[clang] [CUDA] Add support for __grid_constant__ attribute (PR #114589)

[Akshay Deodhar via cfe-commits]

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@@ -12222,8 +12222,17 @@ bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
             << NewFD;
     }
 
-    if (!Redeclaration && LangOpts.CUDA)
+    if (!Redeclaration && LangOpts.CUDA) {
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akshayrdeodhar wrote:

This makes sense. Perhaps a warning? But even that might not be necessary- anyone who is using `__grid_constant__` knows what they are using it for. 

https://github.com/llvm/llvm-project/pull/114589