diff options
Diffstat (limited to '')
| -rw-r--r-- | compiler/rustc_passes/src/dead.rs | 158 |
1 files changed, 70 insertions, 88 deletions
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs index 1e2fbeb38..753d01f46 100644 --- a/compiler/rustc_passes/src/dead.rs +++ b/compiler/rustc_passes/src/dead.rs @@ -11,13 +11,15 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::intravisit::{self, Visitor}; use rustc_hir::{Node, PatKind, TyKind}; use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags; -use rustc_middle::middle::privacy; +use rustc_middle::middle::privacy::Level; use rustc_middle::ty::query::Providers; use rustc_middle::ty::{self, DefIdTree, TyCtxt}; use rustc_session::lint; use rustc_span::symbol::{sym, Symbol}; use std::mem; +use crate::errors::UselessAssignment; + // Any local node that may call something in its body block should be // explored. For example, if it's a live Node::Item that is a // function, then we should explore its block to check for codes that @@ -102,14 +104,8 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { } } Res::Def(_, def_id) => self.check_def_id(def_id), - Res::SelfTy { trait_: t, alias_to: i } => { - if let Some(t) = t { - self.check_def_id(t); - } - if let Some((i, _)) = i { - self.check_def_id(i); - } - } + Res::SelfTyParam { trait_: t } => self.check_def_id(t), + Res::SelfTyAlias { alias_to: i, .. } => self.check_def_id(i), Res::ToolMod | Res::NonMacroAttr(..) | Res::Err => {} } } @@ -186,18 +182,11 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { && !assign.span.from_expansion() { let is_field_assign = matches!(lhs.kind, hir::ExprKind::Field(..)); - self.tcx.struct_span_lint_hir( + self.tcx.emit_spanned_lint( lint::builtin::DEAD_CODE, assign.hir_id, assign.span, - |lint| { - lint.build(&format!( - "useless assignment of {} of type `{}` to itself", - if is_field_assign { "field" } else { "variable" }, - self.typeck_results().expr_ty(lhs), - )) - .emit(); - }, + UselessAssignment { is_field_assign, ty: self.typeck_results().expr_ty(lhs) } ) } } @@ -226,19 +215,16 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { lhs: &hir::Pat<'_>, res: Res, pats: &[hir::Pat<'_>], - dotdot: Option<usize>, + dotdot: hir::DotDotPos, ) { let variant = match self.typeck_results().node_type(lhs.hir_id).kind() { ty::Adt(adt, _) => adt.variant_of_res(res), _ => span_bug!(lhs.span, "non-ADT in tuple struct pattern"), }; - let first_n = pats.iter().enumerate().take(dotdot.unwrap_or(pats.len())); + let dotdot = dotdot.as_opt_usize().unwrap_or(pats.len()); + let first_n = pats.iter().enumerate().take(dotdot); let missing = variant.fields.len() - pats.len(); - let last_n = pats - .iter() - .enumerate() - .skip(dotdot.unwrap_or(pats.len())) - .map(|(idx, pat)| (idx + missing, pat)); + let last_n = pats.iter().enumerate().skip(dotdot).map(|(idx, pat)| (idx + missing, pat)); for (idx, pat) in first_n.chain(last_n) { if let PatKind::Wild = pat.kind { continue; @@ -294,8 +280,8 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { } fn visit_node(&mut self, node: Node<'tcx>) { - if let Node::ImplItem(hir::ImplItem { def_id, .. }) = node - && self.should_ignore_item(def_id.to_def_id()) + if let Node::ImplItem(hir::ImplItem { owner_id, .. }) = node + && self.should_ignore_item(owner_id.to_def_id()) { return; } @@ -307,7 +293,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { match node { Node::Item(item) => match item.kind { hir::ItemKind::Struct(..) | hir::ItemKind::Union(..) => { - let def = self.tcx.adt_def(item.def_id); + let def = self.tcx.adt_def(item.owner_id); self.repr_has_repr_c = def.repr().c(); self.repr_has_repr_simd = def.repr().simd(); @@ -320,7 +306,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { intravisit::walk_trait_item(self, trait_item); } Node::ImplItem(impl_item) => { - let item = self.tcx.local_parent(impl_item.def_id); + let item = self.tcx.local_parent(impl_item.owner_id.def_id); if self.tcx.impl_trait_ref(item).is_none() { //// If it's a type whose items are live, then it's live, too. //// This is done to handle the case where, for example, the static @@ -368,14 +354,7 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> { self.maybe_typeck_results = old_maybe_typeck_results; } - fn visit_variant_data( - &mut self, - def: &'tcx hir::VariantData<'tcx>, - _: Symbol, - _: &hir::Generics<'_>, - _: hir::HirId, - _: rustc_span::Span, - ) { + fn visit_variant_data(&mut self, def: &'tcx hir::VariantData<'tcx>) { let tcx = self.tcx; let has_repr_c = self.repr_has_repr_c; let has_repr_simd = self.repr_has_repr_simd; @@ -384,7 +363,7 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> { if has_repr_c || (f.is_positional() && has_repr_simd) { return Some(def_id); } - if !tcx.visibility(f.hir_id.owner).is_public() { + if !tcx.visibility(f.hir_id.owner.def_id).is_public() { return None; } if tcx.visibility(def_id).is_public() { Some(def_id) } else { None } @@ -457,7 +436,7 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> { } fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) { - if let TyKind::OpaqueDef(item_id, _) = ty.kind { + if let TyKind::OpaqueDef(item_id, _, _) = ty.kind { let item = self.tcx.hir().item(item_id); intravisit::walk_item(self, item); } @@ -538,10 +517,10 @@ fn check_item<'tcx>( ) { let allow_dead_code = has_allow_dead_code_or_lang_attr(tcx, id.hir_id()); if allow_dead_code { - worklist.push(id.def_id); + worklist.push(id.owner_id.def_id); } - match tcx.def_kind(id.def_id) { + match tcx.def_kind(id.owner_id) { DefKind::Enum => { let item = tcx.hir().item(id); if let hir::ItemKind::Enum(ref enum_def, _) = item.kind { @@ -561,15 +540,15 @@ fn check_item<'tcx>( } } DefKind::Impl => { - let of_trait = tcx.impl_trait_ref(id.def_id); + let of_trait = tcx.impl_trait_ref(id.owner_id); if of_trait.is_some() { - worklist.push(id.def_id); + worklist.push(id.owner_id.def_id); } // get DefIds from another query let local_def_ids = tcx - .associated_item_def_ids(id.def_id) + .associated_item_def_ids(id.owner_id) .iter() .filter_map(|def_id| def_id.as_local()); @@ -587,12 +566,12 @@ fn check_item<'tcx>( if let hir::ItemKind::Struct(ref variant_data, _) = item.kind && let Some(ctor_hir_id) = variant_data.ctor_hir_id() { - struct_constructors.insert(tcx.hir().local_def_id(ctor_hir_id), item.def_id); + struct_constructors.insert(tcx.hir().local_def_id(ctor_hir_id), item.owner_id.def_id); } } DefKind::GlobalAsm => { // global_asm! is always live. - worklist.push(id.def_id); + worklist.push(id.owner_id.def_id); } _ => {} } @@ -600,12 +579,12 @@ fn check_item<'tcx>( fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, worklist: &mut Vec<LocalDefId>, id: hir::TraitItemId) { use hir::TraitItemKind::{Const, Fn}; - if matches!(tcx.def_kind(id.def_id), DefKind::AssocConst | DefKind::AssocFn) { + if matches!(tcx.def_kind(id.owner_id), DefKind::AssocConst | DefKind::AssocFn) { let trait_item = tcx.hir().trait_item(id); if matches!(trait_item.kind, Const(_, Some(_)) | Fn(_, hir::TraitFn::Provided(_))) && has_allow_dead_code_or_lang_attr(tcx, trait_item.hir_id()) { - worklist.push(trait_item.def_id); + worklist.push(trait_item.owner_id.def_id); } } } @@ -615,27 +594,24 @@ fn check_foreign_item<'tcx>( worklist: &mut Vec<LocalDefId>, id: hir::ForeignItemId, ) { - if matches!(tcx.def_kind(id.def_id), DefKind::Static(_) | DefKind::Fn) + if matches!