Rollup of 8 pull requests

.mailmap

@@ -543,6 +543,7 @@ Takashi Idobe <idobetakashi@gmail.com>
 Takayuki Maeda <takoyaki0316@gmail.com>
 Tamir Duberstein <tamird@gmail.com> Tamir Duberstein <tamird@squareup.com>
 Tatsuyuki Ishi <ishitatsuyuki@gmail.com>
+Tau Gärtli <git@tau.garden> <ruben.schmidmeister@icloud.com>
 Tero Hänninen <lgvz@users.noreply.github.com> Tero Hänninen <tejohann@kapsi.fi>
 The8472 <git@infinite-source.de>
 Theo Belaire <theo.belaire@gmail.com> Theo Belaire <tyr.god.of.war.42@gmail.com>

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -21,7 +21,7 @@ use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt;
 
 use crate::diagnostics::BorrowedContentSource;
 use crate::util::FindAssignments;
-use crate::MirBorrowckCtxt;
+use crate::{session_diagnostics, MirBorrowckCtxt};
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub(crate) enum AccessKind {
@@ -234,7 +234,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         Some(mir::BorrowKind::Mut { kind: mir::MutBorrowKind::Default }),
                         |_kind, var_span| {
                             let place = self.describe_any_place(access_place.as_ref());
-                            crate::session_diagnostics::CaptureVarCause::MutableBorrowUsePlaceClosure {
+                            session_diagnostics::CaptureVarCause::MutableBorrowUsePlaceClosure {
                                 place,
                                 var_span,
                             }
@@ -667,19 +667,26 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     /// User cannot make signature of a trait mutable without changing the
     /// trait. So we find if this error belongs to a trait and if so we move
     /// suggestion to the trait or disable it if it is out of scope of this crate
-    fn is_error_in_trait(&self, local: Local) -> (bool, Option<Span>) {
+    ///
+    /// The returned values are:
+    ///  - is the current item an assoc `fn` of an impl that corresponds to a trait def? if so, we
+    ///    have to suggest changing both the impl `fn` arg and the trait `fn` arg
+    ///  - is the trait from the local crate? If not, we can't suggest changing signatures
+    ///  - `Span` of the argument in the trait definition
+    fn is_error_in_trait(&self, local: Local) -> (bool, bool, Option<Span>) {
         if self.body.local_kind(local) != LocalKind::Arg {
-            return (false, None);
+            return (false, false, None);
         }
         let my_def = self.body.source.def_id();
         let my_hir = self.infcx.tcx.local_def_id_to_hir_id(my_def.as_local().unwrap());
         let Some(td) =
             self.infcx.tcx.impl_of_method(my_def).and_then(|x| self.infcx.tcx.trait_id_of_impl(x))
         else {
-            return (false, None);
+            return (false, false, None);
         };
         (
             true,
+            td.is_local(),
             td.as_local().and_then(|tld| match self.infcx.tcx.hir_node_by_def_id(tld) {
                 Node::Item(hir::Item { kind: hir::ItemKind::Trait(_, _, _, _, items), .. }) => {
                     let mut f_in_trait_opt = None;
@@ -695,19 +702,16 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         break;
                     }
                     f_in_trait_opt.and_then(|f_in_trait| {
-                        match self.infcx.tcx.hir_node(f_in_trait) {
-                            Node::TraitItem(hir::TraitItem {
-                                kind:
-                                    hir::TraitItemKind::Fn(
-                                        hir::FnSig { decl: hir::FnDecl { inputs, .. }, .. },
-                                        _,
-                                    ),
-                                ..
-                            }) => {
-                                let hir::Ty { span, .. } = *inputs.get(local.index() - 1)?;
-                                Some(span)
-                            }
-                            _ => None,
+                        if let Node::TraitItem(ti) = self.infcx.tcx.hir_node(f_in_trait)
+                            && let hir::TraitItemKind::Fn(sig, _) = ti.kind
+                            && let Some(ty) = sig.decl.inputs.get(local.index() - 1)
+                            && let hir::TyKind::Ref(_, mut_ty) = ty.kind
+                            && let hir::Mutability::Not = mut_ty.mutbl
+                            && sig.decl.implicit_self.has_implicit_self()
+                        {
+                            Some(ty.span)
+                        } else {
+                            None
                         }
                     })
                 }
@@ -1061,20 +1065,24 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         let (pointer_sigil, pointer_desc) =
             if local_decl.ty.is_ref() { ("&", "reference") } else { ("*const", "pointer") };
 
