Only test libc++ on latest clang since its a fairly unusual config an…

…d unlikely to matter since qthreads is mostly C.

.github/workflows/CI.yml

@@ -45,7 +45,6 @@ jobs:
  clang_version: [11, 12, 13, 14, 15, 16, 17]
  scheduler: [nemesis, sherwood]
  topology: [hwloc, binders, no]
- use_libcxx: [true, false] # check with libc++ too since there are plans to expand the use of C++ in qthreads
  include:
  - clang_version: 11
  gcc_version: 10
@@ -64,7 +63,6 @@ jobs:
  env:
  CC: clang-${{ matrix.clang_version }}
  CXX: clang++${{ matrix.clang_version }}
- CXXFLAGS: ${{ matrix.use_libcxx && '-stdlib=libc++' || '' }}
  steps:
  - uses: actions/checkout@v3
  - if: ${{ matrix.clang_version == '16' || matrix.clang_version == 17 }}
@@ -73,12 +71,10 @@ jobs:
  sudo apt-add-repository 'deb https://apt.llvm.org/jammy/ llvm-toolchain-jammy-${{ matrix.clang_version }} main' && break || sleep 1
  - if: ${{ matrix.gcc_version == '13' && ! matrix.use_libcxx }}
  run: sudo apt-add-repository 'ppa:ubuntu-toolchain-r/test' && break || sleep 1
- - if: ${{ ! matrix.use_libcxx }}
+ - name: install gcc
  run: sudo apt-get install gcc-${{ matrix.gcc_version }} g++-${{ matrix.gcc_version }}
  - name: install clang
  run: sudo apt-get install clang-${{ matrix.clang_version }}
- - if: ${{ matrix.use_libcxx }}
- run: sudo apt-get install libc++-${{ matrix.clang_version }}-dev libc++abi-${{ matrix.clang_version }}-dev
  - if: ${{ matrix.topology != 'no' }}
  run: |
  sudo apt-get install hwloc libhwloc-dev