Remove outdated brew clang in MacOS 14

Author: simonlegrand

.github/workflows/full-mpich.yml

@@ -82,19 +82,24 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - name: Set environment
+        run: |
+          if [ "${{ matrix.version }}" -lt "15" ]; then
+            echo "CXX=g++ -Wl,-ld_classic -Wl,-commons,use_dylibs -Wno-unused-command-line-argument" >> $GITHUB_ENV
+            echo "LLVM_VERSION=15" >> $GITHUB_ENV
+          elif [ "${{ matrix.version }}" -eq "15" ]; then
+            echo "LLVM_VERSION=18" >> $GITHUB_ENV
+          fi
+
       - name: Install
         run: |
           brew install gcc m4 git bison hdf5 cmake wget autoconf automake
+          brew remove llvm@$LLVM_VERSION
 
       - name: Symlink GCC & Fortran
         run: ./etc/actions/macos/link_fortran.sh "$(uname -p)"
 
-      - name: Set ld_classic based on macOS version
-        run: |
-          if [ "${{ matrix.version }}" -ne "15" ]; then
-            echo "CXX=g++ -Wl,-ld_classic -Wl,-commons,use_dylibs -Wno-unused-command-line-argument" >> $GITHUB_ENV
-          fi
-          
+                
       - name: Configure
         run: |
           autoreconf -i