use newer compiler, g++-10 and clang

Author: andreasbuhr

.github/workflows/cmake.yml

@@ -6,6 +6,10 @@ env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
   BUILD_TYPE: Release
 
+strategy:
+  matrix:
+    compiler: [g++-10, clang]
+
 jobs:
   build:
     # The CMake configure and build commands are platform agnostic and should work equally
@@ -27,6 +31,8 @@ jobs:
       # access regardless of the host operating system
       shell: bash
       working-directory: ${{runner.workspace}}/build
+      env: 
+        CC: ${{ matrix.compiler }}
       # Note the current convention is to use the -S and -B options here to specify source 
       # and build directories, but this is only available with CMake 3.13 and higher.  
       # The CMake binaries on the Github Actions machines are (as of this writing) 3.12