Rollup of 6 pull requests

CONTRIBUTING.md

@@ -31,8 +31,8 @@ bootstrapping, the compiler architecture, source code representation, and more.
 
 ## [Getting help](https://rustc-dev-guide.rust-lang.org/getting-started.html#asking-questions)
 
-There are many ways you can get help when you're stuck. Rust has many platforms for this:
-[internals], [rust-zulip], and [rust-discord]. It is recommended to ask for help on
+There are many ways you can get help when you're stuck. Rust has two platforms for this:
+[internals] and [rust-zulip]. It is recommended to ask for help on
 the [rust-zulip], but any of these platforms are great ways to seek help and even
 find a mentor! You can learn more about asking questions and getting help in the
 [Asking Questions](https://rustc-dev-guide.rust-lang.org/getting-started.html#asking-questions) chapter of the [rustc-dev-guide].

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -702,7 +702,7 @@ pub fn compile_declarative_macro(
             kinds |= MacroKinds::DERIVE;
             let derive_keyword_span = p.prev_token.span;
             if !features.macro_derive() {
-                feature_err(sess, sym::macro_attr, span, "`macro_rules!` derives are unstable")
+                feature_err(sess, sym::macro_derive, span, "`macro_rules!` derives are unstable")
                     .emit();
             }
             if let Some(guar) = check_no_eof(sess, &p, "expected `()` after `derive`") {

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -2194,7 +2194,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     fn suggest_associated_call_syntax(
         &self,
         err: &mut Diag<'_>,
-        static_candidates: &Vec<CandidateSource>,
+        static_candidates: &[CandidateSource],
         rcvr_ty: Ty<'tcx>,
         source: SelfSource<'tcx>,
         item_name: Ident,
@@ -2422,7 +2422,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
                     let span_included = match parent_expr.kind {
                         hir::ExprKind::Struct(_, eps, _) => {
-                            eps.len() > 0 && eps.last().is_some_and(|ep| ep.span.contains(span))
+                            eps.last().is_some_and(|ep| ep.span.contains(span))
                         }
                         // `..=` desugars into `::std::ops::RangeInclusive::new(...)`.
                         hir::ExprKind::Call(func, ..) => func.span.contains(span),
@@ -2484,7 +2484,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             simplify_type(tcx, ty, TreatParams::InstantiateWithInfer)
                 .and_then(|simp| {
                     tcx.incoherent_impls(simp)
-                        .into_iter()
+                        .iter()
                         .find_map(|&id| self.associated_value(id, item_name))
                 })
                 .is_some()
@@ -2617,7 +2617,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
                 if let Node::Expr(call_expr) = self.tcx.parent_hir_node(seg1.hir_id)
                     && let ControlFlow::Break(Some(expr)) =
-                        (LetVisitor { ident_name: seg1.ident.name }).visit_body(&body)
+                        (LetVisitor { ident_name: seg1.ident.name }).visit_body(body)
                     && let Some(self_ty) = self.node_ty_opt(expr.hir_id)
                 {
                     let probe = self.lookup_probe_for_diagnostic(
@@ -2960,14 +2960,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             .collect::<Vec<_>>()
             .into();
         for pred in &local_preds {
-            match pred.self_ty().kind() {
-                ty::Adt(def, _) => {
-                    local_spans.push_span_label(
-                        self.tcx.def_span(def.did()),
-                        format!("must implement `{}`", pred.trait_ref.print_trait_sugared()),
-                    );
-                }
-                _ => {}
+            if let ty::Adt(def, _) = pred.self_ty().kind() {
+                local_spans.push_span_label(
+                    self.tcx.def_span(def.did()),
+                    format!("must implement `{}`", pred.trait_ref.print_trait_sugared()),
+                );
             }
         }
         if local_spans.primary_span().is_some() {
@@ -3006,14 +3003,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             .collect::<Vec<_>>()
             .into();
         for pred in &foreign_preds {
-            match pred.self_ty().kind() {
-                ty::Adt(def, _) => {
-                    foreign_spans.push_span_label(
-                        self.tcx.def_span(def.did()),
-                        format!("not implement `{}`", pred.trait_ref.print_trait_sugared()),
-                    );
-                }
-                _ => {}
+            if let ty::Adt(def, _) = pred.self_ty().kind() {
+                foreign_spans.push_span_label(
+                    self.tcx.def_span(def.did()),
+                    format!("not implement `{}`", pred.trait_ref.print_trait_sugared()),
+                );
             }
         }
         if foreign_spans.primary_span().is_some() {
@@ -3595,7 +3589,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // would take care of them.
                     && !skippable.contains(&Some(pick.item.container_id(self.tcx)))
                     // Do not suggest pinning when the method is directly on `Pin`.
-                    && pick.item.impl_container(self.tcx).map_or(true, |did| {
+                    && pick.item.impl_container(self.tcx).is_none_or(|did| {
                         match self.tcx.type_of(did).skip_binder().kind() {
                             ty::Adt(def, _) => Some(def.did()) != self.tcx.lang_items().pin_type(),
                             _ => true,
@@ -3653,7 +3647,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 vec![
                                     (
                                         rcvr.span.shrink_to_lo(),
-                                        format!("let mut pinned = std::pin::pin!("),
+                                        "let mut pinned = std::pin::pin!(".to_string(),
                                     ),
                                     (
                                         rcvr.span.shrink_to_hi(),
@@ -4128,7 +4122,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         );
         let trait_span = self.tcx.def_span(trait_def_id);
         let mut multi_span: MultiSpan = trait_span.into();
-        multi_span.push_span_label(trait_span, format!("this is the trait that is needed"));
+        multi_span.push_span_label(trait_span, "this is the trait that is needed".to_string());
         let descr = self.tcx.associated_item(item_def_id).descr();
         let rcvr_ty =
             rcvr_ty.map(|t| format!("`{t}`")).unwrap_or_else(|| "the receiver".to_string());
@@ -4146,7 +4140,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }
             multi_span.push_span_label(
                 self.tcx.def_span(def_id),
-                format!("this is the trait that was imported"),
+                "this is the trait that was imported".to_string(),
             );
         }
         err.span_note(multi_span, msg);