-        let (is_trait_sig, local_trait) = self.is_error_in_trait(local);
-        if is_trait_sig && local_trait.is_none() {
+        let (is_trait_sig, is_local, local_trait) = self.is_error_in_trait(local);
+
+        if is_trait_sig && !is_local {
+            // Do not suggest to change the signature when the trait comes from another crate.
+            err.span_label(
+                local_decl.source_info.span,
+                format!("this is an immutable {pointer_desc}"),
+            );
             return;
         }
-
-        let decl_span = match local_trait {
-            Some(span) => span,
-            None => local_decl.source_info.span,
-        };
+        let decl_span = local_decl.source_info.span;
 
         let label = match *local_decl.local_info() {
             LocalInfo::User(mir::BindingForm::ImplicitSelf(_)) => {
                 let suggestion = suggest_ampmut_self(self.infcx.tcx, decl_span);
-                Some((true, decl_span, suggestion))
+                let additional =
+                    local_trait.map(|span| (span, suggest_ampmut_self(self.infcx.tcx, span)));
+                Some((true, decl_span, suggestion, additional))
             }
 
             LocalInfo::User(mir::BindingForm::Var(mir::VarBindingForm {
@@ -1113,7 +1121,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     // don't create labels for compiler-generated spans
                     Some(_) => None,
                     None => {
-                        let label = if name != kw::SelfLower {
+                        let (has_sugg, decl_span, sugg) = if name != kw::SelfLower {
                             suggest_ampmut(
                                 self.infcx.tcx,
                                 local_decl.ty,
@@ -1140,7 +1148,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                 ),
                             }
                         };
-                        Some(label)
+                        Some((has_sugg, decl_span, sugg, None))
                     }
                 }
             }
@@ -1151,22 +1159,33 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             })) => {
                 let pattern_span: Span = local_decl.source_info.span;
                 suggest_ref_mut(self.infcx.tcx, pattern_span)
-                    .map(|span| (true, span, "mut ".to_owned()))
+                    .map(|span| (true, span, "mut ".to_owned(), None))
             }
 
             _ => unreachable!(),
         };
 
         match label {
-            Some((true, err_help_span, suggested_code)) => {
-                err.span_suggestion_verbose(
-                    err_help_span,
-                    format!("consider changing this to be a mutable {pointer_desc}"),
-                    suggested_code,
+            Some((true, err_help_span, suggested_code, additional)) => {
+                let mut sugg = vec![(err_help_span, suggested_code)];
+                if let Some(s) = additional {
+                    sugg.push(s);
+                }
+
+                err.multipart_suggestion_verbose(
+                    format!(
+                        "consider changing this to be a mutable {pointer_desc}{}",
+                        if is_trait_sig {
+                            " in the `impl` method and the `trait` definition"
+                        } else {
+                            ""
+                        }
+                    ),
+                    sugg,
                     Applicability::MachineApplicable,
                 );
             }
-            Some((false, err_label_span, message)) => {
+            Some((false, err_label_span, message, _)) => {
                 let def_id = self.body.source.def_id();
                 let hir_id = if let Some(local_def_id) = def_id.as_local()
                     && let Some(body_id) = self.infcx.tcx.hir().maybe_body_owned_by(local_def_id)

compiler/rustc_hir_typeck/src/coercion.rs

@@ -2004,16 +2004,17 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
             }
         }
 
