[clang] [BoundsSafety][Sema] Allow counted_by and counted_by_or_null on pointers where the pointee type is incomplete but potentially completable (PR #106321)

[Aaron Ballman via cfe-commits]

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@@ -3907,6 +3923,31 @@ CountAttributedType::CountAttributedType(
     DeclSlot[i] = CoupledDecls[i];
 }
 
+StringRef CountAttributedType::getAttributeName(bool WithMacroPrefix) const {
+// TODO: This method isn't really ideal because it doesn't return the spelling
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AaronBallman wrote:

It's not clear to me why this is needed at all -- doesn't `Attr::getSpelling()` suffice on the attribute, rather than asking the type?

https://github.com/llvm/llvm-project/pull/106321