Auto merge of #154976 - jhpratt:rollup-e8XWRVU, r=jhpratt

Rollup of 4 pull requests

Successful merges:

 - #154460 (Deduplication: Pulled common logic out from lower_const_arg_struct)
 - #154609 (Enable `#[diagnostic::on_const]` for local impls)
 - #154678 (Introduce #[diagnostic::on_move] on `Rc`)
 - #154902 (rustdoc: Inherit inline attributes for declarative macros)

Author: bors

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -119,6 +119,11 @@ pub struct InherentAssocCandidate {
     pub scope: DefId,
 }
 
+pub struct ResolvedStructPath<'tcx> {
+    pub res: Result<Res, ErrorGuaranteed>,
+    pub ty: Ty<'tcx>,
+}
+
 /// A context which can lower type-system entities from the [HIR][hir] to
 /// the [`rustc_middle::ty`] representation.
 ///
@@ -2618,38 +2623,36 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             ty::Const::new_error(tcx, e)
         };
 
-        let (ty, variant_did) = match qpath {
+        let ResolvedStructPath { res: opt_res, ty } =
+            self.lower_path_for_struct_expr(qpath, span, hir_id);
+
+        let variant_did = match qpath {
             hir::QPath::Resolved(maybe_qself, path) => {
                 debug!(?maybe_qself, ?path);
-                let opt_self_ty = maybe_qself.as_ref().map(|qself| self.lower_ty(qself));
-                let ty =
-                    self.lower_resolved_ty_path(opt_self_ty, path, hir_id, PermitVariants::Yes);
                 let variant_did = match path.res {
                     Res::Def(DefKind::Variant | DefKind::Struct, did) => did,
                     _ => return non_adt_or_variant_res(),
                 };
 
-                (ty, variant_did)
+                variant_did
             }
             hir::QPath::TypeRelative(hir_self_ty, segment) => {
                 debug!(?hir_self_ty, ?segment);
-                let self_ty = self.lower_ty(hir_self_ty);
-                let opt_res = self.lower_type_relative_ty_path(
-                    self_ty,
-                    hir_self_ty,
-                    segment,
-                    hir_id,
-                    span,
-                    PermitVariants::Yes,
-                );
 
-                let (ty, _, res_def_id) = match opt_res {
-                    Ok(r @ (_, DefKind::Variant | DefKind::Struct, _)) => r,
+                let res_def_id = match opt_res {
+                    Ok(r)
+                        if matches!(
+                            tcx.def_kind(r.def_id()),
+                            DefKind::Variant | DefKind::Struct
+                        ) =>
+                    {
+                        r.def_id()
+                    }
                     Ok(_) => return non_adt_or_variant_res(),
                     Err(e) => return ty::Const::new_error(tcx, e),
                 };
 
-                (ty, res_def_id)
+                res_def_id
             }
         };
 
@@ -2710,6 +2713,41 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         ty::Const::new_value(tcx, valtree, ty)
     }
 
+    pub fn lower_path_for_struct_expr(
+        &self,
+        qpath: hir::QPath<'tcx>,
+        path_span: Span,
+        hir_id: HirId,
+    ) -> ResolvedStructPath<'tcx> {
+        match qpath {
+            hir::QPath::Resolved(ref maybe_qself, path) => {
+                let self_ty = maybe_qself.as_ref().map(|qself| self.lower_ty(qself));
+                let ty = self.lower_resolved_ty_path(self_ty, path, hir_id, PermitVariants::Yes);
+                ResolvedStructPath { res: Ok(path.res), ty }
+            }
+            hir::QPath::TypeRelative(hir_self_ty, segment) => {
+                let self_ty = self.lower_ty(hir_self_ty);
+
+                let result = self.lower_type_relative_ty_path(
+                    self_ty,
+                    hir_self_ty,
+                    segment,
+                    hir_id,
+                    path_span,
+                    PermitVariants::Yes,
+                );
+                let ty = result
+                    .map(|(ty, _, _)| ty)
+                    .unwrap_or_else(|guar| Ty::new_error(self.tcx(), guar));
+
+                ResolvedStructPath {
+                    res: result.map(|(_, kind, def_id)| Res::Def(kind, def_id)),
+                    ty,
+                }
+            }
+        }
+    }
+
     /// Lower a [resolved][hir::QPath::Resolved] path to a (type-level) constant.
     fn lower_resolved_const_path(
         &self,

