feat: cross-compile support for macOS x64, Linux arm64, Windows arm64

Add CLICE_TARGET_TRIPLE to toolchain.cmake for cross-compilation.
Upgrade LLVM from 21.1.4 to 21.1.8 and switch publish workflow
from xmake to CMake.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 16bit-ykiko

.github/workflows/build-llvm.yml

@@ -12,6 +12,7 @@ jobs:
       fail-fast: false
       matrix:
         include:
+          # ── Native builds ──────────────────────────────────────────────
           - os: windows-2025
             llvm_mode: Debug
             lto: OFF
@@ -39,6 +40,38 @@ jobs:
           - os: macos-15
             llvm_mode: RelWithDebInfo
             lto: ON
+
+          # ── Cross-compilation builds ───────────────────────────────────
+          # macOS x64 (from arm64 macos-15)
+          - os: macos-15
+            llvm_mode: RelWithDebInfo
+            lto: OFF
+            target_triple: x86_64-apple-darwin
+          - os: macos-15
+            llvm_mode: RelWithDebInfo
+            lto: ON
+            target_triple: x86_64-apple-darwin
+
+          # Linux aarch64 (from x64 ubuntu-24.04)
+          - os: ubuntu-24.04
+            llvm_mode: RelWithDebInfo
+            lto: OFF
+            target_triple: aarch64-linux-gnu
+          - os: ubuntu-24.04
+            llvm_mode: RelWithDebInfo
+            lto: ON
+            target_triple: aarch64-linux-gnu
+
+          # Windows arm64 (from x64 windows-2025)
+          - os: windows-2025
+            llvm_mode: RelWithDebInfo
+            lto: OFF
+            target_triple: aarch64-pc-windows-msvc
+          - os: windows-2025
+            llvm_mode: RelWithDebInfo
+            lto: ON
+            target_triple: aarch64-pc-windows-msvc
+
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout repository
@@ -76,17 +109,27 @@ jobs:
           cache: true
           locked: true
 
-      - name: Clone llvm-project (21.1.4)
+      - name: Clone llvm-project (21.1.8)
         shell: bash
         run: |
-          git clone --branch llvmorg-21.1.4 --depth 1 https://github.com/llvm/llvm-project.git .llvm
+          git clone --branch llvmorg-21.1.8 --depth 1 https://github.com/llvm/llvm-project.git .llvm
 
       - name: Build LLVM (install-distribution)
         shell: bash
         run: |
-          pixi run build-llvm --llvm-src=.llvm --mode="${{ matrix.llvm_mode }}" --lto="${{ matrix.lto }}" --build-dir=build
+          EXTRA_ARGS=""
+          if [[ -n "${{ matrix.target_triple }}" ]]; then
+            EXTRA_ARGS="--target-triple=${{ matrix.target_triple }}"
+          fi
+          pixi run build-llvm \
+            --llvm-src=.llvm \
+            --mode="${{ matrix.llvm_mode }}" \
+            --lto="${{ matrix.lto }}" \
+            --build-dir=build \
+            ${EXTRA_ARGS}
 
       - name: Build clice using installed LLVM
+        if: ${{ !matrix.target_triple }}
         shell: bash
         run: |
           cmake -B build -G Ninja \
@@ -99,6 +142,7 @@ jobs:
           cmake --build build
 
       - name: Run tests
+        if: ${{ !matrix.target_triple }}
         shell: bash
         run: |
           EXE_EXT=""
@@ -108,8 +152,10 @@ jobs:
           ./build/bin/unit_tests${EXE_EXT} --test-dir="./tests/data"
           uv run --project tests pytest -s --log-cli-level=INFO tests/integration --executable=./build/bin/clice${EXE_EXT}
 
