Plumb dyn trait representation through ty::Dynamic

compiler/rustc_codegen_ssa/src/meth.rs

@@ -69,7 +69,7 @@ impl<'a, 'tcx> VirtualIndex {
 fn expect_dyn_trait_in_self<'tcx>(ty: Ty<'tcx>) -> ty::PolyExistentialTraitRef<'tcx> {
     for arg in ty.peel_refs().walk() {
         if let GenericArgKind::Type(ty) = arg.unpack() {
-            if let ty::Dynamic(data, _) = ty.kind() {
+            if let ty::Dynamic(data, _, _) = ty.kind() {
                 return data.principal().expect("expected principal trait object");
             }
         }

compiler/rustc_const_eval/src/interpret/cast.rs

@@ -312,7 +312,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let new_vptr = self.get_vtable_ptr(ty, data_b.principal())?;
                 self.write_immediate(Immediate::new_dyn_trait(old_data, new_vptr, self), dest)
             }
-            (_, &ty::Dynamic(ref data, _)) => {
+            (_, &ty::Dynamic(ref data, _, _repr)) => {
                 // Initial cast from sized to dyn trait
                 let vtable = self.get_vtable_ptr(src_pointee_ty, data.principal())?;
                 let ptr = self.read_scalar(src)?;

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -95,7 +95,7 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>(
             | ty::Ref(_, _, _)
             | ty::FnDef(_, _)
             | ty::FnPtr(_)
-            | ty::Dynamic(_, _)
+            | ty::Dynamic(_, _, _)
             | ty::Closure(_, _)
             | ty::Generator(_, _, _)
             | ty::GeneratorWitness(_)

compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs

@@ -48,7 +48,7 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
             | ty::FnPtr(_)
             | ty::Never
             | ty::Tuple(_)
-            | ty::Dynamic(_, _) => self.pretty_print_type(ty),
+            | ty::Dynamic(_, _, _) => self.pretty_print_type(ty),
 
             // Placeholders (all printed as `_` to uniformize them).
             ty::Param(_) | ty::Bound(..) | ty::Placeholder(_) | ty::Infer(_) | ty::Error(_) => {

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs

@@ -544,7 +544,7 @@ pub struct TraitObjectVisitor(pub FxHashSet<DefId>);
 impl<'tcx> TypeVisitor<'tcx> for TraitObjectVisitor {
     fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
         match t.kind() {
-            ty::Dynamic(preds, re) if re.is_static() => {
+            ty::Dynamic(preds, re, _) if re.is_static() => {
                 if let Some(def_id) = preds.principal_def_id() {
                     self.0.insert(def_id);
                 }

compiler/rustc_lint/src/unused.rs

@@ -222,7 +222,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
                     }
                     has_emitted
                 }
-                ty::Dynamic(binder, _) => {
+                ty::Dynamic(binder, _, _) => {
                     let mut has_emitted = false;
                     for predicate in binder.iter() {
                         if let ty::ExistentialPredicate::Trait(ref trait_ref) =

compiler/rustc_middle/src/ty/context.rs

@@ -63,7 +63,9 @@ use rustc_span::{Span, DUMMY_SP};
 use rustc_target::abi::{Layout, LayoutS, TargetDataLayout, VariantIdx};
 use rustc_target::spec::abi;
 use rustc_type_ir::sty::TyKind::*;
-use rustc_type_ir::{InternAs, InternIteratorElement, Interner, TypeFlags};
+use rustc_type_ir::{
+    InternAs, InternIteratorElement, Interner, TraitObjectRepresentation, TypeFlags,
+};
 
 use std::any::Any;
 use std::borrow::Borrow;
@@ -2545,8 +2547,9 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         obj: &'tcx List<ty::Binder<'tcx, ExistentialPredicate<'tcx>>>,
         reg: ty::Region<'tcx>,
+        repr: TraitObjectRepresentation,
     ) -> Ty<'tcx> {
-        self.mk_ty(Dynamic(obj, reg))
+        self.mk_ty(Dynamic(obj, reg, repr))
     }
 
     #[inline]

compiler/rustc_middle/src/ty/diagnostics.rs

@@ -467,7 +467,7 @@ impl<'tcx> TypeVisitor<'tcx> for IsSuggestableVisitor<'tcx> {
                 }
             }
 
