configure time error reporting for STDPAR feature and CI test

Author: Puerling

.github/workflows/builds.yml

@@ -14,6 +14,8 @@ jobs:
           - os: ubuntu-22.04
           - os: ubuntu-22.04
             parallelisation: 'openmp'
+          - os: ubuntu-22.04
+            parallelisation: 'stdpar'
     env:
       BUILD_TYPE: Release
       CMAKE_FLAGS: >
@@ -33,6 +35,14 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y xorg-dev libglu1-mesa-dev libgtk-3-dev
 
+      - name: Install oneapiTBB package
+        if: matrix.os == 'ubuntu-22.04' && matrix.parallelisation == 'stdpar'
+        run: |
+          curl https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS.PUB | sudo gpg --dearmor -o /usr/share/keyrings/oneapi-archive-keyring.gpg
+          echo "deb [signed-by=/usr/share/keyrings/oneapi-archive-keyring.gpg] https://apt.repos.intel.com/oneapi all main" | sudo tee /etc/apt/sources.list.d/oneAPI.list
+          sudo apt-get update
+          sudo apt-get install -y intel-oneapi-tbb-devel
+
       - uses: actions/setup-python@v5
         with:
           python-version: '3.x'
@@ -59,6 +69,17 @@ jobs:
           -DSPIRIT_USE_OPENMP=ON
           $CMAKE_FLAGS
 
+      - name: Configure with STL parallelisation
+        if: matrix.parallelisation == 'stdpar'
+        shell: bash
+        working-directory: ${{runner.workspace}}/build
+        run: >
+          cmake $GITHUB_WORKSPACE
+          $BUILD_SYSTEM_FLAG
+          -DCMAKE_BUILD_TYPE=$BUILD_TYPE
+          $CMAKE_FLAGS
+          -DSPIRIT_USE_STDPAR=ON
+
       - name: Build
         shell: bash
         working-directory: ${{runner.workspace}}/build

core/CMake/FindTBB.cmake

@@ -232,14 +232,34 @@ endif()
 
 ######### TBB decisions ############################################
 if( SPIRIT_USE_STDPAR )
-    include( FindTBB )
+    # Try to find TBB module
+    find_package( TBB )
     if( TBB_FOUND )
-        set( SPIRIT_COMPILE_DEFINITIONS ${SPIRIT_COMPILE_DEFINITIONS} -DSPIRIT_USE_STDPAR )
+        set( TBB_LIB TBB::tbb )
         message( STATUS ">> using TBB for parallel STL" )
     else()
+        set( TBB_LIB )
         message( WARNING ">> TBB could not be found." )
-        set( SPIRIT_USE_STDPAR OFF )
     endif()
+    # All of these symbols are required to use this feature.
+    # So, if this compiles even if TBB was not found it should be fine.
+    list( APPEND CMAKE_REQUIRED_LIBRARIES ${TBB_LIB} )
+    include(CheckCXXSourceCompiles)
+    check_cxx_source_compiles("
+      #include <execution>
+      int main()
+      {
+        (void)std::execution::seq;
+        (void)std::execution::par;
+        (void)std::execution::par_unseq;
+        return 0;
+      }
+    " HAVE_CXX17_PARALLEL_ALGORITHM)
+
+    if( NOT HAVE_CXX17_PARALLEL_ALGORITHM )
+        message( FATAL_ERROR "C++17 execution policies are required for SPIRIT_USE_STDPAR=ON" )
+    endif()
+    set( SPIRIT_COMPILE_DEFINITIONS ${SPIRIT_COMPILE_DEFINITIONS} -DSPIRIT_USE_STDPAR )
 endif()
 ######### TBB decisions ############################################