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

[Vlad Serebrennikov via cfe-commits]

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@@ -2099,6 +2099,70 @@ class Sema final : public SemaBase {
   bool CheckCountedByAttrOnField(FieldDecl *FD, Expr *E, bool CountInBytes,
                                  bool OrNull);
 
+  // AssignmentAction - This is used by all the assignment diagnostic functions
+  // to represent what is actually causing the operation
+  enum AssignmentAction {
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Endilll wrote:

Ideally you should turn it into scoped enum and move it outside of `Sema` definition in a separate NFC patch, then update this PR with those changes.

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