Auto merge of rust-lang#102471 - Dylan-DPC:rollup-ij3okjt, r=Dylan-DPC

Rollup of 7 pull requests

Successful merges:

 - rust-lang#102336 (Fix associated type bindings with anon const in GAT position)
 - rust-lang#102342 (Add negation methods for signed non-zero integers.)
 - rust-lang#102385 (Don't export `__heap_base` and `__data_end` on wasm32-wasi.)
 - rust-lang#102435 (Improve example of Iterator::reduce)
 - rust-lang#102436 (rustdoc: clean up "normalize.css 8" input override CSS)
 - rust-lang#102452 (fix minor ungrammatical sentence)
 - rust-lang#102455 (Use let-chaining in `WhileTrue::check_expr`.)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -1320,10 +1320,12 @@ impl<'a> Linker for WasmLd<'a> {
 
         // LLD will hide these otherwise-internal symbols since it only exports
         // symbols explicitly passed via the `--export` flags above and hides all
-        // others. Various bits and pieces of tooling use this, so be sure these
-        // symbols make their way out of the linker as well.
-        self.cmd.arg("--export=__heap_base");
-        self.cmd.arg("--export=__data_end");
+        // others. Various bits and pieces of wasm32-unknown-unknown tooling use
+        // this, so be sure these symbols make their way out of the linker as well.
+        if self.sess.target.os == "unknown" {
+            self.cmd.arg("--export=__heap_base");
+            self.cmd.arg("--export=__data_end");
+        }
     }
 
     fn subsystem(&mut self, _subsystem: &str) {}

compiler/rustc_hir_analysis/src/collect/type_of.rs

@@ -333,7 +333,12 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                     find_opaque_ty_constraints_for_tait(tcx, def_id)
                 }
                 // Opaque types desugared from `impl Trait`.
-                ItemKind::OpaqueTy(OpaqueTy { origin: hir::OpaqueTyOrigin::FnReturn(owner) | hir::OpaqueTyOrigin::AsyncFn(owner), in_trait, .. }) => {
+                ItemKind::OpaqueTy(OpaqueTy {
+                    origin:
+                        hir::OpaqueTyOrigin::FnReturn(owner) | hir::OpaqueTyOrigin::AsyncFn(owner),
+                    in_trait,
+                    ..
+                }) => {
                     if in_trait {
                         span_bug!(item.span, "impl-trait in trait has no default")
                     } else {
@@ -378,7 +383,9 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
 
         Node::Field(field) => icx.to_ty(field.ty),
 
-        Node::Expr(&Expr { kind: ExprKind::Closure{..}, .. }) => tcx.typeck(def_id).node_type(hir_id),
+        Node::Expr(&Expr { kind: ExprKind::Closure { .. }, .. }) => {
+            tcx.typeck(def_id).node_type(hir_id)
+        }
 
         Node::AnonConst(_) if let Some(param) = tcx.opt_const_param_of(def_id) => {
             // We defer to `type_of` of the corresponding parameter
@@ -410,40 +417,91 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                 | Node::Item(&Item { kind: ItemKind::GlobalAsm(asm), .. })
                     if asm.operands.iter().any(|(op, _op_sp)| match op {
                         hir::InlineAsmOperand::Const { anon_const }
-                        | hir::InlineAsmOperand::SymFn { anon_const } => anon_const.hir_id == hir_id,
+                        | hir::InlineAsmOperand::SymFn { anon_const } => {
+                            anon_const.hir_id == hir_id
+                        }
                         _ => false,
                     }) =>
                 {
                     tcx.typeck(def_id).node_type(hir_id)
                 }
 
-                Node::Variant(Variant { disr_expr: Some(ref e), .. }) if e.hir_id == hir_id => tcx
-                    .adt_def(tcx.hir().get_parent_item(hir_id))
-                    .repr()
-                    .discr_type()
-                    .to_ty(tcx),
+                Node::Variant(Variant { disr_expr: Some(ref e), .. }) if e.hir_id == hir_id => {
+                    tcx.adt_def(tcx.hir().get_parent_item(hir_id)).repr().discr_type().to_ty(tcx)
+                }
 
