Dev/sccache (#415)

- Use sccache: https://github.com/mozilla/sccache to speed up CI
- Not huge benefits for Windows but mac and linux really improves

.github/workflows/build_wheel.yml

@@ -19,13 +19,51 @@ jobs:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
 
+    env:
+      # Job level so that the build and the statistics step talk to the same
+      # sccache server configured for the GitHub Actions cache
+      SCCACHE_GHA_ENABLED: "true"
+
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
 
+      - uses: mozilla-actions/sccache-action@v0.0.11
+        with:
+          version: "v0.18.0"
+
+      # Without an MSVC environment scikit-build-core falls back to the Visual
+      # Studio generator on Windows, and MSBuild ignores the compiler launcher
+      - uses: TheMrMilchmann/setup-msvc-dev@v4.1.0
+        if: runner.os == 'Windows'
+        with:
+          arch: x64
+
+      # Linux wheels build inside a manylinux container, which needs its own
+      # sccache binary and the cache credentials the action exported; its
+      # statistics are printed after each wheel since the host cannot see them.
       - name: Build wheels
-        run: pipx run cibuildwheel==3.4.0
+        env:
+          CIBW_ENVIRONMENT_WINDOWS: CMAKE_GENERATOR=Ninja
+          CIBW_REPAIR_WHEEL_COMMAND_LINUX: >-
+            auditwheel repair -w {dest_dir} {wheel} && sccache --show-stats
+          CIBW_CONFIG_SETTINGS: >-
+            cmake.define.CMAKE_C_COMPILER_LAUNCHER=sccache
+            cmake.define.CMAKE_CXX_COMPILER_LAUNCHER=sccache
+            cmake.define.CMAKE_DISABLE_PRECOMPILE_HEADERS=ON
+          CIBW_ENVIRONMENT_PASS_LINUX: >-
+            SCCACHE_GHA_ENABLED ACTIONS_RESULTS_URL ACTIONS_RUNTIME_TOKEN
+            ACTIONS_CACHE_SERVICE_V2
+          CIBW_BEFORE_ALL_LINUX: >-
+            curl -sSL https://github.com/mozilla/sccache/releases/download/v0.18.0/sccache-v0.18.0-x86_64-unknown-linux-musl.tar.gz
+            | tar -xz -C /usr/local/bin --strip-components=1 --wildcards '*/sccache'
+            && chmod +x /usr/local/bin/sccache
+        run: pipx run cibuildwheel==4.3.0
 
-      - uses: actions/upload-artifact@v4
+      - name: Compiler cache statistics
+        if: runner.os != 'Linux'
+        run: sccache --show-stats
+
+      - uses: actions/upload-artifact@v7
         with:
           name: cibw-wheels-${{ matrix.os }}-${{ strategy.job-index }}
           path: ./wheelhouse/*.whl
@@ -34,12 +72,12 @@ jobs:
     name: Build source distribution
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
 
     - name: Build sdist
       run: pipx run build --sdist
 
-    - uses: actions/upload-artifact@v4
+    - uses: actions/upload-artifact@v7
       with:
         name: cibw-sdist
         path: dist/*.tar.gz
@@ -54,7 +92,7 @@ jobs:
     # or, alternatively, upload to PyPI on every tag starting with 'v' (remove on: release above to use this)
     # if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
     steps:
-        - uses: actions/download-artifact@v4
+        - uses: actions/download-artifact@v8
           with:
             # unpacks all CIBW artifacts into dist/
             pattern: cibw-*

.github/workflows/build_windows.yml

@@ -9,25 +9,42 @@ jobs:
   build:
     runs-on: windows-latest
 
+    env:
+      # sccache keeps compiled objects in the GitHub Actions cache, so later
+      # runs only recompile the translation units a change affects
+      SCCACHE_GHA_ENABLED: "true"
+
     steps:
       - uses: actions/checkout@v6
 
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v7
         with:
           python-version: "3.12"
 
       - name: Install Python dependencies
         run: python -m pip install ninja numpy matplotlib pytest pytest-check boost-histogram
 
-      # Puts cl.exe on the path so that CMake can use the Ninja generator
-      - uses: ilammy/msvc-dev-cmd@v1
+      # Puts cl.exe on the path so that CMake can use the Ninja generator.
+      # Pinned to a release tag: the v4 ref of this action is a branch.
+      - uses: TheMrMilchmann/setup-msvc-dev@v4.1.0
+        with:
+          arch: x64
 