compiler/rustc_hir_typeck/src/op.rs

@@ -566,7 +566,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     rhs_ty,
                     lhs_expr,
                     lhs_ty,
-                    |lhs_ty, rhs_ty| is_compatible_after_call(lhs_ty, rhs_ty),
+                    is_compatible_after_call,
                 ) {
                     // Cool
                 }
@@ -1170,8 +1170,8 @@ fn deref_ty_if_possible(ty: Ty<'_>) -> Ty<'_> {
     }
 }
 
-/// Returns `true` if this is a built-in arithmetic operation (e.g., u32
-/// + u32, i16x4 == i16x4) and false if these types would have to be
+/// Returns `true` if this is a built-in arithmetic operation (e.g.,
+/// u32 + u32, i16x4 == i16x4) and false if these types would have to be
 /// overloaded to be legal. There are two reasons that we distinguish
 /// builtin operations from overloaded ones (vs trying to drive
 /// everything uniformly through the trait system and intrinsics or
@@ -1191,7 +1191,7 @@ fn is_builtin_binop<'tcx>(lhs: Ty<'tcx>, rhs: Ty<'tcx>, category: BinOpCategory)
     // (See https://github.com/rust-lang/rust/issues/57447.)
     let (lhs, rhs) = (deref_ty_if_possible(lhs), deref_ty_if_possible(rhs));
 
-    match category.into() {
+    match category {
         BinOpCategory::Shortcircuit => true,
         BinOpCategory::Shift => {
             lhs.references_error()

library/alloc/src/collections/btree/node.rs

@@ -67,6 +67,10 @@ struct LeafNode<K, V> {
 
 impl<K, V> LeafNode<K, V> {
     /// Initializes a new `LeafNode` in-place.
+    ///
+    /// # Safety
+    ///
+    /// The caller must ensure that `this` points to a (possibly uninitialized) `LeafNode`
     unsafe fn init(this: *mut Self) {
         // As a general policy, we leave fields uninitialized if they can be, as this should
         // be both slightly faster and easier to track in Valgrind.
@@ -79,9 +83,11 @@ impl<K, V> LeafNode<K, V> {
 
     /// Creates a new boxed `LeafNode`.
     fn new<A: Allocator + Clone>(alloc: A) -> Box<Self, A> {
+        let mut leaf = Box::new_uninit_in(alloc);
         unsafe {
-            let mut leaf = Box::new_uninit_in(alloc);
+            // SAFETY: `leaf` points to a `LeafNode`
             LeafNode::init(leaf.as_mut_ptr());
+            // SAFETY: `leaf` was just initialized
             leaf.assume_init()
         }
     }

library/core/src/cmp.rs

@@ -1351,7 +1351,9 @@ pub macro Ord($item:item) {
 #[rustc_diagnostic_item = "PartialOrd"]
 #[allow(multiple_supertrait_upcastable)] // FIXME(sized_hierarchy): remove this
 #[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
-pub const trait PartialOrd<Rhs: PointeeSized = Self>: PartialEq<Rhs> + PointeeSized {
+pub const trait PartialOrd<Rhs: PointeeSized = Self>:
+    [const] PartialEq<Rhs> + PointeeSized
+{
     /// This method returns an ordering between `self` and `other` values if one exists.
     ///
     /// # Examples

tests/ui/feature-gates/feature-gate-macro-derive.stderr

@@ -4,8 +4,8 @@ error[E0658]: `macro_rules!` derives are unstable
 LL | macro_rules! MyDerive { derive() {} => {} }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #83527 <https://github.com/rust-lang/rust/issues/83527> for more information
-   = help: add `#![feature(macro_attr)]` to the crate attributes to enable
+   = note: see issue #143549 <https://github.com/rust-lang/rust/issues/143549> for more information
+   = help: add `#![feature(macro_derive)]` to the crate attributes to enable
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error: aborting due to 1 previous error

x

@@ -15,7 +15,8 @@ realpath() {
     if [ -L "$path" ]; then
         readlink -f "$path"
     elif [ -d "$path" ]; then
-        (cd -P "$path" && pwd)
+        # "cd" is not always silent (e.g. when CDPATH is set), so discard its output.
+        (cd -P "$path" >/dev/null && pwd)
     else
         echo "$(realpath "$(dirname "$path")")/$(basename "$path")"
     fi