-            Dynamic(dty, _) => {
+            Dynamic(dty, _, _) => {
                 for pred in *dty {
                     match pred.skip_binder() {
                         ExistentialPredicate::Trait(_) | ExistentialPredicate::Projection(_) => {

compiler/rustc_middle/src/ty/flags.rs

@@ -171,7 +171,7 @@ impl FlagComputation {
                 self.add_substs(substs);
             }
 
-            &ty::Dynamic(obj, r) => {
+            &ty::Dynamic(obj, r, _) => {
                 for predicate in obj.iter() {
                     self.bound_computation(predicate, |computation, predicate| match predicate {
                         ty::ExistentialPredicate::Trait(tr) => computation.add_substs(tr.substs),

compiler/rustc_middle/src/ty/layout.rs

@@ -2464,7 +2464,8 @@ where
 
                     match tcx.struct_tail_erasing_lifetimes(pointee, cx.param_env()).kind() {
                         ty::Slice(_) | ty::Str => TyMaybeWithLayout::Ty(tcx.types.usize),
-                        ty::Dynamic(_, _) => {
+                        // FIXME(eholk): Do the right thing with trait object representation
+                        ty::Dynamic(_, _, _repr) => {
                             TyMaybeWithLayout::Ty(tcx.mk_imm_ref(
                                 tcx.lifetimes.re_static,
                                 tcx.mk_array(tcx.types.usize, 3),

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -16,6 +16,7 @@ use rustc_session::cstore::{ExternCrate, ExternCrateSource};
 use rustc_span::symbol::{kw, Ident, Symbol};
 use rustc_target::abi::Size;
 use rustc_target::spec::abi::Abi;
+use rustc_type_ir::TraitObjectRepresentation;
 
 use std::cell::Cell;
 use std::char;
@@ -619,12 +620,16 @@ pub trait PrettyPrinter<'tcx>:
             ty::Adt(def, substs) => {
                 p!(print_def_path(def.did(), substs));
             }
-            ty::Dynamic(data, r) => {
+            ty::Dynamic(data, r, repr) => {
                 let print_r = self.should_print_region(r);
                 if print_r {
                     p!("(");
                 }
-                p!("dyn ", print(data));
+                match repr {
+                    TraitObjectRepresentation::Unsized => p!("dyn "),
+                    TraitObjectRepresentation::Sized => p!("dyn* "),
+                }
+                p!(print(data));
                 if print_r {
                     p!(" + ", print(r), ")");
                 }

compiler/rustc_middle/src/ty/relate.rs

@@ -441,7 +441,9 @@ pub fn super_relate_tys<'tcx, R: TypeRelation<'tcx>>(
 
         (&ty::Foreign(a_id), &ty::Foreign(b_id)) if a_id == b_id => Ok(tcx.mk_foreign(a_id)),
 
-        (&ty::Dynamic(a_obj, a_region), &ty::Dynamic(b_obj, b_region)) => {
+        (&ty::Dynamic(a_obj, a_region, a_repr), &ty::Dynamic(b_obj, b_region, b_repr))
+            if a_repr == b_repr =>
+        {
             let region_bound = relation.with_cause(Cause::ExistentialRegionBound, |relation| {
                 relation.relate_with_variance(
                     ty::Contravariant,
@@ -450,7 +452,7 @@ pub fn super_relate_tys<'tcx, R: TypeRelation<'tcx>>(
                     b_region,
                 )
             })?;
-            Ok(tcx.mk_dynamic(relation.relate(a_obj, b_obj)?, region_bound))
+            Ok(tcx.mk_dynamic(relation.relate(a_obj, b_obj)?, region_bound, a_repr))
         }
 
