Rollup merge of #107780 - compiler-errors:instantiate-binder, r=lcnr

[rust.git] / compiler / rustc_trait_selection / src / traits / project.rs

diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 81966f3fcb231791b5cc098dab611e9b81fde698..aa81bc640aa6c56367e4e9cdf87abf9e7e73984e 100644 (file)
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -148,7 +148,7 @@ fn push_candidate(&mut self, candidate: ProjectionCandidate<'tcx>) -> bool {
                 }
 
                 // Prefer where-clauses. As in select, if there are multiple
-                // candidates, we prefer where-clause candidates over impls.  This
+                // candidates, we prefer where-clause candidates over impls. This
                 // may seem a bit surprising, since impls are the source of
                 // "truth" in some sense, but in fact some of the impls that SEEM
                 // applicable are not, because of nested obligations. Where
@@ -215,7 +215,7 @@ pub(super) fn poly_project_and_unify_type<'cx, 'tcx>(
     let r = infcx.commit_if_ok(|_snapshot| {
         let old_universe = infcx.universe();
         let placeholder_predicate =
-            infcx.replace_bound_vars_with_placeholders(obligation.predicate);
+            infcx.instantiate_binder_with_placeholders(obligation.predicate);
         let new_universe = infcx.universe();
 
         let placeholder_obligation = obligation.with(infcx.tcx, placeholder_predicate);
@@ -783,7 +783,7 @@ fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
             }
             ty::Bound(debruijn, bound_ty) if debruijn >= self.current_index => {
                 let universe = self.universe_for(debruijn);
-                let p = ty::PlaceholderType { universe, name: bound_ty.var };
+                let p = ty::PlaceholderType { universe, name: bound_ty.kind };
                 self.mapped_types.insert(p, bound_ty);
                 self.infcx.tcx.mk_ty(ty::Placeholder(p))
             }
@@ -1034,7 +1034,7 @@ fn opt_normalize_projection_type<'a, 'b, 'tcx>(
         }
         Err(ProjectionCacheEntry::InProgress) => {
             // Under lazy normalization, this can arise when
-            // bootstrapping.  That is, imagine an environment with a
+            // bootstrapping. That is, imagine an environment with a
             // where-clause like `A::B == u32`. Now, if we are asked
             // to normalize `A::B`, we will want to check the
             // where-clauses in scope. So we will try to unify `A::B`
@@ -1375,7 +1375,7 @@ fn assemble_candidates_from_trait_def<'cx, 'tcx>(
     // Check whether the self-type is itself a projection.
     // If so, extract what we know from the trait and try to come up with a good answer.
     let bounds = match *obligation.predicate.self_ty().kind() {
-        ty::Alias(_, ref data) => tcx.bound_item_bounds(data.def_id).subst(tcx, data.substs),
+        ty::Alias(_, ref data) => tcx.item_bounds(data.def_id).subst(tcx, data.substs),
         ty::Infer(ty::TyVar(_)) => {
             // If the self-type is an inference variable, then it MAY wind up
             // being a projected type, so induce an ambiguity.
@@ -1605,6 +1605,7 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         | ty::Closure(..)
                         | ty::Generator(..)
                         | ty::GeneratorWitness(..)
+                        | ty::GeneratorWitnessMIR(..)
                         | ty::Never
                         | ty::Tuple(..)
                         // Integers and floats always have `u8` as their discriminant.
@@ -1654,6 +1655,7 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         | ty::Closure(..)
                         | ty::Generator(..)
                         | ty::GeneratorWitness(..)
+                        | ty::GeneratorWitnessMIR(..)
                         | ty::Never
                         // Extern types have unit metadata, according to RFC 2850
                         | ty::Foreign(_)
@@ -2044,7 +2046,7 @@ fn confirm_param_env_candidate<'cx, 'tcx>(
     let cause = &obligation.cause;
     let param_env = obligation.param_env;
 
-    let cache_entry = infcx.replace_bound_vars_with_fresh_vars(
+    let cache_entry = infcx.instantiate_binder_with_fresh_vars(
         cause.span,
         LateBoundRegionConversionTime::HigherRankedType,
         poly_cache_entry,
@@ -2259,25 +2261,23 @@ fn confirm_impl_trait_in_trait_candidate<'tcx>(
         tcx.predicates_of(impl_fn_def_id).instantiate(tcx, impl_fn_substs),
         &mut obligations,
     );
-    obligations.extend(std::iter::zip(predicates.predicates, predicates.spans).map(
-        |(pred, span)| {
-            Obligation::with_depth(
-                tcx,
-                ObligationCause::new(
-                    obligation.cause.span,
-                    obligation.cause.body_id,
-                    if span.is_dummy() {
-                        super::ItemObligation(impl_fn_def_id)
-                    } else {
-                        super::BindingObligation(impl_fn_def_id, span)
-                    },
-                ),
-                obligation.recursion_depth + 1,
-                obligation.param_env,
-                pred,
-            )
-        },
-    ));
+    obligations.extend(predicates.into_iter().map(|(pred, span)| {
+        Obligation::with_depth(
+            tcx,
+            ObligationCause::new(
+                obligation.cause.span,
+                obligation.cause.body_id,
+                if span.is_dummy() {
+                    super::ItemObligation(impl_fn_def_id)
+                } else {
+                    super::BindingObligation(impl_fn_def_id, span)
+                },
+            ),
+            obligation.recursion_depth + 1,
+            obligation.param_env,
+            pred,
+        )
+    }));
 
     let ty = normalize_with_depth_to(
         selcx,
@@ -2303,10 +2303,10 @@ fn assoc_ty_own_obligations<'cx, 'tcx>(
     nested: &mut Vec<PredicateObligation<'tcx>>,
 ) {
     let tcx = selcx.tcx();
-    let own = tcx
+    let predicates = tcx
         .predicates_of(obligation.predicate.def_id)
         .instantiate_own(tcx, obligation.predicate.substs);
-    for (predicate, span) in std::iter::zip(own.predicates, own.spans) {
+    for (predicate, span) in predicates {
         let normalized = normalize_with_depth_to(
             selcx,
             obligation.param_env,