Older ubuntu versions (#16)

.github/workflows/test.yml

@@ -1,30 +1,13 @@
 name: Test
-on: [push]
+on: [ push ]
 jobs:
 
-#  lint:
-#    runs-on: ubuntu-20.04
-#    steps:
-#      - uses: actions/checkout@v2
-#      - uses: actions/setup-go@v2
-#        with:
-#          go-version: 1.14.x
-#
-#      - name: Install dependencies
-#        run: sudo apt update && sudo apt install make libc-dev gcc g++
-#
-#      - name: lint
-#        uses: golangci/golangci-lint-action@v1
-#        with:
-#          version: v1.29
-#          only-new-issues: true
-
   test:
     strategy:
       matrix:
-        os: [ubuntu-20.04, macos-10.15] # list of os: https://github.com/actions/virtual-environments
-#        os: [ubuntu-20.04, macos-10.15, windows-latest] # list of os: https://github.com/actions/virtual-environments
-        go: [ '1.15', '1.13' ]
+        os: [ ubuntu-16.04, ubuntu-18.04, ubuntu-20.04, macos-10.15 ] # list of os: https://github.com/actions/virtual-environments
+        #        os: [ubuntu-20.04, macos-10.15, windows-latest] # list of os: https://github.com/actions/virtual-environments
+        go: [ '1.16', '1.13' ]
     runs-on: ${{ matrix.os }}
 
     steps:
@@ -45,7 +28,7 @@ jobs:
           key: go-${{ matrix.os }}-${{ matrix.go }}-${{ hashFiles('**/go.sum') }}
 
       - name: Test
-        run: make test
+        run: cc --version && make test
 
       - name: Race
         run: make race