         (&ty::Generator(a_id, a_substs, movability), &ty::Generator(b_id, b_substs, _))

compiler/rustc_middle/src/ty/structural_impls.rs

@@ -1014,9 +1014,11 @@ impl<'tcx> TypeSuperFoldable<'tcx> for Ty<'tcx> {
             ty::Array(typ, sz) => ty::Array(typ.try_fold_with(folder)?, sz.try_fold_with(folder)?),
             ty::Slice(typ) => ty::Slice(typ.try_fold_with(folder)?),
             ty::Adt(tid, substs) => ty::Adt(tid, substs.try_fold_with(folder)?),
-            ty::Dynamic(trait_ty, region) => {
+            ty::Dynamic(trait_ty, region, representation) => ty::Dynamic(
-                ty::Dynamic(trait_ty.try_fold_with(folder)?, region.try_fold_with(folder)?)
+                trait_ty.try_fold_with(folder)?,
-            }
+                region.try_fold_with(folder)?,
+                representation,
+            ),
             ty::Tuple(ts) => ty::Tuple(ts.try_fold_with(folder)?),
             ty::FnDef(def_id, substs) => ty::FnDef(def_id, substs.try_fold_with(folder)?),
             ty::FnPtr(f) => ty::FnPtr(f.try_fold_with(folder)?),
@@ -1060,7 +1062,7 @@ impl<'tcx> TypeSuperVisitable<'tcx> for Ty<'tcx> {
             }
             ty::Slice(typ) => typ.visit_with(visitor),
             ty::Adt(_, substs) => substs.visit_with(visitor),
-            ty::Dynamic(ref trait_ty, ref reg) => {
+            ty::Dynamic(ref trait_ty, ref reg, _) => {
                 trait_ty.visit_with(visitor)?;
                 reg.visit_with(visitor)
             }

compiler/rustc_middle/src/ty/walk.rs

@@ -152,7 +152,7 @@ fn push_inner<'tcx>(stack: &mut TypeWalkerStack<'tcx>, parent: GenericArg<'tcx>)
             ty::Projection(data) => {
                 stack.extend(data.substs.iter().rev());
             }
-            ty::Dynamic(obj, lt) => {
+            ty::Dynamic(obj, lt, _) => {
                 stack.push(lt.into());
                 stack.extend(obj.iter().rev().flat_map(|predicate| {
                     let (substs, opt_ty) = match predicate.skip_binder() {

compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs

@@ -627,7 +627,7 @@ fn encode_ty<'tcx>(
         }
 
         // Trait types
-        ty::Dynamic(predicates, region) => {
+        ty::Dynamic(predicates, region, _repr) => {
             // u3dynI<element-type1[..element-typeN]>E, where <element-type> is <predicate>, as
             // vendor extended type.
             let mut s = String::from("u3dynI");

compiler/rustc_symbol_mangling/src/v0.rs

@@ -479,7 +479,7 @@ impl<'tcx> Printer<'tcx> for &mut SymbolMangler<'tcx> {
                 })?;
             }
 
-            ty::Dynamic(predicates, r) => {
+            ty::Dynamic(predicates, r, _repr) => {
                 self.push("D");
                 self = self.print_dyn_existential(predicates)?;
                 self = r.print(self)?;

compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs

@@ -256,7 +256,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                     }
                 }
             }
-            if let ty::Dynamic(traits, _) = self_ty.kind() {
+            if let ty::Dynamic(traits, _, _) = self_ty.kind() {
                 for t in traits.iter() {
                     if let ty::ExistentialPredicate::Trait(trait_ref) = t.skip_binder() {
                         flags.push((sym::_Self, Some(self.tcx.def_path_str(trait_ref.def_id))))

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -1067,7 +1067,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         self_ty: Ty<'tcx>,
         object_ty: Ty<'tcx>,
     ) {
-        let ty::Dynamic(predicates, _) = object_ty.kind() else { return; };
+        let ty::Dynamic(predicates, _, _) = object_ty.kind() else { return; };
         let self_ref_ty = self.tcx.mk_imm_ref(self.tcx.lifetimes.re_erased, self_ty);
 
         for predicate in predicates.iter() {
@@ -1365,7 +1365,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         let trait_pred = self.resolve_vars_if_possible(trait_pred);
         let ty = trait_pred.skip_binder().self_ty();
         let is_object_safe = match ty.kind() {
-            ty::Dynamic(predicates, _) => {
+            ty::Dynamic(predicates, _, _) => {
                 // If the `dyn Trait` is not object safe, do not suggest `Box<dyn Trait>`.
                 predicates
                     .principal_def_id()
@@ -1425,7 +1425,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         let mut spans_and_needs_box = vec![];
 
         match liberated_sig.output().kind() {
-            ty::Dynamic(predicates, _) => {
+            ty::Dynamic(predicates, _, _) => {
                 let cause = ObligationCause::misc(ret_ty.span, fn_hir_id);
                 let param_env = ty::ParamEnv::empty();
 