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -13,7 +13,7 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::{Expr, ExprKind, FnRetTy, HirId, LangItem, Node, QPath, is_range_literal};
 use rustc_hir_analysis::check::potentially_plural_count;
-use rustc_hir_analysis::hir_ty_lowering::{HirTyLowerer, PermitVariants};
+use rustc_hir_analysis::hir_ty_lowering::{HirTyLowerer, ResolvedStructPath};
 use rustc_index::IndexVec;
 use rustc_infer::infer::{BoundRegionConversionTime, DefineOpaqueTypes, InferOk, TypeTrace};
 use rustc_middle::ty::adjustment::AllowTwoPhase;
@@ -1265,38 +1265,19 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         path_span: Span,
         hir_id: HirId,
     ) -> (Res, LoweredTy<'tcx>) {
+        let ResolvedStructPath { res: result, ty } =
+            self.lowerer().lower_path_for_struct_expr(*qpath, path_span, hir_id);
         match *qpath {
-            QPath::Resolved(ref maybe_qself, path) => {
-                let self_ty = maybe_qself.as_ref().map(|qself| self.lower_ty(qself).raw);
-                let ty = self.lowerer().lower_resolved_ty_path(
-                    self_ty,
-                    path,
-                    hir_id,
-                    PermitVariants::Yes,
-                );
-                (path.res, LoweredTy::from_raw(self, path_span, ty))
-            }
-            QPath::TypeRelative(hir_self_ty, segment) => {
-                let self_ty = self.lower_ty(hir_self_ty);
-
-                let result = self.lowerer().lower_type_relative_ty_path(
-                    self_ty.raw,
-                    hir_self_ty,
-                    segment,
-                    hir_id,
-                    path_span,
-                    PermitVariants::Yes,
-                );
-                let ty = result
-                    .map(|(ty, _, _)| ty)
-                    .unwrap_or_else(|guar| Ty::new_error(self.tcx(), guar));
+            QPath::Resolved(_, path) => (path.res, LoweredTy::from_raw(self, path_span, ty)),
+            QPath::TypeRelative(_, _) => {
                 let ty = LoweredTy::from_raw(self, path_span, ty);
-                let result = result.map(|(_, kind, def_id)| (kind, def_id));
+                let resolution =
+                    result.map(|res: Res| (self.tcx().def_kind(res.def_id()), res.def_id()));
 
                 // Write back the new resolution.
-                self.write_resolution(hir_id, result);
+                self.write_resolution(hir_id, resolution);
 
-                (result.map_or(Res::Err, |(kind, def_id)| Res::Def(kind, def_id)), ty)
+                (result.unwrap_or(Res::Err), ty)
             }
         }
     }

compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs

@@ -882,55 +882,46 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
             let trait_name = self.tcx.item_name(trait_did);
 
             if self.tcx.is_const_trait(trait_did) && !self.tcx.is_const_trait_impl(impl_did) {
-                if let Some(impl_did) = impl_did.as_local()
-                    && let item = self.tcx.hir_expect_item(impl_did)
-                    && let hir::ItemKind::Impl(item) = item.kind
-                    && let Some(of_trait) = item.of_trait
-                {
-                    // trait is const, impl is local and not const
-                    diag.span_suggestion_verbose(
-                        of_trait.trait_ref.path.span.shrink_to_lo(),
-                        format!("make the `impl` of trait `{trait_name}` `const`"),
-                        "const ".to_string(),
-                        Applicability::MaybeIncorrect,
-                    );
-                } else {
+                if !impl_did.is_local() {
                     diag.span_note(
                         impl_span,
                         format!("trait `{trait_name}` is implemented but not `const`"),
                     );
+                }
 
-                    let (condition_options, format_args) = self.on_unimplemented_components(
+                if let Some(command) =
+                    find_attr!(self.tcx, impl_did, OnConst {directive, ..} => directive.as_deref())
+                        .flatten()
+                {
+                    let (_, format_args) = self.on_unimplemented_components(
                         trait_ref,
                         main_obligation,
                         diag.long_ty_path(),
                     );
+                    let CustomDiagnostic { message, label, notes, parent_label: _ } =
+                        command.eval(None, &format_args);
 
