Reduce scope of Thrust linkage in cudax. (#2496)

It's only used for tests, it doesn't need to be linked to all cudax targets.

Author: alliepiper

cudax/cmake/cudaxBuildTargetList.cmake

@@ -107,21 +107,13 @@ function(_cn_init_target_list)
   set(cudax_TARGETS "" CACHE INTERNAL "" FORCE)
 endfunction()
 
-# Bring in thrust as a dev dependency, only used in tests:
-find_package(Thrust ${cudax_VERSION} EXACT CONFIG
-  NO_DEFAULT_PATH # Only check the explicit path in HINTS:
-  HINTS "${CCCL_SOURCE_DIR}/lib/cmake/thrust/"
-)
-thrust_create_target(cudax::Thrust)
-
 function(_cn_add_target_to_target_list target_name dialect prefix)
   add_library(${target_name} INTERFACE)
 
   cudax_set_target_properties(${target_name} ${dialect} ${prefix})
 
   target_link_libraries(${target_name} INTERFACE
     cudax::cudax
-    cudax::Thrust
     cudax.compiler_interface_cpp${dialect}
   )
 

cudax/test/CMakeLists.txt

@@ -1,6 +1,12 @@
 include("${cudax_SOURCE_DIR}/cmake/CPM.cmake")
 CPMAddPackage("gh:catchorg/[email protected]")
 
+find_package(Thrust ${cudax_VERSION} EXACT CONFIG
+  NO_DEFAULT_PATH # Only check the explicit path in HINTS:
+  HINTS "${CCCL_SOURCE_DIR}/lib/cmake/thrust/"
+)
+thrust_create_target(cudax.test.thrust)
+
 add_library(catch2_main STATIC catch2_helpers/catch2_main.cpp)
 target_link_libraries(catch2_main PUBLIC Catch2::Catch2)
 
@@ -24,9 +30,16 @@ function(cudax_add_catch2_test target_name_var test_name cn_target) # ARGN=test
 
   add_executable(${test_target} ${test_sources})
   target_include_directories(${test_target} PRIVATE "common")
-  target_link_libraries(${test_target} PRIVATE ${cn_target} Catch2::Catch2 catch2_main)
-  target_compile_options(${test_target} PRIVATE "-DLIBCUDACXX_ENABLE_EXPERIMENTAL_MEMORY_RESOURCE")
-  target_compile_options(${test_target} PRIVATE $<$<COMPILE_LANG_AND_ID:CUDA,NVIDIA>:--extended-lambda>)
+  target_link_libraries(${test_target} PRIVATE
+    ${cn_target}
+    cudax.test.thrust
+    Catch2::Catch2
+    catch2_main
+  )
+  target_compile_options(${test_target} PRIVATE
+    "-DLIBCUDACXX_ENABLE_EXPERIMENTAL_MEMORY_RESOURCE"
+    $<$<COMPILE_LANG_AND_ID:CUDA,NVIDIA>:--extended-lambda>
+  )
   cudax_clone_target_properties(${test_target} ${cn_target})
   set_target_properties(${test_target} PROPERTIES
     CUDA_ARCHITECTURES "${CMAKE_CUDA_ARCHITECTURES}"

lib/cmake/cudax/cudax-config.cmake

@@ -48,7 +48,7 @@ if (cudax_NO_IMPORTED_TARGETS)
   add_library(_cudax_cudax INTERFACE)
   add_library(cudax::cudax ALIAS _cudax_cudax)
   set(cn_target_name _cudax_cudax)
-  else()
+else()
   add_library(cudax::cudax INTERFACE IMPORTED GLOBAL)
   set(cn_target_name cudax::cudax)
 endif()