compiler/rustc_trait_selection/src/traits/object_safety.rs

@@ -21,6 +21,7 @@ use rustc_middle::ty::abstract_const::{walk_abstract_const, AbstractConst};
 use rustc_middle::ty::subst::{GenericArg, InternalSubsts, Subst};
 use rustc_middle::ty::{
     self, EarlyBinder, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor,
+    TraitObjectRepresentation,
 };
 use rustc_middle::ty::{Predicate, ToPredicate};
 use rustc_session::lint::builtin::WHERE_CLAUSES_OBJECT_SAFETY;
@@ -600,7 +601,8 @@ fn object_ty_for_trait<'tcx>(
     let existential_predicates = tcx
         .mk_poly_existential_predicates(iter::once(trait_predicate).chain(projection_predicates));
 
-    let object_ty = tcx.mk_dynamic(existential_predicates, lifetime);
+    let object_ty =
+        tcx.mk_dynamic(existential_predicates, lifetime, TraitObjectRepresentation::Unsized);
 
     debug!("object_ty_for_trait: object_ty=`{}`", object_ty);
 

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

@@ -784,7 +784,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         let upcast_trait_ref;
         match (source.kind(), target.kind()) {
             // TraitA+Kx+'a -> TraitB+Ky+'b (trait upcasting coercion).
-            (&ty::Dynamic(ref data_a, r_a), &ty::Dynamic(ref data_b, r_b)) => {
+            (&ty::Dynamic(ref data_a, r_a, repr_a), &ty::Dynamic(ref data_b, r_b, repr_b))
+                if repr_a == repr_b =>
+            {
                 // See `assemble_candidates_for_unsizing` for more info.
                 // We already checked the compatibility of auto traits within `assemble_candidates_for_unsizing`.
                 let principal_a = data_a.principal().unwrap();
@@ -810,7 +812,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                             .map(ty::Binder::dummy),
                     );
                 let existential_predicates = tcx.mk_poly_existential_predicates(iter);
-                let source_trait = tcx.mk_dynamic(existential_predicates, r_b);
+                let source_trait = tcx.mk_dynamic(existential_predicates, r_b, repr_b);
 
                 // Require that the traits involved in this upcast are **equal**;
                 // only the **lifetime bound** is changed.
@@ -888,7 +890,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         let mut nested = vec![];
         match (source.kind(), target.kind()) {
             // Trait+Kx+'a -> Trait+Ky+'b (auto traits and lifetime subtyping).
-            (&ty::Dynamic(ref data_a, r_a), &ty::Dynamic(ref data_b, r_b)) => {
+            (&ty::Dynamic(ref data_a, r_a, repr_a), &ty::Dynamic(ref data_b, r_b, repr_b))
+                if repr_a == repr_b =>
+            {
                 // See `assemble_candidates_for_unsizing` for more info.
                 // We already checked the compatibility of auto traits within `assemble_candidates_for_unsizing`.
                 let iter = data_a
@@ -907,7 +911,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                             .map(ty::Binder::dummy),
                     );
                 let existential_predicates = tcx.mk_poly_existential_predicates(iter);
-                let source_trait = tcx.mk_dynamic(existential_predicates, r_b);
+                let source_trait = tcx.mk_dynamic(existential_predicates, r_b, repr_b);
 
                 // Require that the traits involved in this upcast are **equal**;
                 // only the **lifetime bound** is changed.
@@ -934,7 +938,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             }
 
             // `T` -> `Trait`
-            (_, &ty::Dynamic(ref data, r)) => {
+            (_, &ty::Dynamic(ref data, r, _repr)) => {
                 let mut object_dids = data.auto_traits().chain(data.principal_def_id());
                 if let Some(did) = object_dids.find(|did| !tcx.is_object_safe(*did)) {
                     return Err(TraitNotObjectSafe(did));

compiler/rustc_trait_selection/src/traits/wf.rs

@@ -639,7 +639,7 @@ impl<'tcx> WfPredicates<'tcx> {
                     }
                 }
 
