CUDA: Fix CUDA_STANDARD selection via cxx_std_11 with CXX_STANDARD

When C++ features require a certain C++/CUDA level, verify or update the
standard level target property for each language independently.

While at it, add missing rejection of invalid `CUDA_STANDARD` property
values.

Co-Author: Brad King <brad.king@kitware.com>
Fixes: #17519

3 files changed, 25 insertions, 0 deletions

diff --git a/Tests/Cuda/CMakeLists.txt b/Tests/Cuda/CMakeLists.txt
index de48501..8a43df5 100644
--- a/Tests/Cuda/CMakeLists.txt
+++ b/Tests/Cuda/CMakeLists.txt
@@ -2,6 +2,7 @@
 ADD_TEST_MACRO(Cuda.Complex CudaComplex)
 ADD_TEST_MACRO(Cuda.ConsumeCompileFeatures CudaConsumeCompileFeatures)
 ADD_TEST_MACRO(Cuda.ObjectLibrary CudaObjectLibrary)
+ADD_TEST_MACRO(Cuda.MixedStandardLevels MixedStandardLevels)
 ADD_TEST_MACRO(Cuda.ToolkitInclude CudaToolkitInclude)
 ADD_TEST_MACRO(Cuda.ProperLinkFlags ProperLinkFlags)
 ADD_TEST_MACRO(Cuda.WithC CudaWithC)
diff --git a/Tests/Cuda/MixedStandardLevels/CMakeLists.txt b/Tests/Cuda/MixedStandardLevels/CMakeLists.txt
new file mode 100644
index 0000000..683abe7
--- /dev/null
+++ b/Tests/Cuda/MixedStandardLevels/CMakeLists.txt
@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 3.7)
+project(CudaComplex CXX CUDA)
+
+string(APPEND CMAKE_CUDA_FLAGS " -gencode arch=compute_30,code=compute_30")
+
+set(CMAKE_CXX_STANDARD 11)
+
+add_executable(MixedStandardLevels main.cu)
+target_compile_features(MixedStandardLevels PUBLIC cxx_std_11)
+
+if(APPLE)
+  # Help the static cuda runtime find the driver (libcuda.dyllib) at runtime.
+  set_property(TARGET MixedStandardLevels PROPERTY BUILD_RPATH ${CMAKE_CUDA_IMPLICIT_LINK_DIRECTORIES})
+endif()
diff --git a/Tests/Cuda/MixedStandardLevels/main.cu b/Tests/Cuda/MixedStandardLevels/main.cu
new file mode 100644
index 0000000..d57c05a
--- /dev/null
+++ b/Tests/Cuda/MixedStandardLevels/main.cu
@@ -0,0 +1,10 @@
+
+#include <type_traits>
+
+int main(int argc, char** argv)
+{
+  // Verify that issue #17519 Setting CXX_STANDARD breaks CUDA_STANDARD
+  // selection via cxx_std_11 has been corrected
+  using returnv = std::integral_constant<int, 0>;
+  return returnv::value;
+}