Auto merge of #129244 - cjgillot:opaque-hir, r=compiler-errors

Make opaque types regular HIR nodes

Having opaque types as HIR owner introduces all sorts of complications. This PR proposes to make them regular HIR nodes instead.

I haven't gone through all the test changes yet, so there may be a few surprises.

Many thanks to `@camelid` for the first draft.
Fixes https://github.com/rust-lang/rust/issues/129023

Fixes #129099
Fixes #125843
Fixes #119716
Fixes #121422

4 files changed, 8 insertions, 8 deletions

diff --git a/compiler/rustc_lint/src/async_fn_in_trait.rs b/compiler/rustc_lint/src/async_fn_in_trait.rs
index d9040207300..63a8a949e96 100644
--- a/compiler/rustc_lint/src/async_fn_in_trait.rs
+++ b/compiler/rustc_lint/src/async_fn_in_trait.rs
@@ -104,8 +104,9 @@ impl<'tcx> LateLintPass<'tcx> for AsyncFnInTrait {
                 return;
             }
 
-            let hir::FnRetTy::Return(hir::Ty { kind: hir::TyKind::OpaqueDef(def, ..), .. }) =
-                sig.decl.output
+            let hir::FnRetTy::Return(hir::Ty {
+                kind: hir::TyKind::OpaqueDef(opaq_def, ..), ..
+            }) = sig.decl.output
             else {
                 // This should never happen, but let's not ICE.
                 return;
@@ -114,7 +115,7 @@ impl<'tcx> LateLintPass<'tcx> for AsyncFnInTrait {
                 cx.tcx,
                 sig,
                 body,
-                def.owner_id.def_id,
+                opaq_def.def_id,
                 " + Send",
             );
             cx.tcx.emit_node_span_lint(
diff --git a/compiler/rustc_lint/src/impl_trait_overcaptures.rs b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
index 5aeaad42069..d029ad93407 100644
--- a/compiler/rustc_lint/src/impl_trait_overcaptures.rs
+++ b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
@@ -258,7 +258,7 @@ where
             && self.seen.insert(opaque_def_id)
             // If it's owned by this function
             && let opaque =
-                self.tcx.hir_node_by_def_id(opaque_def_id).expect_item().expect_opaque_ty()
+                self.tcx.hir_node_by_def_id(opaque_def_id).expect_opaque_ty()
             && let hir::OpaqueTyOrigin::FnReturn { parent, .. } = opaque.origin
             && parent == self.parent_def_id
         {
diff --git a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
index 342ebfa0b06..ffbcf7f808e 100644
--- a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
+++ b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
@@ -68,8 +68,8 @@ declare_lint! {
 declare_lint_pass!(OpaqueHiddenInferredBound => [OPAQUE_HIDDEN_INFERRED_BOUND]);
 
 impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound {
-    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) {
-        let hir::ItemKind::OpaqueTy(opaque) = &item.kind else {
+    fn check_ty(&mut self, cx: &LateContext<'tcx>, ty: &'tcx hir::Ty<'tcx>) {
+        let hir::TyKind::OpaqueDef(opaque, _) = &ty.kind else {
             return;
         };
 
@@ -84,7 +84,7 @@ impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound {
             return;
         }
 
-        let def_id = item.owner_id.def_id.to_def_id();
+        let def_id = opaque.def_id.to_def_id();
         let infcx = &cx.tcx.infer_ctxt().build();
         // For every projection predicate in the opaque type's explicit bounds,
         // check that the type that we're assigning actually satisfies the bounds
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index 75611d71025..db4413149a4 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -1419,7 +1419,6 @@ impl<'tcx> LateLintPass<'tcx> for ImproperCTypesDefinitions {
             hir::ItemKind::Impl(..)
             | hir::ItemKind::TraitAlias(..)
             | hir::ItemKind::Trait(..)
-            | hir::ItemKind::OpaqueTy(..)
             | hir::ItemKind::GlobalAsm(..)
             | hir::ItemKind::ForeignMod { .. }
             | hir::ItemKind::Mod(..)