build,win: add mingw-w64 CI configuration (#3885)

Co-authored-by: Nicolas Noble <pixel@nobis-crew.org>

.github/workflows/CI-win.yml

@@ -62,3 +62,61 @@ jobs:
         shell: cmd
         run:
           build\\RelWithDebInfo\\uv_run_tests_a.exe
+
+  build-mingw:
+    runs-on: ubuntu-latest
+    name: build-mingw-${{ matrix.config.arch }}
+    strategy:
+      fail-fast: false
+      matrix:
+        config:
+          - {arch: i686,   server: 2022, libgcc: dw2 }
+          - {arch: x86_64, server: 2022, libgcc: seh }
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install mingw32 environment
+        run: |
+          sudo apt update
+          sudo apt install mingw-w64 ninja-build -y
+      - name: Build
+        run: |
+          cmake -S . -B build -G Ninja -DHOST_ARCH=${{ matrix.config.arch }} -DBUILD_TESTING=ON -DCMAKE_TOOLCHAIN_FILE=cmake-toolchains/cross-mingw32.cmake
+          cmake --build build
+          cmake --install build --prefix "`pwd`/build/usr"
+          mkdir -p build/usr/test build/usr/bin
+          cp -av test/fixtures build/usr/test
+          cp -av build/uv_run_tests_a.exe build/uv_run_tests.exe \
+             `${{ matrix.config.arch }}-w64-mingw32-gcc -print-file-name=libgcc_s_${{ matrix.config.libgcc }}-1.dll` \
+             `${{ matrix.config.arch }}-w64-mingw32-gcc -print-file-name=libwinpthread-1.dll` \
+             `${{ matrix.config.arch }}-w64-mingw32-gcc -print-file-name=libatomic-1.dll` \
+             build/usr/bin
+      - name: Upload build artifacts
+        uses: actions/upload-artifact@v3
+        with:
+          name: mingw-${{ matrix.config.arch }}
+          path: build/usr/**/*
+          retention-days: 2
+
+  test-mingw:
+    runs-on: windows-${{ matrix.config.server }}
+    name: test-mingw-${{ matrix.config.arch }}
+    needs: build-mingw
+    strategy:
+      fail-fast: false
+      matrix:
+        config:
+          - {arch: i686,   server: 2022}
+          - {arch: x86_64, server: 2022}
+    steps:
+      - name: Download build artifacts
+        uses: actions/download-artifact@v2
+        with:
+          name: mingw-${{ matrix.config.arch }}
+      - name: Test
+        shell: cmd
+        run: |
+          bin\uv_run_tests_a.exe
+      - name: Test
+        shell: cmd
+        run: |
+          bin\uv_run_tests.exe

cmake-toolchains/cross-mingw32.cmake

@@ -0,0 +1,17 @@
+if(NOT HOST_ARCH)
+  message(SEND_ERROR "-DHOST_ARCH required to be specified")
+endif()
+
+list(APPEND CMAKE_TRY_COMPILE_PLATFORM_VARIABLES
+  HOST_ARCH
+  )
+
+SET(CMAKE_SYSTEM_NAME Windows)
+set(COMPILER_PREFIX "${HOST_ARCH}-w64-mingw32")
+find_program(CMAKE_RC_COMPILER NAMES ${COMPILER_PREFIX}-windres)
+find_program(CMAKE_C_COMPILER NAMES ${COMPILER_PREFIX}-gcc)
+find_program(CMAKE_CXX_COMPILER NAMES ${COMPILER_PREFIX}-g++)
+
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)