Auto merge of rust-lang#136135 - GuillaumeGomez:rollup-1ik636d, r=GuillaumeGomez

Rollup of 10 pull requests

Successful merges:

 - rust-lang#135773 (Clarify WindowsMut (Lending)Iterator)
 - rust-lang#135807 (Implement phantom variance markers)
 - rust-lang#135876 (fix doc for std::sync::mpmc)
 - rust-lang#135988 (Add a workaround for parallel rustc crashing when there are delayed bugs)
 - rust-lang#136037 (Mark all NuttX targets as tier 3 target and support the standard library)
 - rust-lang#136064 (Add a suggestion to cast target_feature fn items to fn pointers.)
 - rust-lang#136082 (Incorporate `iter_nodes` into `graph::DirectedGraph`)
 - rust-lang#136112 (Clean up all dead files inside `tests/ui/`)
 - rust-lang#136114 (Use identifiers more in diagnostics code)
 - rust-lang#136118 (Change `collect_and_partition_mono_items` tuple return type to a struct)

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

Author: bors

Diff for: compiler/rustc_builtin_macros/src/deriving/coerce_pointee.rs

@@ -157,7 +157,7 @@ pub(crate) fn expand_deriving_coerce_pointee(
         {
             cx.dcx().emit_err(RequiresMaybeSized {
                 span: pointee_ty_ident.span,
-                name: pointee_ty_ident.name.to_ident_string(),
+                name: pointee_ty_ident,
             });
             return;
         }
@@ -471,5 +471,5 @@ struct TooManyPointees {
 struct RequiresMaybeSized {
     #[primary_span]
     span: Span,
-    name: String,
+    name: Ident,
 }

Diff for: compiler/rustc_codegen_cranelift/src/driver/aot.rs

@@ -676,7 +676,7 @@ pub(crate) fn run_aot(
     .to_owned();
 
     let cgus = if tcx.sess.opts.output_types.should_codegen() {
-        tcx.collect_and_partition_mono_items(()).1
+        tcx.collect_and_partition_mono_items(()).codegen_units
     } else {
         // If only `--emit metadata` is used, we shouldn't perform any codegen.
         // Also `tcx.collect_and_partition_mono_items` may panic in that case.

Diff for: compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -9,6 +9,7 @@ use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_index::IndexVec;
 use rustc_middle::mir;
+use rustc_middle::mir::mono::MonoItemPartitions;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::RemapFileNameExt;
 use rustc_session::config::RemapPathScopeComponents;
@@ -297,12 +298,13 @@ struct UsageSets<'tcx> {
 /// Prepare sets of definitions that are relevant to deciding whether something
 /// is an "unused function" for coverage purposes.
 fn prepare_usage_sets<'tcx>(tcx: TyCtxt<'tcx>) -> UsageSets<'tcx> {
-    let (all_mono_items, cgus) = tcx.collect_and_partition_mono_items(());
+    let MonoItemPartitions { all_mono_items, codegen_units } =
+        tcx.collect_and_partition_mono_items(());
 
     // Obtain a MIR body for each function participating in codegen, via an
     // arbitrary instance.
     let mut def_ids_seen = FxHashSet::default();
-    let def_and_mir_for_all_mono_fns = cgus
+    let def_and_mir_for_all_mono_fns = codegen_units
         .iter()
         .flat_map(|cgu| cgu.items().keys())
         .filter_map(|item| match item {

Diff for: compiler/rustc_codegen_ssa/src/assert_module_sources.rs

@@ -46,8 +46,12 @@ pub fn assert_module_sources(tcx: TyCtxt<'_>, set_reuse: &dyn Fn(&mut CguReuseTr
             return;
         }
 
-        let available_cgus =
-            tcx.collect_and_partition_mono_items(()).1.iter().map(|cgu| cgu.name()).collect();
+        let available_cgus = tcx
+            .collect_and_partition_mono_items(())
+            .codegen_units
+            .iter()
+            .map(|cgu| cgu.name())
+            .collect();
 
         let mut ams = AssertModuleSource {
             tcx,

Diff for: compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -293,7 +293,7 @@ fn exported_symbols_provider_local(
         // external linkage is enough for monomorphization to be linked to.
         let need_visibility = tcx.sess.target.dynamic_linking && !tcx.sess.target.only_cdylib;
 
-        let (_, cgus) = tcx.collect_and_partition_mono_items(());
+        let cgus = tcx.collect_and_partition_mono_items(()).codegen_units;
 
         // The symbols created in this loop are sorted below it
         #[allow(rustc::potential_query_instability)]