-                    if let Some(command) = find_attr!(self.tcx, impl_did, OnConst {directive, ..} => directive.as_deref()).flatten(){
-                        let note = command.eval(
-                            Some(&condition_options),
-                            &format_args,
-                        );
-                        let CustomDiagnostic {
-                            message,
-                            label,
-                            notes,
-                            parent_label,
-                        } = note;
-
-                        if let Some(message) = message {
-                            diag.primary_message(message);
-                        }
-                        if let Some(label) = label {
-                            diag.span_label(impl_span, label);
-                        }
-                        for note in notes {
-                            diag.note(note);
-                        }
-                        if let Some(parent_label) = parent_label {
-                            diag.span_label(impl_span, parent_label);
-                        }
+                    if let Some(message) = message {
+                        diag.primary_message(message);
+                    }
+                    if let Some(label) = label {
+                        diag.span_label(span, label);
+                    }
+                    for note in notes {
+                        diag.note(note);
                     }
+                } else if let Some(impl_did) = impl_did.as_local()
+                    && let item = self.tcx.hir_expect_item(impl_did)
+                    && let hir::ItemKind::Impl(item) = item.kind
+                    && let Some(of_trait) = item.of_trait
+                {
+                    // trait is const, impl is local and not const
+                    diag.span_suggestion_verbose(
+                        of_trait.trait_ref.path.span.shrink_to_lo(),
+                        format!("make the `impl` of trait `{trait_name}` `const`"),
+                        "const ".to_string(),
+                        Applicability::MaybeIncorrect,
+                    );
                 }
             }
         }

library/alloc/src/rc.rs

@@ -311,6 +311,12 @@ fn rc_inner_layout_for_value_layout(layout: Layout) -> Layout {
 #[rustc_diagnostic_item = "Rc"]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_insignificant_dtor]
+#[diagnostic::on_move(
+    message = "the type `{Self}` does not implement `Copy`",
+    label = "this move could be avoided by cloning the original `{Self}`, which is inexpensive",
+    note = "consider using `Rc::clone`"
+)]
+
 pub struct Rc<
     T: ?Sized,
     #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global,

src/librustdoc/clean/mod.rs

@@ -176,6 +176,35 @@ fn is_glob_import(tcx: TyCtxt<'_>, import_id: LocalDefId) -> bool {
     }
 }
 
+/// Returns true if `def_id` is a macro and should be inlined.
+pub(crate) fn macro_reexport_is_inline(
+    tcx: TyCtxt<'_>,
+    import_id: LocalDefId,
+    def_id: DefId,
+) -> bool {
+    if !matches!(tcx.def_kind(def_id), DefKind::Macro(MacroKinds::BANG)) {
+        return false;
+    }
+
+    for reexport_def_id in reexport_chain(tcx, import_id, def_id).iter().flat_map(|r| r.id()) {
+        let is_hidden = tcx.is_doc_hidden(reexport_def_id);
+        let is_inline = find_attr!(
+            inline::load_attrs(tcx, reexport_def_id),
+            Doc(d)
+            if d.inline.first().is_some_and(|(inline, _)| *inline == DocInline::Inline)
+        );
+
+        // hidden takes absolute priority over inline on the same node
+        if is_hidden {
+            return false;
+        }
+        if is_inline {
+            return true;
+        }
+    }
+    false
+}
+
 fn generate_item_with_correct_attrs(
     cx: &mut DocContext<'_>,
     kind: ItemKind,
@@ -201,7 +230,8 @@ fn generate_item_with_correct_attrs(
                 Doc(d)
                 if d.inline.first().is_some_and(|(inline, _)| *inline == DocInline::Inline)
             ) || (is_glob_import(tcx, import_id)
-                && (cx.document_hidden() || !tcx.is_doc_hidden(def_id)));
+                && (cx.document_hidden() || !tcx.is_doc_hidden(def_id)))
+                || macro_reexport_is_inline(tcx, import_id, def_id);
             attrs.extend(get_all_import_attributes(cx, import_id, def_id, is_inline));
             is_inline = is_inline || import_is_inline;
         }

src/librustdoc/visit_ast.rs

@@ -478,11 +478,21 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
                     // If there was a private module in the current path then don't bother inlining
                     // anything as it will probably be stripped anyway.
                     if is_pub && self.inside_public_path {
-                        let please_inline = find_attr!(
-                            attrs,
-                            Doc(d)
-                            if d.inline.first().is_some_and(|(inline, _)| *inline == DocInline::Inline)
-                        );
+                        let please_inline = if let Some(res_did) = res.opt_def_id()
+                            && matches!(tcx.def_kind(res_did), DefKind::Macro(MacroKinds::BANG))
+                        {
+                            crate::clean::macro_reexport_is_inline(
+                                tcx,
+                                item.owner_id.def_id,
+                                res_did,
+                            )
+                        } else {
+                            find_attr!(
+                                attrs,
+                                Doc(d)
+                                if d.inline.first().is_some_and(|(inline, _)| *inline == DocInline::Inline)
+                            )
+                        };
                         let ident = match kind {
                             hir::UseKind::Single(ident) => Some(ident.name),
                             hir::UseKind::Glob => None,