-        let parent_id = fcx.tcx.hir().get_parent_item(id);
-        let mut parent_item = fcx.tcx.hir_node_by_def_id(parent_id.def_id);
+        let mut parent_id = fcx.tcx.hir().get_parent_item(id).def_id;
+        let mut parent_item = fcx.tcx.hir_node_by_def_id(parent_id);
         // When suggesting return, we need to account for closures and async blocks, not just items.
         for (_, node) in fcx.tcx.hir().parent_iter(id) {
             match node {
                 hir::Node::Expr(&hir::Expr {
-                    kind: hir::ExprKind::Closure(hir::Closure { .. }),
+                    kind: hir::ExprKind::Closure(hir::Closure { def_id, .. }),
                     ..
                 }) => {
                     parent_item = node;
+                    parent_id = *def_id;
                     break;
                 }
                 hir::Node::Item(_) | hir::Node::TraitItem(_) | hir::Node::ImplItem(_) => break,
@@ -2023,13 +2024,7 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
 
         if let (Some(expr), Some(_), Some(fn_decl)) = (expression, blk_id, parent_item.fn_decl()) {
             fcx.suggest_missing_break_or_return_expr(
-                &mut err,
-                expr,
-                fn_decl,
-                expected,
-                found,
-                id,
-                parent_id.into(),
+                &mut err, expr, fn_decl, expected, found, id, parent_id,
             );
         }
 

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -942,7 +942,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub(in super::super) fn get_node_fn_decl(
         &self,
         node: Node<'tcx>,
-    ) -> Option<(hir::HirId, &'tcx hir::FnDecl<'tcx>, Ident, bool)> {
+    ) -> Option<(LocalDefId, &'tcx hir::FnDecl<'tcx>, Ident, bool)> {
         match node {
             Node::Item(&hir::Item {
                 ident,
@@ -953,25 +953,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // This is less than ideal, it will not suggest a return type span on any
                 // method called `main`, regardless of whether it is actually the entry point,
                 // but it will still present it as the reason for the expected type.
-                Some((
-                    hir::HirId::make_owner(owner_id.def_id),
-                    &sig.decl,
-                    ident,
-                    ident.name != sym::main,
-                ))
+                Some((owner_id.def_id, &sig.decl, ident, ident.name != sym::main))
             }
             Node::TraitItem(&hir::TraitItem {
                 ident,
                 kind: hir::TraitItemKind::Fn(ref sig, ..),
                 owner_id,
                 ..
-            }) => Some((hir::HirId::make_owner(owner_id.def_id), &sig.decl, ident, true)),
+            }) => Some((owner_id.def_id, &sig.decl, ident, true)),
             Node::ImplItem(&hir::ImplItem {
                 ident,
                 kind: hir::ImplItemKind::Fn(ref sig, ..),
                 owner_id,
                 ..
-            }) => Some((hir::HirId::make_owner(owner_id.def_id), &sig.decl, ident, false)),
+            }) => Some((owner_id.def_id, &sig.decl, ident, false)),
             Node::Expr(&hir::Expr {
                 hir_id,
                 kind:
@@ -1001,12 +996,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     }) => (ident, sig, owner_id),
                     _ => return None,
                 };
-                Some((
-                    hir::HirId::make_owner(owner_id.def_id),
-                    &sig.decl,
-                    ident,
-                    ident.name != sym::main,
-                ))
+                Some((owner_id.def_id, &sig.decl, ident, ident.name != sym::main))
             }
             _ => None,
         }
@@ -1017,7 +1007,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn get_fn_decl(
         &self,
         blk_id: hir::HirId,
-    ) -> Option<(hir::HirId, &'tcx hir::FnDecl<'tcx>, bool)> {
+    ) -> Option<(LocalDefId, &'tcx hir::FnDecl<'tcx>, bool)> {
         // Get enclosing Fn, if it is a function or a trait method, unless there's a `loop` or
         // `while` before reaching it, as block tail returns are not available in them.
         self.tcx.hir().get_return_block(blk_id).and_then(|blk_id| {

