[clang] [Clang] Add __builtin_counted_by_ref builtin (PR #114495)

[Bill Wendling via cfe-commits]

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@@ -4914,3 +4914,9 @@ def ArithmeticFence : LangBuiltin<"ALL_LANGUAGES"> {
   let Attributes = [CustomTypeChecking, Constexpr];
   let Prototype = "void(...)";
 }
+
+def CountedByRef : Builtin {
+  let Spellings = ["__builtin_counted_by_ref"];
+  let Attributes = [NoThrow, CustomTypeChecking];
+  let Prototype = "int(...)";
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bwendling wrote:

For a custom type checking, the prototype is basically meaningless. I'd rather not mess with this as it's not very important.

https://github.com/llvm/llvm-project/pull/114495