Updated Ubuntu GitHub action to LLVM 18 (#296)

Author: bkryza

.github/workflows/build.yml

@@ -26,7 +26,7 @@ on:
 
 jobs:
   build-ubuntu:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
     - name: Checkout repository
       uses: actions/checkout@v4
@@ -37,17 +37,13 @@ jobs:
       with:
         max-size: "2000M"
     - name: Install deps
-      run: sudo apt -y install git make pkg-config gcc-11 g++-11 ccache cmake libyaml-cpp-dev llvm-15 clang-15 libclang-15-dev libclang-cpp15-dev clang-format-15 lcov zlib1g-dev libunwind-dev libdw-dev gnustep-back-common libgnustep-base-dev gnustep-make
-    - name: Select g++ version
-      run: |
-        sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 11
-        sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-11 11
+      run: sudo apt -y install git make ninja-build pkg-config gcc g++ ccache cmake libyaml-cpp-dev llvm-18 clang-18 libclang-18-dev libclang-cpp18-dev clang-format-18 lcov zlib1g-dev libunwind-dev libdw-dev gnustep-back-common libgnustep-base-dev gnustep-make
     - name: Check code formatting
       run: |
         make check-formatting
     - name: Build and unit test
       run: |
-        NUMPROC=2 CODE_COVERAGE=ON LLVM_VERSION=15 ENABLE_OBJECTIVE_C_TEST_CASES=ON FETCH_LIBOBJC2=ON make test
+        CC=/usr/bin/clang-18 CXX=/usr/bin/clang++-18 LLVM_VERSION=18 NUMPROC=2 CMAKE_GENERATOR=Ninja CODE_COVERAGE=ON LLVM_VERSION=18 ENABLE_CXX_MODULES_TEST_CASES=ON ENABLE_CUDA_TEST_CASES=OFF ENABLE_OBJECTIVE_C_TEST_CASES=ON FETCH_LIBOBJC2=ON CLANG_UML_ENABLE_BACKTRACE=ON make test
     - name: Run coverage
       run: |
         lcov -c -d debug -o coverage.info