Create libcxx_msan.yml

.github/workflows/libcxx_msan.yml

@@ -0,0 +1,36 @@
+name: Build libc++ for MemorySanitizer
+
+on: [workflow_dispatch]
+
+jobs:
+  build-libcxx_msan:
+
+    runs-on: ubuntu-22.04
+
+    steps:
+    - name: Install dependencies
+      run: |
+        sudo apt update
+        sudo apt install -y git cmake ninja-build
+
+    - name: Install clang
+      run: |
+        wget https://apt.llvm.org/llvm.sh
+        chmod +x llvm.sh
+        sudo ./llvm.sh 16
+
+    - name: Build libcxx_msan
+      run: |
+        git clone --depth=1 https://github.com/llvm/llvm-project -b release/16.x
+        cd llvm-project
+        mkdir build
+        cmake -G Ninja -S runtimes -B build -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi" -DCMAKE_C_COMPILER=clang-16 -DCMAKE_CXX_COMPILER=clang++-16 -DLLVM_USE_SANITIZER=MemoryWithOrigins
+        ninja -C build cxx cxxabi
+        cd build
+        XZ_OPT=-e9 tar cfJ libcxx_msan.tar.xz include lib
+
+    - name: Archive libcxx_msan.tar.xz
+      uses: actions/upload-artifact@v3
+      with:
+        name: libcxx_msan
+        path: llvm-project/build/libcxx_msan.tar.xz