-                ty::Dynamic(data, r) => {
+                ty::Dynamic(data, r, _) => {
                     // WfObject
                     //
                     // Here, we defer WF checking due to higher-ranked

compiler/rustc_traits/src/chalk/lowering.rs

@@ -326,7 +326,7 @@ impl<'tcx> LowerInto<'tcx, chalk_ir::Ty<RustInterner<'tcx>>> for Ty<'tcx> {
                     )),
                 })
             }
-            ty::Dynamic(predicates, region) => chalk_ir::TyKind::Dyn(chalk_ir::DynTy {
+            ty::Dynamic(predicates, region, _repr) => chalk_ir::TyKind::Dyn(chalk_ir::DynTy {
                 bounds: predicates.lower_into(interner),
                 lifetime: region.lower_into(interner),
             }),

compiler/rustc_ty_utils/src/ty.rs

@@ -389,7 +389,7 @@ fn issue33140_self_ty(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Ty<'_>> {
 
     let self_ty = trait_ref.self_ty();
     let self_ty_matches = match self_ty.kind() {
-        ty::Dynamic(ref data, re) if re.is_static() => data.principal().is_none(),
+        ty::Dynamic(ref data, re, _) if re.is_static() => data.principal().is_none(),
         _ => false,
     };
 

compiler/rustc_type_ir/src/sty.rs

@@ -18,6 +18,27 @@ use self::TyKind::*;
 use rustc_data_structures::stable_hasher::HashStable;
 use rustc_serialize::{Decodable, Decoder, Encodable};
 
+/// Specifies how a trait object is represented.
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Encodable, Decodable)]
+pub enum TraitObjectRepresentation {
+    /// An unsized `dyn Trait` object
+    Unsized,
+    /// A sized `dyn* Trait` object
+    Sized,
+}
+
+// Manually implemented because deriving HashStable requires rustc_query_system, which would
+// create a cyclic dependency.
+impl<CTX> HashStable<CTX> for TraitObjectRepresentation {
+    fn hash_stable(
+        &self,
+        hcx: &mut CTX,
+        hasher: &mut rustc_data_structures::stable_hasher::StableHasher,
+    ) {
+        std::mem::discriminant(self).hash_stable(hcx, hasher);
+    }
+}
+
 /// Defines the kinds of types used by the type system.
 ///
 /// Types written by the user start out as `hir::TyKind` and get
@@ -95,7 +116,7 @@ pub enum TyKind<I: Interner> {
     FnPtr(I::PolyFnSig),
 
     /// A trait object. Written as `dyn for<'b> Trait<'b, Assoc = u32> + Send + 'a`.
-    Dynamic(I::ListBinderExistentialPredicate, I::Region),
+    Dynamic(I::ListBinderExistentialPredicate, I::Region, TraitObjectRepresentation),
 