Diff for: compiler/rustc_codegen_ssa/src/base.rs

@@ -619,7 +619,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
 
     // Run the monomorphization collector and partition the collected items into
     // codegen units.
-    let codegen_units = tcx.collect_and_partition_mono_items(()).1;
+    let codegen_units = tcx.collect_and_partition_mono_items(()).codegen_units;
 
     // Force all codegen_unit queries so they are already either red or green
     // when compile_codegen_unit accesses them. We are not able to re-execute
@@ -1051,7 +1051,7 @@ pub(crate) fn provide(providers: &mut Providers) {
             config::OptLevel::SizeMin => config::OptLevel::Default,
         };
 
-        let (defids, _) = tcx.collect_and_partition_mono_items(cratenum);
+        let defids = tcx.collect_and_partition_mono_items(cratenum).all_mono_items;
 
         let any_for_speed = defids.items().any(|id| {
             let CodegenFnAttrs { optimize, .. } = tcx.codegen_fn_attrs(*id);

Diff for: compiler/rustc_data_structures/src/graph/mod.rs

@@ -14,7 +14,23 @@ mod tests;
 pub trait DirectedGraph {
     type Node: Idx;
 
+    /// Returns the total number of nodes in this graph.
+    ///
+    /// Several graph algorithm implementations assume that every node ID is
+    /// strictly less than the number of nodes, i.e. nodes are densely numbered.
+    /// That assumption allows them to use `num_nodes` to allocate per-node
+    /// data structures, indexed by node.
     fn num_nodes(&self) -> usize;
+
+    /// Iterates over all nodes of a graph in ascending numeric order.
+    ///
+    /// Assumes that nodes are densely numbered, i.e. every index in
+    /// `0..num_nodes` is a valid node.
+    fn iter_nodes(
+        &self,
+    ) -> impl Iterator<Item = Self::Node> + DoubleEndedIterator + ExactSizeIterator {
+        (0..self.num_nodes()).map(<Self::Node as Idx>::new)
+    }
 }
 
 pub trait NumEdges: DirectedGraph {

Diff for: compiler/rustc_data_structures/src/graph/scc/mod.rs

@@ -333,8 +333,8 @@ where
             to_annotation,
         };
 
-        let scc_indices = (0..num_nodes)
-            .map(G::Node::new)
+        let scc_indices = graph
+            .iter_nodes()
             .map(|node| match this.start_walk_from(node) {
                 WalkReturn::Complete { scc_index, .. } => scc_index,
                 WalkReturn::Cycle { min_depth, .. } => {

Diff for: compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -2362,7 +2362,7 @@ fn try_report_async_mismatch<'tcx>(
             // the right span is a bit difficult.
             return Err(tcx.sess.dcx().emit_err(MethodShouldReturnFuture {
                 span: tcx.def_span(impl_m.def_id),
-                method_name: trait_m.name,
+                method_name: tcx.item_ident(impl_m.def_id),
                 trait_item_span: tcx.hir().span_if_local(trait_m.def_id),
             }));
         }

Diff for: compiler/rustc_hir_analysis/src/check/mod.rs

@@ -197,7 +197,7 @@ fn maybe_check_static_with_link_section(tcx: TyCtxt<'_>, id: LocalDefId) {
 
 fn report_forbidden_specialization(tcx: TyCtxt<'_>, impl_item: DefId, parent_impl: DefId) {
     let span = tcx.def_span(impl_item);
-    let ident = tcx.item_name(impl_item);
+    let ident = tcx.item_ident(impl_item);
 
     let err = match tcx.span_of_impl(parent_impl) {
         Ok(sp) => errors::ImplNotMarkedDefault::Ok { span, ident, ok_label: sp },
@@ -297,7 +297,7 @@ fn default_body_is_unstable(
     reason: Option<Symbol>,
     issue: Option<NonZero<u32>>,
 ) {
-    let missing_item_name = tcx.associated_item(item_did).name;
+    let missing_item_name = tcx.item_ident(item_did);
     let (mut some_note, mut none_note, mut reason_str) = (false, false, String::new());
     match reason {
         Some(r) => {

Diff for: compiler/rustc_hir_analysis/src/coherence/builtin.rs

@@ -292,7 +292,7 @@ fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<()
 
                         res = Err(tcx.dcx().emit_err(errors::DispatchFromDynZST {
                             span,
-                            name: field.name,
+                            name: field.ident(tcx),
                             ty: ty_a,
                         }));
 

