[clang] [lldb] [HLSL] Implement intangible AST type (PR #97362)

[Chris B via cfe-commits]

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@@ -8001,6 +8001,12 @@ NamedDecl *Sema::ActOnVariableDeclarator(
     }
   }
 
+  if (getLangOpts().HLSL) {
+    if (R->isHLSLSpecificType() && !NewVD->isImplicit()) {
+      Diag(D.getBeginLoc(), diag::err_hlsl_intangible_type_cannot_be_declared);
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llvm-beanz wrote:

`NewVD->isImplicit()` means the declaration is implicit and doesn't have any source, that prevents us from being able to use these in `hlsl.h` or directly in tests. I think that restriction may be more than we need.

https://github.com/llvm/llvm-project/pull/97362