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -9,6 +9,7 @@ use crate::method::probe::{IsSuggestion, Mode, ProbeScope};
 use crate::rustc_middle::ty::Article;
 use core::cmp::min;
 use core::iter;
+use hir::def_id::LocalDefId;
 use rustc_ast::util::parser::{ExprPrecedence, PREC_POSTFIX};
 use rustc_data_structures::packed::Pu128;
 use rustc_errors::{Applicability, Diag, MultiSpan};
@@ -796,7 +797,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
         can_suggest: bool,
-        fn_id: hir::HirId,
+        fn_id: LocalDefId,
     ) -> bool {
         let found =
             self.resolve_numeric_literals_with_default(self.resolve_vars_if_possible(found));
@@ -923,7 +924,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         err: &mut Diag<'_>,
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
-        fn_id: hir::HirId,
+        fn_id: LocalDefId,
     ) {
         // Only apply the suggestion if:
         //  - the return type is a generic parameter
@@ -937,7 +938,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let ty::Param(expected_ty_as_param) = expected.kind() else { return };
 
-        let fn_node = self.tcx.hir_node(fn_id);
+        let fn_node = self.tcx.hir_node_by_def_id(fn_id);
 
         let hir::Node::Item(hir::Item {
             kind:
@@ -1031,7 +1032,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
         id: hir::HirId,
-        fn_id: hir::HirId,
+        fn_id: LocalDefId,
     ) {
         if !expected.is_unit() {
             return;
@@ -1083,11 +1084,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let can_return = match fn_decl.output {
             hir::FnRetTy::Return(ty) => {
                 let ty = self.lowerer().lower_ty(ty);
-                let bound_vars = self.tcx.late_bound_vars(fn_id);
+                let bound_vars = self.tcx.late_bound_vars(self.tcx.local_def_id_to_hir_id(fn_id));
                 let ty = self
                     .tcx
                     .instantiate_bound_regions_with_erased(Binder::bind_with_vars(ty, bound_vars));
-                let ty = match self.tcx.asyncness(fn_id.owner) {
+                let ty = match self.tcx.asyncness(fn_id) {
                     ty::Asyncness::Yes => self.get_impl_future_output_ty(ty).unwrap_or_else(|| {
                         span_bug!(
                             fn_decl.output.span(),
@@ -1108,8 +1109,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             _ => false,
         };
         if can_return
-            && let Some(owner_node) = self.tcx.hir_node(fn_id).as_owner()
-            && let Some(span) = expr.span.find_ancestor_inside(*owner_node.span())
+            && let Some(span) = expr.span.find_ancestor_inside(
+                self.tcx.hir().span_with_body(self.tcx.local_def_id_to_hir_id(fn_id)),
+            )
         {
             err.multipart_suggestion(
                 "you might have meant to return this value",

compiler/rustc_resolve/src/imports.rs

@@ -1391,13 +1391,15 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             let mut redundant_spans: Vec<_> = redundant_span.present_items().collect();
             redundant_spans.sort();
             redundant_spans.dedup();
+            /* FIXME(unused_imports): Add this back as a new lint
             self.lint_buffer.buffer_lint_with_diagnostic(
                 UNUSED_IMPORTS,
                 id,
                 import.span,
                 format!("the item `{source}` is imported redundantly"),
                 BuiltinLintDiag::RedundantImport(redundant_spans, source),
             );
+            */
             return true;
         }
 

compiler/rustc_resolve/src/lib.rs

@@ -177,7 +177,7 @@ enum ImplTraitContext {
 
 /// Used for tracking import use types which will be used for redundant import checking.
 /// ### Used::Scope Example
-///  ```rust,compile_fail
+///  ```rust,ignore (redundant_imports)
 /// #![deny(unused_imports)]
 /// use std::mem::drop;
 /// fn main() {

library/core/src/io/borrowed_buf.rs

@@ -249,9 +249,10 @@ impl<'a> BorrowedCursor<'a> {
     /// Panics if there are less than `n` bytes initialized.
     #[inline]
     pub fn advance(&mut self, n: usize) -> &mut Self {
-        assert!(self.buf.init >= self.buf.filled + n);
+        let filled = self.buf.filled.strict_add(n);
+        assert!(filled <= self.buf.init);
 
-        self.buf.filled += n;
+        self.buf.filled = filled;
         self
     }