ci: Add macOS and Windows build jobs.

.github/workflows/build.yml

@@ -10,30 +10,32 @@ jobs:
   build:
     strategy:
       matrix:
-        os: [ubuntu-20.04]
+        os: [ubuntu-22.04, macos-13, windows-2022]
       fail-fast: false
     runs-on: ${{ matrix.os }}
     name: build.py ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v3
         with:
           submodules: true
-      - name: Install toolchain (Ubuntu)
-        if: runner.os == 'Linux'
-        run: |
-          sudo apt-get install -y gcc-arm-none-eabi libnewlib-arm-none-eabi
-          sudo apt-get install -y cmake
+      - name: Setup arm-none-eabi-gcc v10.3
+        uses: carlosperate/arm-none-eabi-gcc-action@v1
+        with:
+          release: 10.3-2021.10
+      - name: Install CMake v3.22 & Ninja via PyPI
+        run: python -m pip install cmake==3.28.3 ninja==1.11.1.1
       - name: Check Versions
         run: |
           arm-none-eabi-gcc --version
           cmake --version
+          ninja --version
       - name: Build
         run: |
           make -C lib/micropython/mpy-cross -j2
           cd src
-          make -j2
+          BUILD_VERBOSE=1 make -j2
       - name: Upload hex file
         uses: actions/upload-artifact@v3
         with:
-          name: MICROBIT-MICROPYTHON-${{ github.sha }}.hex
+          name: MICROBIT-MICROPYTHON-${{ github.sha }}-${{ matrix.os }}.hex
           path: src/MICROBIT.hex