compile_features: Ignore features that map to languages that aren't enabled

Remove the Cuda/ConsumeCompileFeatures test as it only existed to
validate that using `cxx_std_XY` would cause the paired language (CUDA) to also build in mode XY.

Help/release/dev/target_compile_features-ignore-disabled-langs.rst

@@ -0,0 +1,5 @@
+target_compile_features-ignore-disabled-langs
+---------------------------------------------
+
+* :command:`target_compile_features` learned to ignored features for languages that
+  aren't enabled.

Source/cmStandardLevelResolver.cxx

@@ -387,6 +387,10 @@ bool cmStandardLevelResolver::CheckCompileFeaturesAvailable(
     return false;
   }
 
+  if (!this->Makefile->GetGlobalGenerator()->GetLanguageEnabled(lang)) {
+    return true;
+  }
+
   const char* features = this->CompileFeaturesAvailable(lang, error);
   if (!features) {
     return false;

Tests/Cuda/CMakeLists.txt

@@ -4,7 +4,6 @@ macro (add_cuda_test_macro name)
     PROPERTY LABELS "CUDA")
 endmacro ()
 
-add_cuda_test_macro(Cuda.ConsumeCompileFeatures CudaConsumeCompileFeatures)
 add_cuda_test_macro(Cuda.CXXStandardSetTwice CXXStandardSetTwice)
 add_cuda_test_macro(Cuda.ObjectLibrary CudaObjectLibrary)
 add_cuda_test_macro(Cuda.MixedStandardLevels1 MixedStandardLevels1)

Tests/Cuda/ConsumeCompileFeatures/CMakeLists.txt

@@ -1,16 +0,0 @@
-cmake_minimum_required(VERSION 3.18)
-project(ConsumeCompileFeatures CXX CUDA)
-#Goal for this example:
-
-#build a c++11 library that express a c++11 public compile feature
-#link a cuda library and verify it builds with c++11 enabled
-
-#build a standalone c++/cuda mixed executable where we express a c++11
-#compile feature.
-
-
-add_library(CudaConsumeLib STATIC static.cpp static.cu)
-target_compile_features(CudaConsumeLib PUBLIC cxx_nullptr)
-
-add_executable(CudaConsumeCompileFeatures main.cu)
-target_link_libraries(CudaConsumeCompileFeatures PRIVATE CudaConsumeLib)

Tests/Cuda/ConsumeCompileFeatures/main.cu

@@ -1,20 +0,0 @@
-
-#include <iostream>
-
-int static_cxx11_func(int);
-
-void test_functions()
-{
-  auto x = static_cxx11_func(int(42));
-  std::cout << x << std::endl;
-}
-
-int main(int argc, char** argv)
-{
-  test_functions();
-  std::cout
-    << "this executable doesn't use cuda code, just call methods defined"
-    << std::endl;
-  std::cout << "in libraries that have cuda code" << std::endl;
-  return 0;
-}

Tests/Cuda/ConsumeCompileFeatures/static.cpp

@@ -1,10 +0,0 @@
-
-
-#include <type_traits>
-
-int static_cuda11_func(int);
-
-int static_cxx11_func(int x)
-{
-  return static_cuda11_func(x) + std::integral_constant<int, 32>::value;
-}

Tests/Cuda/ConsumeCompileFeatures/static.cu

@@ -1,9 +0,0 @@
-
-#include <type_traits>
-
-using tt = std::true_type;
-using ft = std::false_type;
-int __host__ static_cuda11_func(int x)
-{
-  return x * x + std::integral_constant<int, 17>::value;
-}

Tests/RunCMake/target_compile_features/cxx_not_enabled-stderr.txt

@@ -1,4 +1,2 @@
-^CMake Error at cxx_not_enabled.cmake:[0-9]+ \(target_compile_features\):
-  target_compile_features cannot use features from non-enabled language CXX
-Call Stack \(most recent call first\):
-  CMakeLists\.txt:[0-9]+ \(include\)$
+^CMake Error:.*CMake can not determine linker language for target: main.*
+CMake Generate step failed.  Build files cannot be regenerated correctly.$