)
}
- /// Transform a `PolyTraitRef` into a `PolyExistentialTraitRef` by
- /// removing the dummy `Self` type (`trait_object_dummy_self`).
- fn trait_ref_to_existential(&self, trait_ref: ty::TraitRef<'tcx>)
- -> ty::ExistentialTraitRef<'tcx> {
- if trait_ref.self_ty() != self.tcx().types.trait_object_dummy_self {
- bug!("trait_ref_to_existential called on {:?} with non-dummy Self", trait_ref);
- }
- ty::ExistentialTraitRef::erase_self_ty(self.tcx(), trait_ref)
- }
-
fn conv_object_ty_poly_trait_ref(&self,
span: Span,
trait_bounds: &[hir::PolyTraitRef],
debug!("regular_traits: {:?}", regular_traits);
debug!("auto_traits: {:?}", auto_traits);
+ // Transform a `PolyTraitRef` into a `PolyExistentialTraitRef` by
+ // removing the dummy `Self` type (`trait_object_dummy_self`).
+ let trait_ref_to_existential = |trait_ref: ty::TraitRef<'tcx>| {
+ if trait_ref.self_ty() != dummy_self {
+ // FIXME: There appears to be a missing filter on top of `expand_trait_aliases`,
+ // which picks up non-supertraits where clauses - but also, the object safety
+ // completely ignores trait aliases, which could be object safety hazards. We
+ // `delay_span_bug` here to avoid an ICE in stable even when the feature is
+ // disabled. (#66420)
+ tcx.sess.delay_span_bug(DUMMY_SP, &format!(
+ "trait_ref_to_existential called on {:?} with non-dummy Self",
+ trait_ref,
+ ));
+ }
+ ty::ExistentialTraitRef::erase_self_ty(tcx, trait_ref)
+ };
+
// Erase the `dummy_self` (`trait_object_dummy_self`) used above.
let existential_trait_refs = regular_traits.iter().map(|i| {
- i.trait_ref().map_bound(|trait_ref| self.trait_ref_to_existential(trait_ref))
+ i.trait_ref().map_bound(|trait_ref| trait_ref_to_existential(trait_ref))
});
let existential_projections = bounds.projection_bounds.iter().map(|(bound, _)| {
bound.map_bound(|b| {
- let trait_ref = self.trait_ref_to_existential(b.projection_ty.trait_ref(tcx));
+ let trait_ref = trait_ref_to_existential(b.projection_ty.trait_ref(tcx));
ty::ExistentialProjection {
ty: b.ty,
item_def_id: b.projection_ty.item_def_id,