Implement lint against direct uses of rustc_type_ir in compiler crates

This commit adds a lint to prevent the use of rustc_type_ir in random
compiler crates, except for type system internals traits, which are
explicitly allowed. Moreover, this fixes diagnostic_items() to include
the CRATE_OWNER_ID, otherwise rustc_diagnostic_item attribute is ignored
on the crate root.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/rustc_passes/src/diagnostic_items.rs b/compiler/rustc_passes/src/diagnostic_items.rs
index 17a729f422a..8f572af02c2 100644
--- a/compiler/rustc_passes/src/diagnostic_items.rs
+++ b/compiler/rustc_passes/src/diagnostic_items.rs
@@ -10,7 +10,7 @@
 //! * Compiler internal types like `Ty` and `TyCtxt`
 
 use rustc_hir::diagnostic_items::DiagnosticItems;
-use rustc_hir::{Attribute, OwnerId};
+use rustc_hir::{Attribute, CRATE_OWNER_ID, OwnerId};
 use rustc_middle::query::{LocalCrate, Providers};
 use rustc_middle::ty::TyCtxt;
 use rustc_span::def_id::{DefId, LOCAL_CRATE};
@@ -67,7 +67,7 @@ fn diagnostic_items(tcx: TyCtxt<'_>, _: LocalCrate) -> DiagnosticItems {
 
     // Collect diagnostic items in this crate.
     let crate_items = tcx.hir_crate_items(());
-    for id in crate_items.owners() {
+    for id in crate_items.owners().chain(std::iter::once(CRATE_OWNER_ID)) {
         observe_item(tcx, &mut diagnostic_items, id);
     }