     /// The anonymous type of a closure. Used to represent the type of `|a| a`.
     ///
@@ -218,7 +239,7 @@ const fn tykind_discriminant<I: Interner>(value: &TyKind<I>) -> usize {
         Ref(_, _, _) => 11,
         FnDef(_, _) => 12,
         FnPtr(_) => 13,
-        Dynamic(_, _) => 14,
+        Dynamic(..) => 14,
         Closure(_, _) => 15,
         Generator(_, _, _) => 16,
         GeneratorWitness(_) => 17,
@@ -252,7 +273,7 @@ impl<I: Interner> Clone for TyKind<I> {
             Ref(r, t, m) => Ref(r.clone(), t.clone(), m.clone()),
             FnDef(d, s) => FnDef(d.clone(), s.clone()),
             FnPtr(s) => FnPtr(s.clone()),
-            Dynamic(p, r) => Dynamic(p.clone(), r.clone()),
+            Dynamic(p, r, repr) => Dynamic(p.clone(), r.clone(), repr.clone()),
             Closure(d, s) => Closure(d.clone(), s.clone()),
             Generator(d, s, m) => Generator(d.clone(), s.clone(), m.clone()),
             GeneratorWitness(g) => GeneratorWitness(g.clone()),
@@ -297,9 +318,10 @@ impl<I: Interner> PartialEq for TyKind<I> {
                     __self_0 == __arg_1_0 && __self_1 == __arg_1_1
                 }
                 (&FnPtr(ref __self_0), &FnPtr(ref __arg_1_0)) => __self_0 == __arg_1_0,
-                (&Dynamic(ref __self_0, ref __self_1), &Dynamic(ref __arg_1_0, ref __arg_1_1)) => {
+                (
-                    __self_0 == __arg_1_0 && __self_1 == __arg_1_1
+                    &Dynamic(ref __self_0, ref __self_1, ref self_repr),
-                }
+                    &Dynamic(ref __arg_1_0, ref __arg_1_1, ref arg_repr),
+                ) => __self_0 == __arg_1_0 && __self_1 == __arg_1_1 && self_repr == arg_repr,
                 (&Closure(ref __self_0, ref __self_1), &Closure(ref __arg_1_0, ref __arg_1_1)) => {
                     __self_0 == __arg_1_0 && __self_1 == __arg_1_1
                 }
@@ -384,12 +406,16 @@ impl<I: Interner> Ord for TyKind<I> {
                     }
                 }
                 (&FnPtr(ref __self_0), &FnPtr(ref __arg_1_0)) => Ord::cmp(__self_0, __arg_1_0),
-                (&Dynamic(ref __self_0, ref __self_1), &Dynamic(ref __arg_1_0, ref __arg_1_1)) => {
+                (
-                    match Ord::cmp(__self_0, __arg_1_0) {
+                    &Dynamic(ref __self_0, ref __self_1, ref self_repr),
-                        Ordering::Equal => Ord::cmp(__self_1, __arg_1_1),
+                    &Dynamic(ref __arg_1_0, ref __arg_1_1, ref arg_repr),
+                ) => match Ord::cmp(__self_0, __arg_1_0) {
+                    Ordering::Equal => match Ord::cmp(__self_1, __arg_1_1) {
+                        Ordering::Equal => Ord::cmp(self_repr, arg_repr),
                         cmp => cmp,
-                    }
+                    },
-                }
+                    cmp => cmp,
+                },
                 (&Closure(ref __self_0, ref __self_1), &Closure(ref __arg_1_0, ref __arg_1_1)) => {
                     match Ord::cmp(__self_0, __arg_1_0) {
                         Ordering::Equal => Ord::cmp(__self_1, __arg_1_1),
@@ -492,10 +518,11 @@ impl<I: Interner> hash::Hash for TyKind<I> {
                 hash::Hash::hash(&tykind_discriminant(self), state);
                 hash::Hash::hash(__self_0, state)
             }
-            (&Dynamic(ref __self_0, ref __self_1),) => {
+            (&Dynamic(ref __self_0, ref __self_1, ref repr),) => {
                 hash::Hash::hash(&tykind_discriminant(self), state);
                 hash::Hash::hash(__self_0, state);
-                hash::Hash::hash(__self_1, state)
+                hash::Hash::hash(__self_1, state);
+                hash::Hash::hash(repr, state)
             }
             (&Closure(ref __self_0, ref __self_1),) => {
                 hash::Hash::hash(&tykind_discriminant(self), state);
@@ -570,7 +597,7 @@ impl<I: Interner> fmt::Debug for TyKind<I> {
             Ref(f0, f1, f2) => Formatter::debug_tuple_field3_finish(f, "Ref", f0, f1, f2),
             FnDef(f0, f1) => Formatter::debug_tuple_field2_finish(f, "FnDef", f0, f1),
             FnPtr(f0) => Formatter::debug_tuple_field1_finish(f, "FnPtr", f0),
-            Dynamic(f0, f1) => Formatter::debug_tuple_field2_finish(f, "Dynamic", f0, f1),
+            Dynamic(f0, f1, f2) => Formatter::debug_tuple_field3_finish(f, "Dynamic", f0, f1, f2),
             Closure(f0, f1) => Formatter::debug_tuple_field2_finish(f, "Closure", f0, f1),
             Generator(f0, f1, f2) => {
                 Formatter::debug_tuple_field3_finish(f, "Generator", f0, f1, f2)
@@ -659,9 +686,10 @@ where
             FnPtr(polyfnsig) => e.emit_enum_variant(disc, |e| {
                 polyfnsig.encode(e);
             }),
-            Dynamic(l, r) => e.emit_enum_variant(disc, |e| {
+            Dynamic(l, r, repr) => e.emit_enum_variant(disc, |e| {
                 l.encode(e);
                 r.encode(e);
+                repr.encode(e);
             }),
             Closure(def_id, substs) => e.emit_enum_variant(disc, |e| {
                 def_id.encode(e);
@@ -748,7 +776,7 @@ where
             11 => Ref(Decodable::decode(d), Decodable::decode(d), Decodable::decode(d)),
             12 => FnDef(Decodable::decode(d), Decodable::decode(d)),
             13 => FnPtr(Decodable::decode(d)),
-            14 => Dynamic(Decodable::decode(d), Decodable::decode(d)),
+            14 => Dynamic(Decodable::decode(d), Decodable::decode(d), Decodable::decode(d)),
             15 => Closure(Decodable::decode(d), Decodable::decode(d)),
             16 => Generator(Decodable::decode(d), Decodable::decode(d), Decodable::decode(d)),
             17 => GeneratorWitness(Decodable::decode(d)),
@@ -845,9 +873,10 @@ where
             FnPtr(polyfnsig) => {
                 polyfnsig.hash_stable(__hcx, __hasher);
             }
-            Dynamic(l, r) => {
+            Dynamic(l, r, repr) => {
                 l.hash_stable(__hcx, __hasher);
                 r.hash_stable(__hcx, __hasher);
+                repr.hash_stable(__hcx, __hasher);
             }
             Closure(def_id, substs) => {
                 def_id.hash_stable(__hcx, __hasher);

