[clang] [clang]: support std::meta::info for primitive types (PR #190356)

[Timm Baeder via cfe-commits]

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@@ -314,13 +316,16 @@ class APValue {
     const AddrLabelExpr* LHSExpr;
     const AddrLabelExpr* RHSExpr;
   };
+  struct ReflectionData {
+    const ReflectionKind OperandKind;
+    const void *Operand;
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tbaederr wrote:

Can you document what `Operand` can point to? It seems like right now only a `TypeSourceInfo` is possible; can we also use a pointer union similar to `ReflectExpr::operand_type` here?

https://github.com/llvm/llvm-project/pull/190356