Add clang to compilers on GitHub.

diff --git a/.github/workflows/buildtest.yml b/.github/workflows/buildtest.yml
index 2c0d83ab8af9280b1c8f7bd71dbfbd096dfc10ee..a321898b60aeaaaeeb6ee4ce9df4b6026633ceae 100644 (file)
--- a/.github/workflows/buildtest.yml
+++ b/.github/workflows/buildtest.yml
@@ -6,6 +6,12 @@ env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
   BUILD_TYPE: Release
 
+strategy:
+  matrix:
+    compiler:
+      - { CC: gcc, CXX: g++ }
+      - { CC: clang, CXX: clang++ }
+
 jobs:
   build:
     # The CMake configure and build commands are platform agnostic and should work equally
@@ -30,6 +36,9 @@ jobs:
       # access regardless of the host operating system
       shell: bash
       working-directory: ${{runner.workspace}}/build
+      env:
+        CC: ${{ matrix.compiler.CC }}
+        CXX: ${{ matrix.compiler.CXX }}
       # 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