Typecheck dyn* coercions

Also changes things to treat dyn* as a sized type, unlike dyn Trait.

2 files changed, 4 insertions, 2 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/object_safety.rs b/compiler/rustc_trait_selection/src/traits/object_safety.rs
index f31dde044f9..43ee5b55455 100644
--- a/compiler/rustc_trait_selection/src/traits/object_safety.rs
+++ b/compiler/rustc_trait_selection/src/traits/object_safety.rs
@@ -20,8 +20,8 @@ use rustc_hir::def_id::DefId;
 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,
+    self, EarlyBinder, TraitObjectRepresentation, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable,
+    TypeVisitor,
 };
 use rustc_middle::ty::{Predicate, ToPredicate};
 use rustc_session::lint::builtin::WHERE_CLAUSES_OBJECT_SAFETY;
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index 8b15e10ba9c..a64179c14f5 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -38,6 +38,7 @@ use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::relate::TypeRelation;
 use rustc_middle::ty::subst::{Subst, SubstsRef};
+use rustc_middle::ty::TraitObjectRepresentation;
 use rustc_middle::ty::{self, EarlyBinder, PolyProjectionPredicate, ToPolyTraitRef, ToPredicate};
 use rustc_middle::ty::{Ty, TyCtxt, TypeFoldable, TypeVisitable};
 use rustc_span::symbol::sym;
@@ -1865,6 +1866,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             | ty::Array(..)
             | ty::Closure(..)
             | ty::Never
+            | ty::Dynamic(_, _, TraitObjectRepresentation::Sized)
             | ty::Error(_) => {
                 // safe for everything
                 Where(ty::Binder::dummy(Vec::new()))