add GitHub CI job

.github/workflows/build.yml

@@ -0,0 +1,37 @@
+name: build
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+            cc: clang
+          - os: ubuntu-latest
+            cc: gcc
+    runs-on: ${{ matrix.os }}
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Install Linux dependencies
+      if: runner.os == 'Linux'
+      run: |
+        sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu `lsb_release -sc` main universe"
+        sudo apt-get update -y -qq
+        sudo apt-get install meson ninja-build
+
+    - name: Execute build
+      env:
+        CC: ${{ matrix.cc }}
+      run: |
+        meson setup build
+        cd build && ninja