[clang] [clang]: reflection operator parsing for global namespace and primitive types (PR #164692)

[via cfe-commits]

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@@ -1848,6 +1848,11 @@ def err_placeholder_expected_auto_or_decltype_auto : Error<
   "expected 'auto' or 'decltype(auto)' after concept name">;
 }
 
+let CategoryName = "Reflection Issue" in {
+def err_cannot_reflect_operand : Error<
+  "cannot reflect the provided operand">;
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Sirraide wrote:

So this diagnostic should probably be more specific in what the operand is; I don’t think it makes sense to print the operand for this diagnostic specifically, but printing reflexions elsewhere sounds like a good idea; that might require adding support for printing reflexions to `clang::FormatASTNodeDiagnosticArgument` and/or a new diagnostic argument kind depending on how they end up being represented in the AST.

https://github.com/llvm/llvm-project/pull/164692