.github/workflows/build_clang_tidy.yml

# Copyright 2026 The IREE Authors
#
# Licensed under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

# Builds clang-tidy from the bundled llvm-project and uploads it as an artifact.
# This workflow runs when the llvm-project submodule is updated on main.

name: Build clang-tidy

on:
  push:
    branches:
      - main
    paths:
      - 'third_party/llvm-project'
  workflow_dispatch:

permissions:
  contents: read

# Only run on iree-org/iree repository.
jobs:
  build_clang_tidy:
    if: github.repository == 'iree-org/iree'
    runs-on: azure-linux-scale
    container:
      image: ghcr.io/iree-org/cpubuilder_ubuntu_jammy@sha256:78a558b999b230f7e1da376639e14b44f095f30f1777d6a272ba48c0bbdd4ccb
    defaults:
      run:
        shell: bash
    env:
      BUILD_DIR: build
      SCCACHE_AZURE_CONNECTION_STRING: "${{ secrets.AZURE_CCACHE_CONNECTION_STRING }}"
      SCCACHE_AZURE_BLOB_CONTAINER: ccache-container
      SCCACHE_CACHE_ZSTD_LEVEL: 10
      SCCACHE_AZURE_KEY_PREFIX: "build_clang_tidy"
    steps:
      - name: "Checking out repository"
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          submodules: true

      - name: Install Python requirements
        run: python3 -m pip install -r ./build_tools/github_actions/ci_requirements.txt
      - name: "Setting up CMake"
        run: |
          source ./build_tools/cmake/setup_build.sh
          source ./build_tools/cmake/setup_sccache.sh

          CMAKE_ARGS=(
            "-G" "Ninja"
            "-B" "${BUILD_DIR}"
            "-DCMAKE_BUILD_TYPE=Release"

            # Use lld for faster linking.
            "-DIREE_ENABLE_LLD=ON"

            # Enable split dwarf and thin archives for faster linking.
            "-DIREE_ENABLE_SPLIT_DWARF=ON"
            "-DIREE_ENABLE_THIN_ARCHIVES=ON"

            # Enable clang-tools-extra to build clang-tidy.
            "-DIREE_BUILD_CLANG_TOOLS_EXTRA=ON"

            # Enable the llvm-cpu backend which sets up clang.
            "-DIREE_TARGET_BACKEND_LLVM_CPU=ON"

            # Disable backends and features we don't need.
            "-DIREE_TARGET_BACKEND_CUDA=OFF"
            "-DIREE_TARGET_BACKEND_ROCM=OFF"
            "-DIREE_TARGET_BACKEND_METAL_SPIRV=OFF"
            "-DIREE_TARGET_BACKEND_VULKAN_SPIRV=OFF"
            "-DIREE_TARGET_BACKEND_WEBGPU_SPIRV=OFF"
            "-DIREE_BUILD_TESTS=OFF"
            "-DIREE_BUILD_SAMPLES=OFF"
          )

          "$CMAKE_BIN" "${CMAKE_ARGS[@]}"

      - name: "Building clang-tidy"
        run: cmake --build "${BUILD_DIR}" --target clang-tidy -- -k 0

      - name: "Prepare artifact"
        run: |
          mkdir -p artifact
          cp "${BUILD_DIR}/llvm-project/bin/clang-tidy" artifact/clang-tidy
          # Include version information.
          cd third_party/llvm-project && git rev-parse HEAD > ../../artifact/llvm-project-revision.txt

      - name: "Upload clang-tidy artifact"
        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
        with:
          name: iree-clang-tidy-linux-x86_64
          path: artifact/
          retention-days: 90

      - name: "Show sccache stats"
        if: always()
        run: sccache --show-stats