+      # Prune is only supported for native builds (requires linking clice to test).
+      # Cross-compiled targets reuse the native prune manifest of the same OS.
       - name: Prune LLVM static libraries (Debug/RelWithDebInfo no LTO)
-        if: matrix.llvm_mode == 'Debug' || (matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'OFF')
+        if: (!matrix.target_triple) && (matrix.llvm_mode == 'Debug' || (matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'OFF'))
         shell: bash
         run: |
           MANIFEST="pruned-libs-${{ matrix.os }}.json"
@@ -123,16 +169,36 @@ jobs:
             --manifest "${MANIFEST}"
 
       - name: Upload pruned-libs manifest
-        if: matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'OFF'
+        if: (!matrix.target_triple) && matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'OFF'
         uses: actions/upload-artifact@v4
         with:
           name: llvm-pruned-libs-${{ matrix.os }}
           path: ${{ env.LLVM_PRUNED_MANIFEST }}
           if-no-files-found: error
           compression-level: 0
 
-      - name: Apply pruned-libs manifest (RelWithDebInfo + LTO)
-        if: matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'ON'
+      - name: Apply pruned-libs manifest (RelWithDebInfo + LTO, native only)
+        if: (!matrix.target_triple) && matrix.llvm_mode == 'RelWithDebInfo' && matrix.lto == 'ON'
+        shell: bash
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          MANIFEST="pruned-libs-${{ matrix.os }}.json"
+          python3 scripts/prune-llvm-bin.py \
+            --action apply \
+            --manifest "${MANIFEST}" \
+            --install-dir ".llvm/build-install/lib" \
+            --build-dir "build" \
+            --gh-run-id "${{ github.run_id }}" \
+            --gh-artifact "llvm-pruned-libs-${{ matrix.os }}" \
+            --gh-download-dir "artifacts" \
+            --max-attempts 60 \
+            --sleep-seconds 60
+
+      # For cross-compiled LTO builds, apply the native prune manifest.
+      # The unused library set is arch-independent (same API surface).
+      - name: Apply pruned-libs manifest (cross-compile + LTO)
+        if: matrix.target_triple && matrix.lto == 'ON'
         shell: bash
         env:
           GH_TOKEN: ${{ github.token }}
@@ -157,16 +223,28 @@ jobs:
             MODE_TAG="debug"
           fi
 
-          ARCH="x64"
-          PLATFORM="linux"
-          TOOLCHAIN="gnu"
-          if [[ "${{ matrix.os }}" == windows-* ]]; then
-            PLATFORM="windows"
-            TOOLCHAIN="msvc"
-          elif [[ "${{ matrix.os }}" == macos-* ]]; then
-            ARCH="arm64"
-            PLATFORM="macos"
-            TOOLCHAIN="clang"
+          # Determine arch/platform/toolchain from target triple or runner OS
+          if [[ -n "${{ matrix.target_triple }}" ]]; then
+            case "${{ matrix.target_triple }}" in
+              x86_64-apple-darwin)
+                ARCH="x64"; PLATFORM="macos"; TOOLCHAIN="clang" ;;
+              aarch64-linux-gnu)
+                ARCH="aarch64"; PLATFORM="linux"; TOOLCHAIN="gnu" ;;
+              aarch64-pc-windows-msvc)
+                ARCH="aarch64"; PLATFORM="windows"; TOOLCHAIN="msvc" ;;
+            esac
+          else
+            ARCH="x64"
+            PLATFORM="linux"
+            TOOLCHAIN="gnu"
+            if [[ "${{ matrix.os }}" == windows-* ]]; then
+              PLATFORM="windows"
+              TOOLCHAIN="msvc"
+            elif [[ "${{ matrix.os }}" == macos-* ]]; then
+              ARCH="arm64"
+              PLATFORM="macos"
+              TOOLCHAIN="clang"
+            fi
           fi
 
           SUFFIX=""