-                Node::TypeBinding(binding @ &TypeBinding { hir_id: binding_id, ..  })
-                    if let Node::TraitRef(trait_ref) = tcx.hir().get(
-                        tcx.hir().get_parent_node(binding_id)
-                    ) =>
+                Node::TypeBinding(
+                    binding @ &TypeBinding {
+                        hir_id: binding_id,
+                        kind: TypeBindingKind::Equality { term: Term::Const(ref e) },
+                        ..
+                    },
+                ) if let Node::TraitRef(trait_ref) =
+                    tcx.hir().get(tcx.hir().get_parent_node(binding_id))
+                    && e.hir_id == hir_id =>
                 {
-                  let Some(trait_def_id) = trait_ref.trait_def_id() else {
-                    return tcx.ty_error_with_message(DUMMY_SP, "Could not find trait");
-                  };
-                  let assoc_items = tcx.associated_items(trait_def_id);
-                  let assoc_item = assoc_items.find_by_name_and_kind(
-                    tcx, binding.ident, ty::AssocKind::Const, def_id.to_def_id(),
-                  );
-                  if let Some(assoc_item) = assoc_item {
-                    tcx.type_of(assoc_item.def_id)
-                  } else {
-                      // FIXME(associated_const_equality): add a useful error message here.
-                      tcx.ty_error_with_message(
-                        DUMMY_SP,
-                        "Could not find associated const on trait",
-                    )
-                  }
+                    let Some(trait_def_id) = trait_ref.trait_def_id() else {
+                        return tcx.ty_error_with_message(DUMMY_SP, "Could not find trait");
+                    };
+                    let assoc_items = tcx.associated_items(trait_def_id);
+                    let assoc_item = assoc_items.find_by_name_and_kind(
+                        tcx,
+                        binding.ident,
+                        ty::AssocKind::Const,
+                        def_id.to_def_id(),
+                    );
+                    if let Some(assoc_item) = assoc_item {
+                        tcx.type_of(assoc_item.def_id)
+                    } else {
+                        // FIXME(associated_const_equality): add a useful error message here.
+                        tcx.ty_error_with_message(
+                            DUMMY_SP,
+                            "Could not find associated const on trait",
+                        )
+                    }
+                }
+
+                Node::TypeBinding(
+                    binding @ &TypeBinding { hir_id: binding_id, gen_args, ref kind, .. },
+                ) if let Node::TraitRef(trait_ref) =
+                    tcx.hir().get(tcx.hir().get_parent_node(binding_id))
+                    && let Some((idx, _)) =
+                        gen_args.args.iter().enumerate().find(|(_, arg)| {
+                            if let GenericArg::Const(ct) = arg {
+                                ct.value.hir_id == hir_id
+                            } else {
+                                false
+                            }
+                        }) =>
+                {
+                    let Some(trait_def_id) = trait_ref.trait_def_id() else {
+                        return tcx.ty_error_with_message(DUMMY_SP, "Could not find trait");
+                    };
+                    let assoc_items = tcx.associated_items(trait_def_id);
+                    let assoc_item = assoc_items.find_by_name_and_kind(
+                        tcx,
+                        binding.ident,
+                        match kind {
+                            // I think `<A: T>` type bindings requires that `A` is a type
+                            TypeBindingKind::Constraint { .. }
+                            | TypeBindingKind::Equality { term: Term::Ty(..) } => {
+                                ty::AssocKind::Type
+                            }
+                            TypeBindingKind::Equality { term: Term::Const(..) } => {
+                                ty::AssocKind::Const
+                            }
+                        },
+                        def_id.to_def_id(),
+                    );
+                    if let Some(assoc_item) = assoc_item {
+                        tcx.type_of(tcx.generics_of(assoc_item.def_id).params[idx].def_id)
+                    } else {
+                        // FIXME(associated_const_equality): add a useful error message here.
+                        tcx.ty_error_with_message(
+                            DUMMY_SP,
+                            "Could not find associated const on trait",
+                        )
+                    }
                 }
 
