From a4b60d948dabf91764deeab14b786858d978913d Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Mon, 7 Oct 2024 11:58:57 -0400
Subject: [PATCH] FindOpenMP: Add support for CUDA when compiling with Clang

---
 .gitlab/ci/configure_cuda12.2_clang.cmake | 2 ++
 Help/release/dev/FindOpenMP-CUDA.rst      | 3 +--
 Modules/FindOpenMP.cmake                  | 8 +++-----
 Tests/FindOpenMP/Test/main.c              | 2 +-
 4 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/.gitlab/ci/configure_cuda12.2_clang.cmake b/.gitlab/ci/configure_cuda12.2_clang.cmake
index 8f10f862d1..ce4afaa33d 100644
--- a/.gitlab/ci/configure_cuda12.2_clang.cmake
+++ b/.gitlab/ci/configure_cuda12.2_clang.cmake
@@ -1,4 +1,6 @@
 set(CMake_TEST_CUDA "Clang" CACHE STRING "")
 set(CMake_TEST_CUDA_STANDARDS "03;11;14;17;20;23" CACHE STRING "")
+set(CMake_TEST_FindOpenMP "ON" CACHE BOOL "")
+set(CMake_TEST_FindOpenMP_CUDA "ON" CACHE BOOL "")
 
 include("${CMAKE_CURRENT_LIST_DIR}/configure_external_test.cmake")
diff --git a/Help/release/dev/FindOpenMP-CUDA.rst b/Help/release/dev/FindOpenMP-CUDA.rst
index 388085515c..9c21d5318f 100644
--- a/Help/release/dev/FindOpenMP-CUDA.rst
+++ b/Help/release/dev/FindOpenMP-CUDA.rst
@@ -1,5 +1,4 @@
 FindOpenMP-CUDA
 ---------------
 
-* The :module:`FindOpenMP` module gained support for ``CUDA`` when using
-  a CUDA compiler that supports OpenMP on the host.
+* The :module:`FindOpenMP` module gained support for the ``CUDA`` language.
diff --git a/Modules/FindOpenMP.cmake b/Modules/FindOpenMP.cmake
index 32e4cf238f..07eaf66188 100644
--- a/Modules/FindOpenMP.cmake
+++ b/Modules/FindOpenMP.cmake
@@ -183,12 +183,10 @@ set(OpenMP_C_CXX_TEST_SOURCE
 int main(void) {
 #ifdef _OPENMP
   omp_get_max_threads();
-  return 0;
-#elif defined(__HIP_DEVICE_COMPILE__)
-  return 0;
-#else
-  breaks_on_purpose
+#elif !defined(__CUDA_ARCH__) && !defined(__HIP_DEVICE_COMPILE__)
+#  error \"_OPENMP not defined!\"
 #endif
+  return 0;
 }
 ")
 
diff --git a/Tests/FindOpenMP/Test/main.c b/Tests/FindOpenMP/Test/main.c
index f7abef85bb..f60fce8b3c 100644
--- a/Tests/FindOpenMP/Test/main.c
+++ b/Tests/FindOpenMP/Test/main.c
@@ -3,7 +3,7 @@ int main(void)
 {
 #ifdef _OPENMP
   omp_get_num_threads();
-#else
+#elif !defined(__CUDA_ARCH__) && !defined(__HIP_DEVICE_COMPILE__)
 #  error "_OPENMP not defined!"
 #endif
   return 0;