Test for ccache

.github/workflows/ccache-test.yml

@@ -0,0 +1,32 @@
+name: CCache test
+
+permissions:
+  contents: read
+
+on:
+  push:
+
+jobs:
+  ccache-test:
+    runs-on: macos-13
+    steps:
+      - name: Setup ccache
+        uses: hendrikmuhs/ccache-action@v1
+        with:
+          # A full build of llvm, clang, lld, and lldb takes about 250MB
+          # of ccache space. There's not much reason to have more than this,
+          # because we usually won't need to save cache entries from older
+          # builds.  Also, there is an overall 10GB cache limit, and each
+          # run creates a new cache entry so we want to ensure that we have
+          # enough cache space for all the tests to run at once and still
+          # fit under the 10 GB limit.
+          max-size: 500M
+          key: ${{ matrix.os }}-ccache-test
+          variant: sccache
+
+     - name: Test ccache
+       run: |
+         echo "int main(){}" > test.c
+         SCCACHE_DEBUG=verbose sccache clang test.c
+         sccache -s
+