[clang] [BoundsSafety] Support late parsing for `counted_by` in type positions (PR #166491)

[Hans Wennborg via cfe-commits]

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@@ -1238,6 +1238,9 @@ struct DeclaratorChunk {
 
   ParsedAttributesView AttrList;
 
+  using LateAttrListTy = SmallVector<void *, 1>;
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zmodem wrote:

I see. Forward declaring it would have been nice, but that sounds very tricky. Maybe just adding a comment explaining what `void*` refers to is good enough?

https://github.com/llvm/llvm-project/pull/166491