Correct issues when using a cuda enabled install of vtk-m.

CMake/VTKmConfig.cmake.in

@@ -105,6 +105,12 @@ endif()
 # include the CMake modules distributed with VTKm.
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${VTKm_CMAKE_MODULE_PATH})
 
+if(VTKm_ENABLE_CUDA)
+  if (CMAKE_VERSION VERSION_LESS "3.9")
+    message(FATAL_ERROR "VTK-m with CUDA requires CMake 3.9+")
+  endif()
+endif()
+
 # This includes a host of functions used by VTK-m CMake.
 include(VTKmWrappers)
 include(VTKmRenderingContexts)

CMake/VTKmDeviceAdapters.cmake

@@ -116,7 +116,7 @@ if(VTKm_ENABLE_OPENMP AND NOT TARGET vtkm::openmp)
   endif()
 endif()
 
-if(VTKm_ENABLE_CUDA AND NOT TARGET vtkm::cuda)
+if(VTKm_ENABLE_CUDA)
   cmake_minimum_required(VERSION 3.9...3.14 FATAL_ERROR)
   enable_language(CUDA)
 
@@ -126,7 +126,7 @@ if(VTKm_ENABLE_CUDA AND NOT TARGET vtkm::cuda)
     list(APPEND CMAKE_CUDA_IMPLICIT_INCLUDE_DIRECTORIES "${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES}")
   endif()
 
-  if (NOT TARGET vtkm_cuda)
+  if (NOT TARGET vtkm_cuda OR NOT TARGET vtkm::cuda)
     add_library(vtkm_cuda INTERFACE)
     set_target_properties(vtkm_cuda PROPERTIES EXPORT_NAME vtkm::cuda)
 
@@ -261,10 +261,12 @@ if(VTKm_ENABLE_CUDA AND NOT TARGET vtkm::cuda)
     set_target_properties(vtkm_cuda PROPERTIES INTERFACE_CUDA_Architecture_Flags "${arch_flags}")
   endif()
 
-  add_library(vtkm::cuda ALIAS vtkm_cuda)
+  if (NOT TARGET vtkm::cuda)
+    add_library(vtkm::cuda ALIAS vtkm_cuda)
 
-  if(NOT VTKm_INSTALL_ONLY_LIBRARIES)
-    install(TARGETS vtkm_cuda EXPORT ${VTKm_EXPORT_NAME})
+    if(NOT VTKm_INSTALL_ONLY_LIBRARIES)
+      install(TARGETS vtkm_cuda EXPORT ${VTKm_EXPORT_NAME})
+    endif()
   endif()
 
 endif()

CMake/testing/VTKmTestInstall.cmake

@@ -18,6 +18,7 @@
 ##  this software.
 ##============================================================================
 
+# -----------------------------------------------------------------------------
 function(vtkm_test_install )
   if(NOT VTKm_INSTALL_ONLY_LIBRARIES)
     set(command_args
@@ -59,14 +60,39 @@ function(vtkm_test_install )
   endif()
 endfunction()
 
+# -----------------------------------------------------------------------------
+function(vtkm_generate_install_build_options file_loc_var)
+#This generated file ensures that the adaptor's CMakeCache ends up with
+#the same CMAKE_PREFIX_PATH that VTK-m's does, even if that has multiple
+#paths in it. It is necessary because ctest's argument parsing in the
+#custom command below destroys path separators.
+#Note: the generated file will become stale if these variables change.
+#In that case it will need manual intervention (remove it) to fix.
+file(GENERATE
+  OUTPUT "${${file_loc_var}}"
+  CONTENT
+"
+set(CMAKE_BUILD_TYPE ${CMAKE_BUILD_TYPE} CACHE STRING \"\")
+set(CMAKE_PREFIX_PATH ${install_prefix} CACHE STRING \"\")
+set(CMAKE_CXX_COMPILER ${CMAKE_CXX_COMPILER} CACHE FILEPATH \"\")
+set(CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS} CACHE STRING \"\")
+set(CMAKE_CUDA_COMPILER ${CMAKE_CUDA_COMPILER} CACHE FILEPATH \"\")
+set(CMAKE_CUDA_FLAGS ${CMAKE_CUDA_FLAGS} CACHE STRING \"\")
+set(CMAKE_CUDA_HOST_COMPILER ${CMAKE_CUDA_HOST_COMPILER} CACHE FILEPATH \"\")
+"
+)
+
+endfunction()
 
 # -----------------------------------------------------------------------------
-function(test_against_installed_vtkm dir)
+function(vtkm_test_against_install dir)
   set(name ${dir})
   set(install_prefix "${VTKm_BINARY_DIR}/CMakeFiles/_tmp_install")
   set(src_dir "${CMAKE_CURRENT_SOURCE_DIR}/${name}/")
   set(build_dir "${VTKm_BINARY_DIR}/CMakeFiles/_tmp_build/test_${name}/")
 
+  set(build_config "${build_dir}/build_options.cmake")
+  vtkm_generate_install_build_options(build_config)
 
   #determine if the test is expected to compile or fail to build. We use
   #this information to built the test name to make it clear to the user
@@ -80,11 +106,7 @@ function(test_against_installed_vtkm dir)
            --build-and-test ${src_dir} ${build_dir}
            --build-generator ${CMAKE_GENERATOR}
            --build-makeprogram ${CMAKE_MAKE_PROGRAM}
-           --build-options
-              -DCMAKE_PREFIX_PATH:STRING=${install_prefix}
-              -DCMAKE_CXX_COMPILER:FILEPATH=${CMAKE_CXX_COMPILER}
-              -DCMAKE_CUDA_COMPILER:FILEPATH=${CMAKE_CUDA_COMPILER}
-              -DCMAKE_CUDA_HOST_COMPILER:FILEPATH=${CMAKE_CUDA_HOST_COMPILER}
+           --build-options -C "${build_config}"
            )
 
   set_tests_properties(${build_name} PROPERTIES LABELS ${test_label} )

examples/CMakeLists.txt

@@ -47,6 +47,6 @@ add_subdirectory(unified_memory)
 if (VTKm_ENABLE_TESTING)
   # These need to be fast to build as they will
   # be built each time we run the test
-  test_against_installed_vtkm(rendering)
-  test_against_installed_vtkm(histogram)
+  vtkm_test_against_install(rendering)
+  vtkm_test_against_install(histogram)
 endif()

examples/demo/CMakeLists.txt

@@ -34,7 +34,6 @@ if(TARGET vtkm_rendering)
     set(srcs ${cuda_srcs})
   endif()
 
-  message(STATUS "srcs: ${srcs}")
   add_executable(Demo ${srcs})
   target_link_libraries(Demo PRIVATE vtkm_rendering)
 endif()