Actions: Refactor for mac.

Author: tadd

.github/workflows/c-test.yml

@@ -28,13 +28,12 @@ jobs:
     steps:
     - uses: actions/checkout@v5
     - run: |
-        brew update
         brew install criterion coreutils
         echo CPATH="/opt/homebrew/include:$CPATH" >> "$GITHUB_ENV"
         echo LIBRARY_PATH="/opt/homebrew/lib:$LIBRARY_PATH" >> "$GITHUB_ENV"
         echo DYLD_LIBRARY_PATH=. >> "$GITHUB_ENV"
         echo MAKEFLAGS=-j3 >> "$GITHUB_ENV"
     - name: Test
-      run: make test CC=clang
+      run: make test
     - name: Test -O3
-      run: make clean && make test CC=clang XCFLAGS='-O3 -g0'
+      run: make clean && make test XCFLAGS='-O3 -g0'