                 Node::GenericParam(&GenericParam {
@@ -452,8 +510,7 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                     ..
                 }) if ct.hir_id == hir_id => tcx.type_of(tcx.hir().local_def_id(param_hir_id)),
 
-                x =>
-                  tcx.ty_error_with_message(
+                x => tcx.ty_error_with_message(
                     DUMMY_SP,
                     &format!("unexpected const parent in type_of(): {x:?}"),
                 ),

compiler/rustc_lint/src/builtin.rs

@@ -97,30 +97,28 @@ fn pierce_parens(mut expr: &ast::Expr) -> &ast::Expr {
 
 impl EarlyLintPass for WhileTrue {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
-        if let ast::ExprKind::While(cond, _, label) = &e.kind {
-            if let ast::ExprKind::Lit(ref lit) = pierce_parens(cond).kind {
-                if let ast::LitKind::Bool(true) = lit.kind {
-                    if !lit.span.from_expansion() {
-                        let condition_span = e.span.with_hi(cond.span.hi());
-                        cx.struct_span_lint(WHILE_TRUE, condition_span, |lint| {
-                            lint.build(fluent::lint::builtin_while_true)
-                                .span_suggestion_short(
-                                    condition_span,
-                                    fluent::lint::suggestion,
-                                    format!(
-                                        "{}loop",
-                                        label.map_or_else(String::new, |label| format!(
-                                            "{}: ",
-                                            label.ident,
-                                        ))
-                                    ),
-                                    Applicability::MachineApplicable,
-                                )
-                                .emit();
-                        })
-                    }
-                }
-            }
+        if let ast::ExprKind::While(cond, _, label) = &e.kind
+            && let ast::ExprKind::Lit(ref lit) = pierce_parens(cond).kind
+            && let ast::LitKind::Bool(true) = lit.kind
+            && !lit.span.from_expansion()
+        {
+            let condition_span = e.span.with_hi(cond.span.hi());
+            cx.struct_span_lint(WHILE_TRUE, condition_span, |lint| {
+                lint.build(fluent::lint::builtin_while_true)
+                    .span_suggestion_short(
+                        condition_span,
+                        fluent::lint::suggestion,
+                        format!(
+                            "{}loop",
+                            label.map_or_else(String::new, |label| format!(
+                                "{}: ",
+                                label.ident,
+                            ))
+                        ),
+                        Applicability::MachineApplicable,
+                    )
+                    .emit();
+            })
         }
     }
 }

library/core/src/convert/mod.rs

@@ -440,7 +440,7 @@ pub trait TryInto<T>: Sized {
 ///
 ///     fn try_from(value: i32) -> Result<Self, Self::Error> {
 ///         if value <= 0 {
-///             Err("GreaterThanZero only accepts value superior than zero!")
+///             Err("GreaterThanZero only accepts values greater than zero!")
 ///         } else {
 ///             Ok(GreaterThanZero(value))
 ///         }

library/core/src/iter/traits/iterator.rs

@@ -2431,22 +2431,13 @@ pub trait Iterator {
     ///
     /// # Example
     ///
-    /// Find the maximum value:
-    ///
     /// ```
-    /// fn find_max<I>(iter: I) -> Option<I::Item>
-    ///     where I: Iterator,
-    ///           I::Item: Ord,
-    /// {
-    ///     iter.reduce(|accum, item| {
-    ///         if accum >= item { accum } else { item }
-    ///     })
-    /// }
-    /// let a = [10, 20, 5, -23, 0];
-    /// let b: [u32; 0] = [];
+    /// let reduced: i32 = (1..10).reduce(|acc, e| acc + e).unwrap();
+    /// assert_eq!(reduced, 45);
     ///
-    /// assert_eq!(find_max(a.iter()), Some(&20));
-    /// assert_eq!(find_max(b.iter()), None);
+    /// // Which is equivalent to doing it with `fold`:
+    /// let folded: i32 = (1..10).fold(0, |acc, e| acc + e);
+    /// assert_eq!(reduced, folded);
     /// ```
     #[inline]
     #[stable(feature = "iterator_fold_self", since = "1.51.0")]