From 91fd862df011168e7634f79fc2f2c9fb15a7afd3 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Tue, 3 Jan 2023 02:49:31 +0000
Subject: instantiate_own doesn't need to return a pair of vectors

---
 compiler/rustc_trait_selection/src/traits/project.rs             | 4 ++--
 compiler/rustc_trait_selection/src/traits/select/confirmation.rs | 5 ++---
 compiler/rustc_trait_selection/src/traits/vtable.rs              | 5 ++++-
 3 files changed, 8 insertions(+), 6 deletions(-)

(limited to 'compiler/rustc_trait_selection/src')

diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 81966f3fcb2..15320916fbe 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -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,
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index a41d10f1043..d4ac461690c 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -185,9 +185,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         })?);
 
         if let ty::Alias(ty::Projection, ..) = placeholder_self_ty.kind() {
-            let predicates = tcx.predicates_of(def_id).instantiate_own(tcx, substs).predicates;
-            debug!(?predicates, "projection predicates");
-            for predicate in predicates {
+            let predicates = tcx.predicates_of(def_id).instantiate_own(tcx, substs);
+            for (predicate, _) in predicates {
                 let normalized = normalize_with_depth_to(
                     self,
                     obligation.param_env,
diff --git a/compiler/rustc_trait_selection/src/traits/vtable.rs b/compiler/rustc_trait_selection/src/traits/vtable.rs
index 5ec9c2a24cd..64daca714c3 100644
--- a/compiler/rustc_trait_selection/src/traits/vtable.rs
+++ b/compiler/rustc_trait_selection/src/traits/vtable.rs
@@ -261,7 +261,10 @@ fn vtable_entries<'tcx>(
                     // Note that this method could then never be called, so we
                     // do not want to try and codegen it, in that case (see #23435).
                     let predicates = tcx.predicates_of(def_id).instantiate_own(tcx, substs);
-                    if impossible_predicates(tcx, predicates.predicates) {
+                    if impossible_predicates(
+                        tcx,
+                        predicates.map(|(predicate, _)| predicate).collect(),
+                    ) {
                         debug!("vtable_entries: predicates do not hold");
                         return VtblEntry::Vacant;
                     }
-- 
cgit 1.4.1-3-g733a5