Rollup merge of #106699 - eholk:await-chains-drop-tracking, r=wesleywiser

[rust.git] / compiler / rustc_hir_analysis / src / check / compare_impl_item.rs

diff --git a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
index 2cdf75794713fe67666bc377a607976422e188ba..06b69599b585e0fab1fe81e865bd31dbd1607185 100644 (file)
--- a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
+++ b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
@@ -138,7 +138,7 @@ pub(super) fn compare_impl_method<'tcx>(
 ///     <'a> fn(t: &'i0 U0, m: &'a) -> Foo
 ///
 /// This type is also the same but the name of the bound region (`'a`
-/// vs `'b`).  However, the normal subtyping rules on fn types handle
+/// vs `'b`). However, the normal subtyping rules on fn types handle
 /// this kind of equivalency just fine.
 ///
 /// We now use these substitutions to ensure that all declared bounds are
@@ -209,9 +209,11 @@ fn compare_method_predicate_entailment<'tcx>(
     //
     // We then register the obligations from the impl_m and check to see
     // if all constraints hold.
-    hybrid_preds
-        .predicates
-        .extend(trait_m_predicates.instantiate_own(tcx, trait_to_placeholder_substs).predicates);
+    hybrid_preds.predicates.extend(
+        trait_m_predicates
+            .instantiate_own(tcx, trait_to_placeholder_substs)
+            .map(|(predicate, _)| predicate),
+    );
 
     // Construct trait parameter environment and then shift it into the placeholder viewpoint.
     // The key step here is to update the caller_bounds's predicates to be
@@ -230,7 +232,7 @@ fn compare_method_predicate_entailment<'tcx>(
     debug!("compare_impl_method: caller_bounds={:?}", param_env.caller_bounds());
 
     let impl_m_own_bounds = impl_m_predicates.instantiate_own(tcx, impl_to_placeholder_substs);
-    for (predicate, span) in iter::zip(impl_m_own_bounds.predicates, impl_m_own_bounds.spans) {
+    for (predicate, span) in impl_m_own_bounds {
         let normalize_cause = traits::ObligationCause::misc(span, impl_m_hir_id);
         let predicate = ocx.normalize(&normalize_cause, param_env, predicate);
 
@@ -616,7 +618,8 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>(
 ) -> Result<&'tcx FxHashMap<DefId, Ty<'tcx>>, ErrorGuaranteed> {
     let impl_m = tcx.opt_associated_item(def_id).unwrap();
     let trait_m = tcx.opt_associated_item(impl_m.trait_item_def_id.unwrap()).unwrap();
-    let impl_trait_ref = tcx.impl_trait_ref(impl_m.impl_container(tcx).unwrap()).unwrap();
+    let impl_trait_ref =
+        tcx.impl_trait_ref(impl_m.impl_container(tcx).unwrap()).unwrap().subst_identity();
     let param_env = tcx.param_env(def_id);
 
     // First, check a few of the same things as `compare_impl_method`,
@@ -761,7 +764,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>(
         match infcx.fully_resolve(ty) {
             Ok(ty) => {
                 // `ty` contains free regions that we created earlier while liberating the
-                // trait fn signature.  However, projection normalization expects `ty` to
+                // trait fn signature. However, projection normalization expects `ty` to
                 // contains `def_id`'s early-bound regions.
                 let id_substs = InternalSubsts::identity_for_item(tcx, def_id);
                 debug!(?id_substs, ?substs);
@@ -1019,7 +1022,7 @@ fn check_region_bounds_on_impl_item<'tcx>(
 
     // Must have same number of early-bound lifetime parameters.
     // Unfortunately, if the user screws up the bounds, then this
-    // will change classification between early and late.  E.g.,
+    // will change classification between early and late. E.g.,
     // if in trait we have `<'a,'b:'a>`, and in impl we just have
     // `<'a,'b>`, then we have 2 early-bound lifetime parameters
     // in trait but 0 in the impl. But if we report "expected 2
@@ -1130,9 +1133,9 @@ fn compare_self_type<'tcx>(
     impl_trait_ref: ty::TraitRef<'tcx>,
 ) -> Result<(), ErrorGuaranteed> {
     // Try to give more informative error messages about self typing
-    // mismatches.  Note that any mismatch will also be detected
+    // mismatches. Note that any mismatch will also be detected
     // below, where we construct a canonical function type that
-    // includes the self parameter as a normal parameter.  It's just
+    // includes the self parameter as a normal parameter. It's just
     // that the error messages you get out of this code are a bit more
     // inscrutable, particularly for cases where one method has no
     // self.
@@ -1684,7 +1687,8 @@ pub(super) fn compare_impl_const_raw(
 ) -> Result<(), ErrorGuaranteed> {
     let impl_const_item = tcx.associated_item(impl_const_item_def);
     let trait_const_item = tcx.associated_item(trait_const_item_def);
-    let impl_trait_ref = tcx.impl_trait_ref(impl_const_item.container_id(tcx)).unwrap();
+    let impl_trait_ref =
+        tcx.impl_trait_ref(impl_const_item.container_id(tcx)).unwrap().subst_identity();
     debug!("compare_const_impl(impl_trait_ref={:?})", impl_trait_ref);
 
     let impl_c_span = tcx.def_span(impl_const_item_def.to_def_id());
@@ -1826,8 +1830,7 @@ fn compare_type_predicate_entailment<'tcx>(
     check_region_bounds_on_impl_item(tcx, impl_ty, trait_ty, false)?;
 
     let impl_ty_own_bounds = impl_ty_predicates.instantiate_own(tcx, impl_substs);
-
-    if impl_ty_own_bounds.is_empty() {
+    if impl_ty_own_bounds.len() == 0 {
         // Nothing to check.
         return Ok(());
     }
@@ -1842,9 +1845,11 @@ fn compare_type_predicate_entailment<'tcx>(
     // associated type in the trait are assumed.
     let impl_predicates = tcx.predicates_of(impl_ty_predicates.parent.unwrap());
     let mut hybrid_preds = impl_predicates.instantiate_identity(tcx);
-    hybrid_preds
-        .predicates
-        .extend(trait_ty_predicates.instantiate_own(tcx, trait_to_impl_substs).predicates);
+    hybrid_preds.predicates.extend(
+        trait_ty_predicates
+            .instantiate_own(tcx, trait_to_impl_substs)
+            .map(|(predicate, _)| predicate),
+    );
 
     debug!("compare_type_predicate_entailment: bounds={:?}", hybrid_preds);
 
@@ -1860,9 +1865,7 @@ fn compare_type_predicate_entailment<'tcx>(
 
     debug!("compare_type_predicate_entailment: caller_bounds={:?}", param_env.caller_bounds());
 
-    assert_eq!(impl_ty_own_bounds.predicates.len(), impl_ty_own_bounds.spans.len());
-    for (span, predicate) in std::iter::zip(impl_ty_own_bounds.spans, impl_ty_own_bounds.predicates)
-    {
+    for (predicate, span) in impl_ty_own_bounds {
         let cause = ObligationCause::misc(span, impl_ty_hir_id);
         let predicate = ocx.normalize(&cause, param_env, predicate);