(tcx.def_kind(id.owner_id), DefKind::Static(_) | DefKind::Fn) && has_allow_dead_code_or_lang_attr(tcx, id.hir_id()) { - worklist.push(id.def_id); + worklist.push(id.owner_id.def_id); } } fn create_and_seed_worklist<'tcx>( tcx: TyCtxt<'tcx>, ) -> (Vec<LocalDefId>, FxHashMap<LocalDefId, LocalDefId>) { - let access_levels = &tcx.privacy_access_levels(()); + let effective_visibilities = &tcx.effective_visibilities(()); // see `MarkSymbolVisitor::struct_constructors` let mut struct_constructors = Default::default(); - let mut worklist = access_levels - .map + let mut worklist = effective_visibilities .iter() - .filter_map( - |(&id, &level)| { - if level >= privacy::AccessLevel::Reachable { Some(id) } else { None } - }, - ) + .filter_map(|(&id, effective_vis)| { + effective_vis.is_public_at_level(Level::Reachable).then_some(id) + }) // Seed entry point .chain(tcx.entry_fn(()).and_then(|(def_id, _)| def_id.as_local())) .collect::<Vec<_>>(); @@ -736,6 +712,26 @@ impl<'tcx> DeadVisitor<'tcx> { }) .collect(); + let descr = tcx.def_kind(first_id).descr(first_id.to_def_id()); + let span_len = dead_codes.len(); + let names = match &names[..] { + _ if span_len > 6 => String::new(), + [name] => format!("`{name}` "), + [names @ .., last] => { + format!( + "{} and `{last}` ", + names.iter().map(|name| format!("`{name}`")).join(", ") + ) + } + [] => unreachable!(), + }; + let msg = format!( + "{these}{descr}{s} {names}{are} never {participle}", + these = if span_len > 6 { "multiple " } else { "" }, + s = pluralize!(span_len), + are = pluralize!("is", span_len), + ); + tcx.struct_span_lint_hir( if is_positional { lint::builtin::UNUSED_TUPLE_STRUCT_FIELDS @@ -744,27 +740,8 @@ impl<'tcx> DeadVisitor<'tcx> { }, tcx.hir().local_def_id_to_hir_id(first_id), MultiSpan::from_spans(spans.clone()), - |lint| { - let descr = tcx.def_kind(first_id).descr(first_id.to_def_id()); - let span_len = dead_codes.len(); - let names = match &names[..] { - _ if span_len > 6 => String::new(), - [name] => format!("`{name}` "), - [names @ .., last] => { - format!( - "{} and `{last}` ", - names.iter().map(|name| format!("`{name}`")).join(", ") - ) - } - [] => unreachable!(), - }; - let mut err = lint.build(&format!( - "{these}{descr}{s} {names}{are} never {participle}", - these = if span_len > 6 { "multiple " } else { "" }, - s = pluralize!(span_len), - are = pluralize!("is", span_len), - )); - + msg, + |err| { if is_positional { err.multipart_suggestion( &format!( @@ -810,7 +787,7 @@ impl<'tcx> DeadVisitor<'tcx> { ); err.note(&msg); } - err.emit(); + err }, ); } @@ -884,19 +861,19 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) { let module_items = tcx.hir_module_items(module); for item in module_items.items() { - if !live_symbols.contains(&item.def_id) { - let parent = tcx.local_parent(item.def_id); + if !live_symbols.contains(&item.owner_id.def_id) { + let parent = tcx.local_parent(item.owner_id.def_id); if parent != module && !live_symbols.contains(&parent) { // We already have diagnosed something. continue; } - visitor.check_definition(item.def_id); + visitor.check_definition(item.owner_id.def_id); continue; } - let def_kind = tcx.def_kind(item.def_id); + let def_kind = tcx.def_kind(item.owner_id); if let DefKind::Struct | DefKind::Union | DefKind::Enum = def_kind { - let adt = tcx.adt_def(item.def_id); + let adt = tcx.adt_def(item.owner_id); let mut dead_variants = Vec::new(); for variant in adt.variants() { @@ -939,16 +916,21 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) { visitor.warn_dead_fields_and_variants(def_id, "read", dead_fields, is_positional) } - visitor.warn_dead_fields_and_variants(item.def_id, "constructed", dead_variants, false); + visitor.warn_dead_fields_and_variants( + item.owner_id.def_id, + "constructed", + dead_variants, + false, + ); } } for impl_item in module_items.impl_items() { - visitor.check_definition(impl_item.def_id); + visitor.check_definition(impl_item.owner_id.def_id); } for foreign_item in module_items.foreign_items() { - visitor.check_definition(foreign_item.def_id); + visitor.check_definition(foreign_item.owner_id.def_id); } // We do not warn trait items. |