Rollup of 6 pull requests

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -1970,7 +1970,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             ) = &qself.kind {
                                 // If the path segment already has type params, we want to overwrite
                                 // them.
-                                match &path.segments[..] {
+                                match &path.segments {
                                     // `segment` is the previous to last element on the path,
                                     // which would normally be the `enum` itself, while the last
                                     // `_` `PathSegment` corresponds to the variant.
@@ -2670,7 +2670,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 // `Self` in trait or type alias.
                 assert_eq!(opt_self_ty, None);
                 self.prohibit_generics(path.segments.iter(), |err| {
-                    if let [hir::PathSegment { args: Some(args), ident, .. }] = &path.segments[..] {
+                    if let [hir::PathSegment { args: Some(args), ident, .. }] = &path.segments {
                         err.span_suggestion_verbose(
                             ident.span.shrink_to_hi().to(args.span_ext),
                             "the `Self` type doesn't accept type parameters",

compiler/rustc_hir_typeck/src/demand.rs

@@ -298,6 +298,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // call's arguments and we can provide a more explicit span.
                 let sig = self.tcx.fn_sig(def_id).subst_identity();
                 let def_self_ty = sig.input(0).skip_binder();
+                let param_tys = sig.inputs().skip_binder().iter().skip(1);
+                // If there's an arity mismatch, pointing out the call as the source of an inference
+                // can be misleading, so we skip it.
+                if param_tys.len() != args.len() {
+                    continue;
+                }
                 let rcvr_ty = self.node_ty(rcvr.hir_id);
                 // Get the evaluated type *after* calling the method call, so that the influence
                 // of the arguments can be reflected in the receiver type. The receiver
@@ -323,13 +329,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let mut param_found = FxHashMap::default();
                 if self.can_eq(self.param_env, ty, found) {
                     // We only point at the first place where the found type was inferred.
-                    for (i, param_ty) in sig.inputs().skip_binder().iter().skip(1).enumerate() {
+                    for (param_ty, arg) in param_tys.zip(args) {
                         if def_self_ty.contains(*param_ty) && let ty::Param(_) = param_ty.kind() {
                             // We found an argument that references a type parameter in `Self`,
                             // so we assume that this is the argument that caused the found
                             // type, which we know already because of `can_eq` above was first
                             // inferred in this method call.
-                            let arg = &args[i];
                             let arg_ty = self.node_ty(arg.hir_id);
                             if !arg.span.overlaps(mismatch_span) {
                                 err.span_label(

compiler/rustc_hir_typeck/src/method/probe.rs

@@ -517,8 +517,7 @@ fn method_autoderef_steps<'tcx>(
         .by_ref()
         .map(|(ty, d)| {
             let step = CandidateStep {
-                self_ty: infcx
-                    .make_query_response_ignoring_pending_obligations(inference_vars.clone(), ty),
+                self_ty: infcx.make_query_response_ignoring_pending_obligations(inference_vars, ty),
                 autoderefs: d,
                 from_unsafe_deref: reached_raw_pointer,
                 unsize: false,

compiler/rustc_middle/src/ty/flags.rs

@@ -125,7 +125,7 @@ impl FlagComputation {
                 self.bound_computation(ts, |flags, ts| flags.add_tys(ts));
             }
 
-            &ty::GeneratorWitnessMIR(_, ref substs) => {
+            ty::GeneratorWitnessMIR(_, substs) => {
                 let should_remove_further_specializable =
                     !self.flags.contains(TypeFlags::STILL_FURTHER_SPECIALIZABLE);
                 self.add_substs(substs);

compiler/rustc_query_system/src/query/caches.rs

@@ -92,7 +92,7 @@ where
         let mut lock = self.cache.lock();
         // We may be overwriting another value. This is all right, since the dep-graph
         // will check that the fingerprint matches.
-        lock.insert(key, (value.clone(), index));
+        lock.insert(key, (value, index));
         value
     }
 
@@ -153,7 +153,7 @@ where
 
     #[inline]
     fn complete(&self, _key: (), value: V, index: DepNodeIndex) -> Self::Stored {
-        *self.cache.lock() = Some((value.clone(), index));
+        *self.cache.lock() = Some((value, index));
         value
     }
 
@@ -283,7 +283,7 @@ where
         let mut lock = self.cache.get_shard_by_hash(key.index() as u64).lock();
         #[cfg(not(parallel_compiler))]
         let mut lock = self.cache.lock();
-        lock.insert(key, (value.clone(), index));
+        lock.insert(key, (value, index));
         value
     }
 

compiler/rustc_trait_selection/src/solve/mod.rs

@@ -547,7 +547,7 @@ impl<'tcx> EvalCtxt<'_, 'tcx> {
             response.value.certainty == Certainty::Yes
                 && response.has_no_inference_or_external_constraints()
         }) {
-            return Ok(response.clone());
+            return Ok(*response);
         }
 
         let certainty = candidates.iter().fold(Certainty::AMBIGUOUS, |certainty, response| {

compiler/rustc_trait_selection/src/traits/object_safety.rs

@@ -599,7 +599,7 @@ fn virtual_call_violation_for_method<'tcx>(
             return false;
         }
 
-        contains_illegal_self_type_reference(tcx, trait_def_id, pred.clone())
+        contains_illegal_self_type_reference(tcx, trait_def_id, pred)
     }) {
         return Some(MethodViolationCode::WhereClauseReferencesSelf);
     }

compiler/rustc_type_ir/src/sty.rs

@@ -336,7 +336,7 @@ impl<I: Interner> PartialEq for TyKind<I> {
                 a_d == b_d && a_s == b_s && a_m == b_m
             }
             (GeneratorWitness(a_g), GeneratorWitness(b_g)) => a_g == b_g,
-            (&GeneratorWitnessMIR(ref a_d, ref a_s), &GeneratorWitnessMIR(ref b_d, ref b_s)) => {
+            (GeneratorWitnessMIR(a_d, a_s), GeneratorWitnessMIR(b_d, b_s)) => {
                 a_d == b_d && a_s == b_s
             }
             (Tuple(a_t), Tuple(b_t)) => a_t == b_t,
@@ -397,8 +397,8 @@ impl<I: Interner> Ord for TyKind<I> {
                 }
                 (GeneratorWitness(a_g), GeneratorWitness(b_g)) => a_g.cmp(b_g),
                 (
-                    &GeneratorWitnessMIR(ref a_d, ref a_s),
-                    &GeneratorWitnessMIR(ref b_d, ref b_s),
+                    GeneratorWitnessMIR(a_d, a_s),
+                    GeneratorWitnessMIR(b_d, b_s),
                 ) => match Ord::cmp(a_d, b_d) {
                     Ordering::Equal => Ord::cmp(a_s, b_s),
                     cmp => cmp,

library/core/src/cmp.rs

@@ -1491,9 +1491,10 @@ mod impls {
         }
     }
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<A: ?Sized, B: ?Sized> PartialOrd<&B> for &A
+    #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+    impl<A: ?Sized, B: ?Sized> const PartialOrd<&B> for &A
     where
-        A: PartialOrd<B>,
+        A: ~const PartialOrd<B>,
     {
         #[inline]
         fn partial_cmp(&self, other: &&B) -> Option<Ordering> {