.github/workflows/publish-clice.yml

@@ -9,61 +9,65 @@ jobs:
       fail-fast: false
       matrix:
         include:
+          # ── Native builds ──────────────────────────────────────────────
           - os: windows-2025
-            artifact_name: clice.zip
             asset_name: clice-x64-windows-msvc.zip
-            symbol_artifact_name: clice-symbol.zip
             symbol_asset_name: clice-x64-windows-msvc-symbol.zip
 
           - os: ubuntu-24.04
-            artifact_name: clice.tar.gz
             asset_name: clice-x86_64-linux-gnu.tar.gz
-            symbol_artifact_name: clice-symbol.tar.gz
             symbol_asset_name: clice-x86_64-linux-gnu-symbol.tar.gz
 
           - os: macos-15
-            artifact_name: clice.tar.gz
             asset_name: clice-arm64-macos-darwin.tar.gz
-            symbol_artifact_name: clice-symbol.tar.gz
             symbol_asset_name: clice-arm64-macos-darwin-symbol.tar.gz
 
+          # ── Cross-compilation builds ───────────────────────────────────
+          - os: macos-15
+            target_triple: x86_64-apple-darwin
+            asset_name: clice-x86_64-macos-darwin.tar.gz
+            symbol_asset_name: clice-x86_64-macos-darwin-symbol.tar.gz
+
+          - os: ubuntu-24.04
+            target_triple: aarch64-linux-gnu
+            asset_name: clice-aarch64-linux-gnu.tar.gz
+            symbol_asset_name: clice-aarch64-linux-gnu-symbol.tar.gz
+
+          - os: windows-2025
+            target_triple: aarch64-pc-windows-msvc
+            asset_name: clice-aarch64-windows-msvc.zip
+            symbol_asset_name: clice-aarch64-windows-msvc-symbol.zip
+
     runs-on: ${{ matrix.os }}
 
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Setup xmake
-        uses: xmake-io/github-action-setup-xmake@v1
-        with:
-          xmake-version: 3.0.5
-          actions-cache-folder: ".xmake-cache"
-          actions-cache-key: ${{ matrix.os }}
-          package-cache: true
-          package-cache-key: ${{ matrix.os }}-pkg-release-v1
-          build-cache: true
-          build-cache-key: ${{ matrix.os }}-build-release-v1
-
       - uses: ./.github/actions/setup-pixi
         with:
           environments: package
 
-      - name: Remove ci llvm toolchain on Windows
-        if: runner.os == 'Windows'
+      - name: Build & Package
+        shell: bash
         run: |
-          # @see https://github.com/xmake-io/xmake/issues/7158
-          xmake lua os.rmdir "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Tools/Llvm"
-          xmake lua os.rmdir "C:/Program Files/LLVM"
-
-      - name: Package
-        run: pixi run package
+          EXTRA_ARGS=""
+          if [[ -n "${{ matrix.target_triple }}" ]]; then
+            EXTRA_ARGS="-DCLICE_TARGET_TRIPLE=${{ matrix.target_triple }}"
+          fi
+          cmake -B build/release -G Ninja \
+            -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+            -DCMAKE_TOOLCHAIN_FILE=cmake/toolchain.cmake \
+            -DCLICE_RELEASE=ON \
+            ${EXTRA_ARGS}
+          cmake --build build/release
 
       - name: Upload Main Package to Release
         if: startsWith(github.ref, 'refs/tags/v')
         uses: svenstaro/upload-release-action@v2
         with:
           repo_token: ${{ secrets.GITHUB_TOKEN }}
-          file: build/xpack/clice/${{ matrix.artifact_name }}
+          file: build/release/clice${{ contains(matrix.asset_name, '.zip') && '.zip' || '.tar.gz' }}
           asset_name: ${{ matrix.asset_name }}
           tag: ${{ github.ref }}
           overwrite: true
@@ -73,7 +77,7 @@ jobs:
         uses: svenstaro/upload-release-action@v2
         with:
           repo_token: ${{ secrets.GITHUB_TOKEN }}
-          file: build/xpack/clice/${{ matrix.symbol_artifact_name }}
+          file: build/release/clice-symbol${{ contains(matrix.asset_name, '.zip') && '.zip' || '.tar.gz' }}
           asset_name: ${{ matrix.symbol_asset_name }}
           tag: ${{ github.ref }}
           overwrite: true

cmake/llvm.cmake

@@ -25,6 +25,16 @@ function(setup_llvm LLVM_VERSION)
         list(APPEND LLVM_SETUP_ARGS "--offline")
     endif()
 
