diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 0fa1f426..191d83bb 100755
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -16,15 +16,15 @@ jobs:
     steps:
       - name: Clone project
         uses: actions/checkout@v2
-      #- name: Install LLVM 12
-      #  if: ${{ job.name == macos-latest-llvm@12 }}
-      #  shell: bash
-      #  run: |
-      #    set -ex
-      #    brew install llvm@12
-      #    echo "/opt/homebrew/opt/llvm@12/bin" >> "${GITHUB_PATH}"
-      #    echo LDFLAGS="-L/opt/homebrew/opt/llvm@12/lib" >> "${GITHUB_ENV}"
-      #    echo CPPFLAGS="-I/opt/homebrew/opt/llvm@12/include" >> "${GITHUB_ENV}"
+      - name: Install LLVM 12
+        if: ${{ job.name == macos-latest-llvm@12 }}
+        shell: bash
+        run: |
+          set -ex
+          brew install llvm@12
+          echo "/opt/homebrew/opt/llvm@12/bin" >> "${GITHUB_PATH}"
+          echo LDFLAGS="-L/opt/homebrew/opt/llvm@12/lib" >> "${GITHUB_ENV}"
+          echo CPPFLAGS="-I/opt/homebrew/opt/llvm@12/include" >> "${GITHUB_ENV}"
       #- name: Setup Haskell
       #  uses: haskell-actions/setup@v2.7.5
       #  with: