analysis workflow, install expat.

.github/workflows/analysis_ports.yml

@@ -24,15 +24,19 @@ jobs:
 #            config: "CC=clang --enable-debug --disable-flto"
 #            make_test: "yes"
 #            clang_analysis: "yes"
-          - name: macos
+          - name: GCC on OS X
             os: macos-latest
-            config: "--enable-debug --disable-flto --with-ssl=/usr/local/opt/openssl"
+            install_expat: "yes"
+            config: "--enable-debug --disable-flto --with-ssl=/usr/local/opt/openssl --with-libexpat=/usr/local/opt/expat"
             make_test: "yes"
  
     steps:
       - uses: actions/checkout@v2
         with:
           submodules: false
+      - name: install expat
+        if: ${{ matrix.install_expat == 'yes' }}
+        run: brew install expat
       - name: configure
         run: ./configure ${{ matrix.config }}
       - name: make