Downgrade clang

Signed-off-by: rahul shrivastava <[email protected]>

Author: rahuls-cerebras

.github/workflows/ci.yml

@@ -27,6 +27,17 @@ jobs:
     env:
       CACHE_DIR: ${{ github.workspace }}/.container-cache
     steps:
+      - name: Install Clang 17.0.6
+        run: |
+          yum update -y
+          yum install -y wget
+          wget https://apt.llvm.org/llvm.sh
+          chmod +x llvm.sh
+          ./llvm.sh 17
+          yum install -y clang-17 lldb-17 lld-17 clang-tools-extra-17
+          echo "Clang version installed:"
+      - name: Verify Clang installation
+        run: clang --version
       - name: Configure local git mirrors
         run: |
           # Our stock runners have access to certain local git caches. If these

build_tools/ci/build_posix.sh

@@ -50,7 +50,7 @@ cmake -S "$repo_root/externals/llvm-project/llvm" -B "$build_dir" \
   -DLLVM_EXTERNAL_TORCH_MLIR_SOURCE_DIR="$repo_root" \
   -DLLVM_TARGETS_TO_BUILD=host \
   -DMLIR_ENABLE_BINDINGS_PYTHON=ON \
-  -DTORCH_MLIR_ENABLE_LTC=OFF \
+  -DTORCH_MLIR_ENABLE_LTC=ON \
   -DTORCH_MLIR_ENABLE_PYTORCH_EXTENSIONS=ON
 echo "::endgroup::"