Add Windows to the CI matrix.

.github/workflows/ccpp.yml

@@ -6,7 +6,7 @@ jobs:
   build-linux:
     runs-on: ubuntu-20.04
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: apt
       run: sudo apt update && sudo apt install bison flex ninja-build
     - name: make
@@ -15,9 +15,32 @@ jobs:
   build-macos:
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: brew
       run: brew install ninja
     - name: make
       run: make
 
+  build-windows:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: msys2 {0}
+    steps:
+    - uses: msys2/setup-msys2@v2
+      with:
+        update: true
+        msystem: MINGW32
+        install: >-
+          make
+          mingw-w64-i686-gcc
+          mingw-w64-i686-lua
+          ninja
+          bison
+          flex
+          zip
+    - uses: actions/checkout@v3
+    - name: build
+      run: |
+        make
+