduce ASLR to avoid TSan crashing

        echo "MULTISSL_DIR=${GITHUB_WORKSPACE}/multissl" >> "$GITHUB_ENV"
        echo "OPENSSL_DIR=${GITHUB_WORKSPACE}/multissl/openssl/${OPENSSL_VER}" >> "$GITHUB_ENV"
        echo "TSAN_OPTIONS=${SAN_LOG_OPTION} suppressions=${GITHUB_WORKSPACE}/Tools/tsan/suppressions${SUPPRESSIONS_SUFFIX}.txt handle_segv=0" >> "$GITHUB_ENV"
      env:
        SAN_LOG_OPTION: log_path=${{ github.workspace }}/san_log
        SUPPRESSIONS_SUFFIX: >-
          ${{
            inputs.free-threading
            && '_free_threading'
            || ''
          }}
    - name: UBSan option setup
      if: inputs.sanitizer == 'UBSan'
      run: >-
        echo
        "UBSAN_OPTIONS=${SAN_LOG_OPTION}
        halt_on_error=1
        suppressions=${GITHUB_WORKSPACE}/Tools/ubsan/suppressions.txt"
        >> "$GITHUB_ENV"
      env:
        SAN_LOG_OPTION: log_path=${{ github.workspace }}/san_log
    - name: MSan option setup
      if: inputs.sanitizer == 'MSan'
      run: |
        sudo sysctl -w vm.mmap_rnd_bits=28  # Reduce ASLR to avoid MSan re-executing

        echo "MSAN_OPTIONS=${SAN_LOG_OPTION} allocator_may_return_null=1 handle_segv=0" >> "$GITHUB_ENV"
        # MSan reports false positives for memory initialized by libraries
        # that are not built with MSan, so disable modules that use them.
        # _remote_debugging links to libzstd directly, but we unpoision the memory.
        {
          echo '*disabled*'
          echo '_bz2 _ctypes _curses _curses_panel _dbm _decimal _gdbm _hashlib'
          echo '_lzma _sqlite3 _ssl _tkinter _uuid _zstd readline zlib'
        } > Modules/Setup.local
      env:
        SAN_LOG_OPTION: log_path=${{ github.workspace }}/san_log
    - name: Add ccache to PATH
      run: |
        echo "PATH=/usr/lib/ccache:$PATH" >> "$GITHUB_ENV"
    - name: 'Restore OpenSSL build (TSan)'
      id: cache-openssl
      if: inputs.sanitizer == 'TSan'
      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
      with:
        path: ./multissl/openssl/${{ env.OPENSSL_VER }}
        key: ${{ env.IMAGE_OS_VERSION }}-multissl-openssl-tsan-${{ env.OPENSSL_VER }}
    - name: Install OpenSSL (TSan)
      if: >-
        inputs.sanitizer == 'TSan'
        && steps.cache-openssl.outputs.cache-hit != 'true'
      run: >-
        python3 Tools/ssl/multissltests.py
        --steps=library
        --base-directory="${MULTISSL_DIR}"
        --openssl="${OPENSSL_VER}"
        --system=Linux
        --tsan
    # gh-157958: -O2 instead of the pydebug default -Og to avoid a clang 21
    # compile-time blowup on some interpreter files.
    # (https://github.com/llvm/llvm-project/issues/179695)
    # MSan uses --with-assertions instead of --with-pydebug because its
    # hooks on the Python memory allocators hide uninitialized reads.
    - name: Configure CPython
      run: >-
        ./configure
        --config-cache
        OPT="-O2 -g"
        ${{
          inputs.sanitizer == 'TSan'
          && '--with-thread-sanitizer'
          || inputs.sanitizer == 'MSan'
          && '--with-memory-sanitizer'
          || '--with-undefined-behavior-sanitizer --with-strict-overflow'
        }}
        ${{ inputs.sanitizer == 'MSan' && '--with-assertions' || '--with-pydebug' }}
        ${{ inputs.sanitizer == 'TSan' && '--with-openssl="$OPENSSL_DIR" --with-openssl-rpath=auto' || '' }}
        ${{ inputs.free-threading && '--disable-gil' || '' }}
    - name: Build CPython
      run: make -j4
    - name: Display build info
      run: make pythoninfo
    - name: Tests
      run: >-
        ./python -m test
        ${{ inputs.sanitizer == 'TSan' && '--tsan' || '' }}
        -j4 -W --timeout=900 --slowest
    - name: Parallel tests
      if: >-
        inputs.sanitizer == 'TSan'
        && inputs.free-threading
      run: ./python -m test --tsan-parallel --parallel-threads=4 -j4 -W --timeout=600 --slowest
    - name: Display logs
      if: always()
      run: find "${GITHUB_WORKSPACE}" -name 'san_log.*' | xargs head -n 1000
    - name: Archive logs
      if: always()
      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
      with:
        name: >-
          ${{ inputs.sanitizer }}-logs-${{
            inputs.free-threading
            && 'free-threading'
            || 'default'
          }}
        path: san_log.*
        if-no-files-found: ignore