Diff for: compiler/rustc_hir_analysis/src/coherence/orphan.rs

@@ -465,8 +465,8 @@ fn emit_orphan_check_error<'tcx>(
         traits::OrphanCheckErr::UncoveredTyParams(UncoveredTyParams { uncovered, local_ty }) => {
             let mut reported = None;
             for param_def_id in uncovered {
-                let span = tcx.def_ident_span(param_def_id).unwrap();
-                let name = tcx.item_name(param_def_id);
+                let name = tcx.item_ident(param_def_id);
+                let span = name.span;
 
                 reported.get_or_insert(match local_ty {
                     Some(local_type) => tcx.dcx().emit_err(errors::TyParamFirstLocal {
@@ -492,7 +492,7 @@ fn lint_uncovered_ty_params<'tcx>(
 
     for param_def_id in uncovered {
         let span = tcx.def_ident_span(param_def_id).unwrap();
-        let name = tcx.item_name(param_def_id);
+        let name = tcx.item_ident(param_def_id);
 
         match local_ty {
             Some(local_type) => tcx.emit_node_span_lint(

Diff for: compiler/rustc_hir_analysis/src/collect.rs

@@ -928,7 +928,7 @@ fn lower_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId) {
                 tcx.dcx().emit_err(errors::EnumDiscriminantOverflowed {
                     span,
                     discr: prev_discr.unwrap().to_string(),
-                    item_name: tcx.item_name(variant.def_id),
+                    item_name: tcx.item_ident(variant.def_id),
                     wrapped_discr: wrapped_discr.to_string(),
                 });
                 None
@@ -990,11 +990,10 @@ impl<'tcx> FieldUniquenessCheckContext<'tcx> {
     }
 
     /// Check if a given field `ident` declared at `field_decl` has been declared elsewhere before.
-    fn check_field_decl(&mut self, ident: Ident, field_decl: FieldDeclSpan) {
+    fn check_field_decl(&mut self, field_name: Ident, field_decl: FieldDeclSpan) {
         use FieldDeclSpan::*;
-        let field_name = ident.name;
-        let ident = ident.normalize_to_macros_2_0();
-        match (field_decl, self.seen_fields.get(&ident).copied()) {
+        let field_name = field_name.normalize_to_macros_2_0();
+        match (field_decl, self.seen_fields.get(&field_name).copied()) {
             (NotNested(span), Some(NotNested(prev_span))) => {
                 self.tcx.dcx().emit_err(errors::FieldAlreadyDeclared::NotNested {
                     field_name,
@@ -1035,7 +1034,7 @@ impl<'tcx> FieldUniquenessCheckContext<'tcx> {
                 });
             }
             (field_decl, None) => {
-                self.seen_fields.insert(ident, field_decl);
+                self.seen_fields.insert(field_name, field_decl);
             }
         }
     }

Diff for: compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs

@@ -55,7 +55,7 @@ pub(super) fn find_opaque_ty_constraints_for_impl_trait_in_assoc_type(
     } else {
         let reported = tcx.dcx().emit_err(UnconstrainedOpaqueType {
             span: tcx.def_span(def_id),
-            name: tcx.item_name(parent_def_id.to_def_id()),
+            name: tcx.item_ident(parent_def_id.to_def_id()),
             what: "impl",
         });
         Ty::new_error(tcx, reported)
@@ -136,7 +136,7 @@ pub(super) fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: Local
         }
         let reported = tcx.dcx().emit_err(UnconstrainedOpaqueType {
             span: tcx.def_span(def_id),
-            name: tcx.item_name(parent_def_id.to_def_id()),
+            name: tcx.item_ident(parent_def_id.to_def_id()),
             what: match tcx.hir_node(scope) {
                 _ if scope == hir::CRATE_HIR_ID => "module",
                 Node::Item(hir::Item { kind: hir::ItemKind::Mod(_), .. }) => "module",