+      - uses: mozilla-actions/sccache-action@v0.0.11
+        with:
+          version: "v0.18.0"
+
+      # Precompiled headers are disabled: sccache cannot cache MSVC
+      # compilations that use one
       - name: Configure
-        run: cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DAARE_TESTS=ON -DAARE_PYTHON_BINDINGS=ON -DAARE_WARNINGS_AS_ERRORS=ON
+        run: cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DAARE_TESTS=ON -DAARE_PYTHON_BINDINGS=ON -DAARE_WARNINGS_AS_ERRORS=ON -DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache -DCMAKE_DISABLE_PRECOMPILE_HEADERS=ON
 
       - name: Build
         run: cmake --build build
 
+      - name: Compiler cache statistics
+        run: sccache --show-stats
+
       - name: C++ unit tests
         run: ctest --test-dir build --output-on-failure -j4
 

.github/workflows/build_with_docs.yml

@@ -27,15 +27,19 @@ jobs:
 
     runs-on: ${{ matrix.platform }}
 
+    env:
+      # sccache keeps compiled objects in the GitHub Actions cache
+      SCCACHE_GHA_ENABLED: "true"
+
     defaults:
       run:
         shell: "bash -l {0}"
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
 
       - name: Get conda
-        uses: conda-incubator/setup-miniconda@v3
+        uses: conda-incubator/setup-miniconda@v4
         with:
           python-version: ${{ matrix.python-version }}
           environment-file: etc/dev-env.yml
@@ -43,14 +47,23 @@ jobs:
           channels: conda-forge
           conda-remove-defaults: "true"
 
+      - uses: mozilla-actions/sccache-action@v0.0.11
+        with:
+          version: "v0.18.0"
+
+      # Precompiled headers are disabled because sccache does not cache
+      # compilations that use one
       - name: Build library and docs
         run: |
             mkdir build 
             cd build 
-            cmake .. -DCMAKE_BUILD_TYPE=${{env.BUILD_TYPE}} -DAARE_SYSTEM_LIBRARIES=ON -DAARE_PYTHON_BINDINGS=ON -DAARE_DOCS=ON -DAARE_TESTS=ON -DAARE_WARNINGS_AS_ERRORS=ON
+            cmake .. -DCMAKE_BUILD_TYPE=${{env.BUILD_TYPE}} -DAARE_SYSTEM_LIBRARIES=ON -DAARE_PYTHON_BINDINGS=ON -DAARE_DOCS=ON -DAARE_TESTS=ON -DAARE_WARNINGS_AS_ERRORS=ON -DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache -DCMAKE_DISABLE_PRECOMPILE_HEADERS=ON
             make -j 4 
             make docs
 
+      - name: Compiler cache statistics
+        run: sccache --show-stats
+
       - name: C++ unit tests
         working-directory: ${{github.workspace}}/build
         run: ctest -C ${{env.BUILD_TYPE}} -j4
@@ -63,7 +76,7 @@ jobs:
       - name: Upload static files as artifact
         if: matrix.platform == 'ubuntu-latest'
         id: deployment
-        uses: actions/upload-pages-artifact@v3 
+        uses: actions/upload-pages-artifact@v5 
         with:
          path: build/docs/html/
   deploy:
@@ -76,7 +89,7 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5
 
 
 

conda-recipe/meta.yaml

@@ -26,7 +26,7 @@ requirements:
     - python
     - pip
     - numpy >=2.1
-    - scikit-build-core >=0.11
+    - scikit-build-core >=1.0
     - pybind11 >=3.0.3
     - matplotlib # needed in host to solve the environment for run
 

pyproject.toml

@@ -1,11 +1,12 @@
-[tool.scikit-build.metadata.version]
+[[tool.dynamic-metadata]]
+field = "version"
 provider = "scikit_build_core.metadata.regex"
 input = "VERSION"
 regex = '^(?P<version>\d+(?:\.\d+)*(?:[\.\+\w]+)?)$'
-result = "{version}" 
+result = "{version}"
 
 [build-system]
-requires = ["scikit-build-core>=0.11", "pybind11", "numpy"]
+requires = ["scikit-build-core>=1.0", "pybind11", "numpy"]
 build-backend = "scikit_build_core.build"
 
 [project]
@@ -34,6 +35,9 @@ build = "cp{312,313,314}-win_amd64"
 
 [tool.scikit-build]
 build.verbose = true
+# A fixed build directory keeps the absolute paths of the compiled sources
+# stable between runs, which sccache needs for a cache hit
+build-dir = "build/{wheel_tag}"
 cmake.build-type = "Release"
 install.components = ["python"]