VS: Don't compute CUDA options unless necessary

In the following scenario (with 3.18 policies):
1. A CXX target is created.
2. CUDA language is enabled.

CMake 3.18 introduced CMP0104, which requires CUDA_ARCHITECTURES to be
set.  Because the CXX target was created before CUDA was enabled it
wouldn't have it set.  The Visual Studio generator would however end up
computing CUDA compile options for the CXX target, which would result in
a fatal error due to the policy violation.

There doesn't seem to be a reason to do this for targets that don't
actually use the CUDA language, so we can skip and generate the CXX
target just fine.

Fixes: #21341

1 files changed, 4 insertions, 2 deletions

diff --git a/Source/cmVisualStudio10TargetGenerator.cxx b/Source/cmVisualStudio10TargetGenerator.cxx
index f58c6fd..2ea2839 100644
--- a/Source/cmVisualStudio10TargetGenerator.cxx
+++ b/Source/cmVisualStudio10TargetGenerator.cxx
@@ -3018,7 +3018,8 @@ bool cmVisualStudio10TargetGenerator::ComputeCudaOptions()
     return true;
   }
   for (std::string const& c : this->Configurations) {
-    if (!this->ComputeCudaOptions(c)) {
+    if (this->GeneratorTarget->IsLanguageUsed("CUDA", c) &&
+        !this->ComputeCudaOptions(c)) {
       return false;
     }
   }
@@ -3158,7 +3159,8 @@ bool cmVisualStudio10TargetGenerator::ComputeCudaOptions(
 void cmVisualStudio10TargetGenerator::WriteCudaOptions(
   Elem& e1, std::string const& configName)
 {
-  if (!this->MSTools || !this->GlobalGenerator->IsCudaEnabled()) {
+  if (!this->MSTools || !this->GlobalGenerator->IsCudaEnabled() ||
+      !this->GeneratorTarget->IsLanguageUsed("CUDA", configName)) {
     return;
   }
   Elem e2(e1, "CudaCompile");