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

[Yeoul Na via cfe-commits]

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@@ -102,111 +102,83 @@ struct on_pointer_anon_count {
 //==============================================================================
 // __sized_by_or_null on struct member pointer in type attribute position
 //==============================================================================
-// TODO: Correctly parse sized_by_or_null as a type attribute. Currently it is parsed
-// as a declaration attribute and is **not** late parsed resulting in the `size`
-// field being unavailable.
 
 struct on_member_pointer_complete_ty_ty_pos {
-  // TODO: Allow this
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   struct size_known *__sized_by_or_null(size) buf;
   int size;
 };
 
 struct on_member_pointer_incomplete_ty_ty_pos {
-  // TODO: Allow this
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   struct size_unknown * __sized_by_or_null(size) buf;
   int size;
 };
 
 struct on_member_pointer_const_incomplete_ty_ty_pos {
-  // TODO: Allow this
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   const struct size_unknown * __sized_by_or_null(size) buf;
   int size;
 };
 
 struct on_member_pointer_void_ty_ty_pos {
-  // TODO: This should fail because the attribute is
-  // on a pointer with the pointee being an incomplete type.
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   void *__sized_by_or_null(size) buf;
   int size;
 };
 
 // -
 
 struct on_member_pointer_fn_ptr_ty_pos {
-  // TODO: buffer of `size` function pointers should be allowed
-  // but fails because this isn't late parsed.
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   void (** __sized_by_or_null(size) fn_ptr)(void);
   int size;
 };
 
 struct on_member_pointer_fn_ptr_ty_ptr_ty_pos {
-  // TODO: buffer of `size` function pointers should be allowed
-  // but fails because this isn't late parsed.
-  // expected-error at +1{{use of undeclared identifier 'size'}}
   fn_ptr_ty* __sized_by_or_null(size) fn_ptr;
   int size;
 };
 
 struct on_member_pointer_fn_ty_ty_pos {
-  // TODO: This should fail because the attribute is
-  // on a pointer with the pointee being a function type.
-  // expected-error at +1{{use of undeclared identifier 'size'}}
+  // expected-error at +1{{'sized_by_or_null' cannot be applied to a pointer with pointee of unknown size because 'void (void)' is a function type}}
----------------
rapidsna wrote:

Created an issue to track it https://github.com/llvm/llvm-project/issues/167368

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