diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 473c03275..a0f71a1e4 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -452,14 +452,20 @@ jobs:
       - name: Download LLVM
         run: |
           brew install llvm@${{ matrix.llvm_version }} ninja curl
-          echo "/opt/homebrew/opt/llvm@${{ matrix.llvm_version }}/bin" >> $GITHUB_PATH    
+          echo "/opt/homebrew/opt/llvm@${{ matrix.llvm_version }}/bin" >> $GITHUB_PATH  
           TMP_PATH=$(xcrun --show-sdk-path)/user/include
           echo "CPATH=$TMP_PATH" >> $GITHUB_ENV
 
       - name: CMake
+        if: matrix.llvm_version != 18
         run: |
           cmake -B build -G Ninja -DC3_LLVM_VERSION=${{matrix.llvm_version}} -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
           cmake --build build
+      - name: CMake18
+        if: matrix.llvm_version == 18
+        run: |
+          cmake -B build -G Ninja -DC3_LLVM_VERSION=${{matrix.llvm_version}}.1 -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
+          cmake --build build
 
       - name: Vendor-fetch
         run: |