Merging upstream version 1.76.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 19 insertions, 4 deletions

diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs
index 1487f40fd..f1c9bb23e 100644
--- a/compiler/rustc_ty_utils/src/instance.rs
+++ b/compiler/rustc_ty_utils/src/instance.rs
@@ -61,7 +61,7 @@ fn resolve_instance<'tcx>(
 
         Ok(Some(Instance { def, args }))
     };
-    debug!("inner_resolve_instance: result={:?}", result);
+    debug!("resolve_instance: result={:?}", result);
     result
 }
 
@@ -79,7 +79,7 @@ fn resolve_associated_item<'tcx>(
     let vtbl = match tcx.codegen_select_candidate((param_env, trait_ref)) {
         Ok(vtbl) => vtbl,
         Err(CodegenObligationError::Ambiguity) => {
-            let reported = tcx.sess.delay_span_bug(
+            let reported = tcx.sess.span_delayed_bug(
                 tcx.def_span(trait_item_id),
                 format!(
                     "encountered ambiguity selecting `{trait_ref:?}` during codegen, presuming due to \
@@ -171,7 +171,7 @@ fn resolve_associated_item<'tcx>(
 
             // Any final impl is required to define all associated items.
             if !leaf_def.item.defaultness(tcx).has_value() {
-                let guard = tcx.sess.delay_span_bug(
+                let guard = tcx.sess.span_delayed_bug(
                     tcx.def_span(leaf_def.item.def_id),
                     "missing value for assoc item in impl",
                 );
@@ -271,6 +271,21 @@ fn resolve_associated_item<'tcx>(
                     debug_assert!(tcx.defaultness(trait_item_id).has_value());
                     Some(Instance::new(trait_item_id, rcvr_args))
                 }
+            } else if Some(trait_ref.def_id) == lang_items.async_iterator_trait() {
+                let ty::Coroutine(coroutine_def_id, args, _) = *rcvr_args.type_at(0).kind() else {
+                    bug!()
+                };
+
+                if cfg!(debug_assertions) && tcx.item_name(trait_item_id) != sym::poll_next {
+                    span_bug!(
+                        tcx.def_span(coroutine_def_id),
+                        "no definition for `{trait_ref}::{}` for built-in coroutine type",
+                        tcx.item_name(trait_item_id)
+                    )
+                }
+
+                // `AsyncIterator::poll_next` is generated by the compiler.
+                Some(Instance { def: ty::InstanceDef::Item(coroutine_def_id), args })
             } else if Some(trait_ref.def_id) == lang_items.coroutine_trait() {
                 let ty::Coroutine(coroutine_def_id, args, _) = *rcvr_args.type_at(0).kind() else {
                     bug!()
@@ -328,6 +343,6 @@ fn resolve_associated_item<'tcx>(
     })
 }
 
-pub fn provide(providers: &mut Providers) {
+pub(crate) fn provide(providers: &mut Providers) {
     *providers = Providers { resolve_instance, ..*providers };
 }