compiler/rustc_typeck/src/astconv/mod.rs

@@ -31,6 +31,7 @@ use rustc_middle::ty::GenericParamDefKind;
 use rustc_middle::ty::{
     self, Const, DefIdTree, EarlyBinder, IsSuggestable, Ty, TyCtxt, TypeVisitable,
 };
+use rustc_middle::ty::{TraitObjectRepresentation};
 use rustc_session::lint::builtin::{AMBIGUOUS_ASSOCIATED_ITEMS, BARE_TRAIT_OBJECTS};
 use rustc_span::edition::Edition;
 use rustc_span::lev_distance::find_best_match_for_name;
@@ -1572,7 +1573,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         };
         debug!("region_bound: {:?}", region_bound);
 
-        let ty = tcx.mk_dynamic(existential_predicates, region_bound);
+        let ty = tcx.mk_dynamic(
+            existential_predicates,
+            region_bound,
+            TraitObjectRepresentation::Unsized, // FIXME: check whether the source syntax was dyn or dyn*
+        );
         debug!("trait_object_type: {:?}", ty);
         ty
     }

compiler/rustc_typeck/src/check/generator_interior.rs

@@ -527,7 +527,7 @@ fn check_must_not_suspend_ty<'tcx>(
             }
             has_emitted
         }
-        ty::Dynamic(binder, _) => {
+        ty::Dynamic(binder, _, _) => {
             let mut has_emitted = false;
             for predicate in binder.iter() {
                 if let ty::ExistentialPredicate::Trait(ref trait_ref) = predicate.skip_binder() {

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -537,7 +537,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 bound_spans.push((self.tcx.def_span(def.did()), msg))
                             }
                             // Point at the trait object that couldn't satisfy the bound.
-                            ty::Dynamic(preds, _) => {
+                            ty::Dynamic(preds, _, _) => {
                                 for pred in preds.iter() {
                                     match pred.skip_binder() {
                                         ty::ExistentialPredicate::Trait(tr) => bound_spans

compiler/rustc_typeck/src/variance/constraints.rs

@@ -257,7 +257,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                 self.add_constraints_from_invariant_substs(current, substs, variance);
             }
 
-            ty::Dynamic(data, r) => {
+            ty::Dynamic(data, r, _) => {
                 // The type `Foo<T+'a>` is contravariant w/r/t `'a`:
                 let contra = self.contravariant(variance);
                 self.add_constraints_from_region(current, r, contra);

src/librustdoc/clean/mod.rs

@@ -1600,7 +1600,7 @@ pub(crate) fn clean_middle_ty<'tcx>(
             let path = external_path(cx, did, false, ThinVec::new(), InternalSubsts::empty());
             Type::Path { path }
         }
-        ty::Dynamic(obj, ref reg) => {
+        ty::Dynamic(obj, ref reg, _) => {
             // HACK: pick the first `did` as the `did` of the trait object. Someone
             // might want to implement "native" support for marker-trait-only
             // trait objects.