Fix dyn* trait resolution

Author: eholk

compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs

@@ -384,7 +384,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         if self.tcx().trait_is_auto(def_id) {
             match self_ty.kind() {
-                ty::Dynamic(..) => {
+                ty::Dynamic(..) | ty::DynStar(..) => {
                     // For object types, we don't know what the closed
                     // over types are. This means we conservatively
                     // say nothing; a candidate may be added by
@@ -453,7 +453,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             // any LBR.
             let self_ty = self.tcx().erase_late_bound_regions(obligation.self_ty());
             let poly_trait_ref = match self_ty.kind() {
-                ty::Dynamic(ref data, ..) => {
+                ty::Dynamic(ref data, ..) | ty::DynStar(ref data, ..) => {
                     if data.auto_traits().any(|did| did == obligation.predicate.def_id()) {
                         debug!(
                             "assemble_candidates_from_object_ty: matched builtin bound, \
@@ -548,7 +548,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             .ty()
             .unwrap();
 
-            if let ty::Dynamic(data, ..) = ty.kind() { data.principal() } else { None }
+            if let ty::Dynamic(data, ..) | ty::DynStar(data, ..) = ty.kind() {
+                data.principal()
+            } else {
+                None
+            }
         })
     }
 

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -430,7 +430,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         let trait_predicate = self.infcx.instantiate_binder_with_placeholders(obligation.predicate);
         let self_ty = self.infcx.shallow_resolve(trait_predicate.self_ty());
         let obligation_trait_ref = ty::Binder::dummy(trait_predicate.trait_ref);
-        let ty::Dynamic(data, ..) = *self_ty.kind() else {
+        let (ty::Dynamic(data, ..) | ty::DynStar(data, ..)) = *self_ty.kind() else {
             span_bug!(obligation.cause.span, "object candidate with non-object");
         };