[clang] [clang] Add bitint classification for __builtin_classify_type (PR #72036)

[Aaron Ballman via cfe-commits]

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@@ -11486,6 +11486,7 @@ bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
 
 /// Values returned by __builtin_classify_type, chosen to match the values
 /// produced by GCC's builtin.
+/// The values can be found in gcc/typeclass.h in the GCC repository.
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AaronBallman wrote:

```suggestion

```
For licensing clarity, I don't think we want to encourage people to go look at the source of GCC even though this is a helpful comment.

https://github.com/llvm/llvm-project/pull/72036