Fixed CMakeLists.txt for mesh tests

src/UnitTests/Meshes/CMakeLists.txt

 ADD_EXECUTABLE( BoundaryTagsTest${mpiExt}${debugExt} ${headers} BoundaryTagsTest.cpp )
-SET_TARGET_PROPERTIES( BoundaryTagsTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+TARGET_COMPILE_OPTIONS( BoundaryTagsTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
 TARGET_LINK_LIBRARIES( BoundaryTagsTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                            tnl${mpiExt}${debugExt}-${tnlVersion} )
 
 if( BUILD_CUDA AND ${CMAKE_CXX_COMPILER} MATCHES ".*clang\\+\\+" )
    # FIXME: nvcc fails with "Invalid memory reference" error, so we assume that ${CXX} is clang++
-   #CUDA_ADD_EXECUTABLE( MeshTest${mpiExt}${debugExt} ${headers} MeshTest.cu OPTIONS "${CXX_TESTS_FLAGS}" )
+   #CUDA_ADD_EXECUTABLE( MeshTest${mpiExt}${debugExt} ${headers} MeshTest.cu OPTIONS ${CXX_TESTS_FLAGS} )
    #TARGET_LINK_LIBRARIES( MeshTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
    #                                                        tnl${mpiExt}${debugExt}-${tnlVersion} )
    ADD_EXECUTABLE( MeshTest${mpiExt}${debugExt} ${headers} MeshTest.cpp )
-   SET_TARGET_PROPERTIES( MeshTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS
-                          "${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21" )
+   TARGET_COMPILE_OPTIONS( MeshTest${mpiExt}${debugExt} PRIVATE
+                          ${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21 )
    TARGET_LINK_LIBRARIES( MeshTest${mpiExt}${debugExt}
                           ${GTEST_BOTH_LIBRARIES}
                           tnl${mpiExt}${debugExt}-${tnlVersion}
                           cudart dl rt "-L ${CUDA_TOOLKIT_ROOT_DIR}/lib64/" )
 
    ADD_EXECUTABLE( MeshOrderingTest${mpiExt}${debugExt} ${headers} MeshOrderingTest.cpp )
-   SET_TARGET_PROPERTIES( MeshOrderingTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS
-                          "${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21" )
+   TARGET_COMPILE_OPTIONS( MeshOrderingTest${mpiExt}${debugExt} PRIVATE
+                          ${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21 )
    TARGET_LINK_LIBRARIES( MeshOrderingTest${mpiExt}${debugExt}
                           ${GTEST_BOTH_LIBRARIES}
                           tnl${mpiExt}${debugExt}-${tnlVersion}
                           cudart dl rt "-L ${CUDA_TOOLKIT_ROOT_DIR}/lib64/" )
 else()
    ADD_EXECUTABLE( MeshTest${mpiExt}${debugExt} ${headers} MeshTest.cpp )
-   SET_TARGET_PROPERTIES( MeshTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+   TARGET_COMPILE_OPTIONS( MeshTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
    TARGET_LINK_LIBRARIES( MeshTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                               tnl${mpiExt}${debugExt}-${tnlVersion} )
 
    ADD_EXECUTABLE( MeshOrderingTest${mpiExt}${debugExt} ${headers} MeshOrderingTest.cpp )
-   SET_TARGET_PROPERTIES( MeshOrderingTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+   TARGET_COMPILE_OPTIONS( MeshOrderingTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
    TARGET_LINK_LIBRARIES( MeshOrderingTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                               tnl${mpiExt}${debugExt}-${tnlVersion} )
 endif()
 
 ADD_EXECUTABLE( MeshEntityTest${mpiExt}${debugExt} ${headers} MeshEntityTest.cpp )
-SET_TARGET_PROPERTIES( MeshEntityTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+TARGET_COMPILE_OPTIONS( MeshEntityTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
 TARGET_LINK_LIBRARIES( MeshEntityTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                            tnl${mpiExt}${debugExt}-${tnlVersion} )
 
 ADD_EXECUTABLE( MultimapTest${mpiExt}${debugExt} ${headers} MultimapTest.cpp )
-SET_TARGET_PROPERTIES( MultimapTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+TARGET_COMPILE_OPTIONS( MultimapTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
 TARGET_LINK_LIBRARIES( MultimapTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                            tnl${mpiExt}${debugExt}-${tnlVersion} )
 
 ADD_EXECUTABLE( StaticMultimapTest${mpiExt}${debugExt} ${headers} StaticMultimapTest.cpp )
-SET_TARGET_PROPERTIES( StaticMultimapTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+TARGET_COMPILE_OPTIONS( StaticMultimapTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
 TARGET_LINK_LIBRARIES( StaticMultimapTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
                                                            tnl${mpiExt}${debugExt}-${tnlVersion} )
 
@@ -74,14 +74,14 @@ endif( VTK_FOUND )
 
 if( BUILD_CUDA AND ${CMAKE_CXX_COMPILER} MATCHES ".*clang\\+\\+" )
    # FIXME: nvcc fails with "Invalid memory reference" error, so we assume that ${CXX} is clang++
-   #CUDA_ADD_EXECUTABLE( MeshReaderTest${mpiExt}${debugExt} ${headers} MeshTest.cu OPTIONS "${CXX_TESTS_FLAGS}" )
+   #CUDA_ADD_EXECUTABLE( MeshReaderTest${mpiExt}${debugExt} ${headers} MeshTest.cu OPTIONS ${CXX_TESTS_FLAGS} )
    #TARGET_LINK_LIBRARIES( MeshReaderTest${mpiExt}${debugExt} ${GTEST_BOTH_LIBRARIES}
    #                                                        vtkCommonCore
    #                                                        vtkIOLegacy
    #                                                        tnl${mpiExt}${debugExt}-${tnlVersion} )
    ADD_EXECUTABLE( MeshReaderTest${mpiExt}${debugExt} ${headers} MeshReaderTest.cpp )
-   SET_TARGET_PROPERTIES( MeshReaderTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS
-                          "${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21" )
+   TARGET_COMPILE_OPTIONS( MeshReaderTest${mpiExt}${debugExt} PRIVATE
+                          ${CXX_TESTS_FLAGS} -DHAVE_CUDA -x cuda --cuda-path=${CUDA_TOOLKIT_ROOT_DIR} --cuda-gpu-arch=sm_21 )
    TARGET_LINK_LIBRARIES( MeshReaderTest${mpiExt}${debugExt}
                           ${GTEST_BOTH_LIBRARIES}
                           ${VTK_COMMON_LIBRARIES}
@@ -89,7 +89,7 @@ if( BUILD_CUDA AND ${CMAKE_CXX_COMPILER} MATCHES ".*clang\\+\\+" )
                           cudart dl rt "-L ${CUDA_TOOLKIT_ROOT_DIR}/lib64/" )
 else()
    add_executable( MeshReaderTest${mpiExt}${debugExt} MeshReaderTest.cpp )
-   set_target_properties( MeshReaderTest${mpiExt}${debugExt} PROPERTIES COMPILE_FLAGS "${CXX_TESTS_FLAGS}" )
+   target_compile_options( MeshReaderTest${mpiExt}${debugExt} PRIVATE ${CXX_TESTS_FLAGS} )
 
    #target_link_libraries( MeshReaderTest${mpiExt}${debugExt}
    #                       ${VTK_LIBRARIES}