+    if(DEFINED CLICE_TARGET_TRIPLE)
+        if(CLICE_TARGET_TRIPLE MATCHES "linux")
+            list(APPEND LLVM_SETUP_ARGS "--target-platform" "Linux")
+        elseif(CLICE_TARGET_TRIPLE MATCHES "darwin")
+            list(APPEND LLVM_SETUP_ARGS "--target-platform" "macosx")
+        elseif(CLICE_TARGET_TRIPLE MATCHES "windows")
+            list(APPEND LLVM_SETUP_ARGS "--target-platform" "Windows")
+        endif()
+    endif()
+
     execute_process(
         COMMAND "${Python3_EXECUTABLE}" "${LLVM_SETUP_SCRIPT}" ${LLVM_SETUP_ARGS}
         RESULT_VARIABLE LLVM_SETUP_RESULT

cmake/package.cmake

@@ -1,7 +1,7 @@
 include_guard()
 
 include(${CMAKE_CURRENT_LIST_DIR}/llvm.cmake)
-setup_llvm("21.1.4+r1")
+setup_llvm("21.1.8")
 
 # install dependencies
 include(FetchContent)

cmake/toolchain.cmake

@@ -1,5 +1,29 @@
 cmake_minimum_required(VERSION 3.30)
 
+# Cross-compilation support via CLICE_TARGET_TRIPLE.
+# Examples:
+#   -DCLICE_TARGET_TRIPLE=x86_64-apple-darwin      (macOS x64 from arm64)
+#   -DCLICE_TARGET_TRIPLE=aarch64-linux-gnu         (Linux arm64 from x64)
+#   -DCLICE_TARGET_TRIPLE=aarch64-pc-windows-msvc   (Windows arm64 from x64)
+if(DEFINED CLICE_TARGET_TRIPLE)
+    if(CLICE_TARGET_TRIPLE MATCHES "^x86_64-apple-darwin")
+        set(CMAKE_OSX_ARCHITECTURES "x86_64" CACHE STRING "")
+    elseif(CLICE_TARGET_TRIPLE MATCHES "^aarch64-.*-linux")
+        set(CMAKE_SYSTEM_NAME Linux)
+        set(CMAKE_SYSTEM_PROCESSOR aarch64)
+        set(CMAKE_C_COMPILER_TARGET "aarch64-linux-gnu" CACHE STRING "")
+        set(CMAKE_CXX_COMPILER_TARGET "aarch64-linux-gnu" CACHE STRING "")
+        if(DEFINED ENV{CONDA_PREFIX} AND NOT DEFINED CMAKE_SYSROOT)
+            set(CMAKE_SYSROOT "$ENV{CONDA_PREFIX}/aarch64-conda-linux-gnu/sysroot" CACHE PATH "")
+        endif()
+    elseif(CLICE_TARGET_TRIPLE MATCHES "^aarch64-.*-windows")
+        set(CMAKE_SYSTEM_NAME Windows)
+        set(CMAKE_SYSTEM_PROCESSOR ARM64)
+        set(CMAKE_C_COMPILER_TARGET "aarch64-pc-windows-msvc" CACHE STRING "")
+        set(CMAKE_CXX_COMPILER_TARGET "aarch64-pc-windows-msvc" CACHE STRING "")
+    endif()
+endif()
+
 set(CMAKE_C_COMPILER clang CACHE STRING "")
 set(CMAKE_CXX_COMPILER clang++ CACHE STRING "")