Diff for: compiler/rustc_hir_analysis/src/errors.rs

@@ -217,7 +217,7 @@ pub(crate) struct DropImplOnWrongItem {
 pub(crate) enum FieldAlreadyDeclared {
     #[diag(hir_analysis_field_already_declared, code = E0124)]
     NotNested {
-        field_name: Symbol,
+        field_name: Ident,
         #[primary_span]
         #[label]
         span: Span,
@@ -226,7 +226,7 @@ pub(crate) enum FieldAlreadyDeclared {
     },
     #[diag(hir_analysis_field_already_declared_current_nested)]
     CurrentNested {
-        field_name: Symbol,
+        field_name: Ident,
         #[primary_span]
         #[label]
         span: Span,
@@ -239,7 +239,7 @@ pub(crate) enum FieldAlreadyDeclared {
     },
     #[diag(hir_analysis_field_already_declared_previous_nested)]
     PreviousNested {
-        field_name: Symbol,
+        field_name: Ident,
         #[primary_span]
         #[label]
         span: Span,
@@ -252,7 +252,7 @@ pub(crate) enum FieldAlreadyDeclared {
     },
     #[diag(hir_analysis_field_already_declared_both_nested)]
     BothNested {
-        field_name: Symbol,
+        field_name: Ident,
         #[primary_span]
         #[label]
         span: Span,
@@ -418,7 +418,7 @@ pub(crate) struct ValueOfAssociatedStructAlreadySpecified {
 pub(crate) struct UnconstrainedOpaqueType {
     #[primary_span]
     pub span: Span,
-    pub name: Symbol,
+    pub name: Ident,
     pub what: &'static str,
 }
 
@@ -802,7 +802,7 @@ pub(crate) struct EnumDiscriminantOverflowed {
     #[label]
     pub span: Span,
     pub discr: String,
-    pub item_name: Symbol,
+    pub item_name: Ident,
     pub wrapped_discr: String,
 }
 
@@ -893,15 +893,15 @@ pub(crate) enum ImplNotMarkedDefault {
         span: Span,
         #[label(hir_analysis_ok_label)]
         ok_label: Span,
-        ident: Symbol,
+        ident: Ident,
     },
     #[diag(hir_analysis_impl_not_marked_default_err, code = E0520)]
     #[note]
     Err {
         #[primary_span]
         span: Span,
         cname: Symbol,
-        ident: Symbol,
+        ident: Ident,
     },
 }
 
@@ -977,7 +977,7 @@ pub(crate) struct MissingTraitItemUnstable {
     pub some_note: bool,
     #[note(hir_analysis_none_note)]
     pub none_note: bool,
-    pub missing_item_name: Symbol,
+    pub missing_item_name: Ident,
     pub feature: Symbol,
     pub reason: String,
 }
@@ -1249,7 +1249,7 @@ pub(crate) struct InherentNominal {
 pub(crate) struct DispatchFromDynZST<'a> {
     #[primary_span]
     pub span: Span,
-    pub name: Symbol,
+    pub name: Ident,
     pub ty: Ty<'a>,
 }
 
@@ -1389,7 +1389,7 @@ pub(crate) struct TyParamFirstLocal<'tcx> {
     pub span: Span,
     #[note(hir_analysis_case_note)]
     pub note: (),
-    pub param: Symbol,
+    pub param: Ident,
     pub local_type: Ty<'tcx>,
 }
 
@@ -1401,7 +1401,7 @@ pub(crate) struct TyParamFirstLocalLint<'tcx> {
     pub span: Span,
     #[note(hir_analysis_case_note)]
     pub note: (),
-    pub param: Symbol,
+    pub param: Ident,
     pub local_type: Ty<'tcx>,
 }
 
@@ -1414,7 +1414,7 @@ pub(crate) struct TyParamSome {
     pub span: Span,
     #[note(hir_analysis_only_note)]
     pub note: (),
-    pub param: Symbol,
+    pub param: Ident,
 }
 
 #[derive(LintDiagnostic)]
@@ -1425,7 +1425,7 @@ pub(crate) struct TyParamSomeLint {
     pub span: Span,
     #[note(hir_analysis_only_note)]
     pub note: (),
-    pub param: Symbol,
+    pub param: Ident,
 }
 
 #[derive(Diagnostic)]
@@ -1533,7 +1533,7 @@ pub(crate) struct UnsupportedDelegation<'a> {
 pub(crate) struct MethodShouldReturnFuture {
     #[primary_span]
     pub span: Span,
-    pub method_name: Symbol,
+    pub method_name: Ident,
     #[note]
     pub trait_item_span: Option<Span>,
 }
@@ -1585,7 +1585,7 @@ pub(crate) struct UnconstrainedGenericParameter {
     #[primary_span]
     #[label]
     pub span: Span,
-    pub param_name: Symbol,
+    pub param_name: Ident,
     pub param_def_kind: &'static str,
     #[note(hir_analysis_const_param_note)]
     pub const_param_note: bool,

Diff for: compiler/rustc_hir_analysis/src/errors/wrong_number_of_generic_args.rs

@@ -495,7 +495,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
                         .iter()
                         .any(|constraint| constraint.ident.name == item.name)
                 })
-                .map(|item| item.name.to_ident_string())
+                .map(|item| self.tcx.item_ident(item.def_id).to_string())
                 .collect()
         } else {
             Vec::default()