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-rw-r--r--compiler/rustc_passes/src/dead.rs200
1 files changed, 92 insertions, 108 deletions
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index 753d01f46..a71ae717a 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -4,7 +4,7 @@
use itertools::Itertools;
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_errors::{pluralize, Applicability, MultiSpan};
+use rustc_errors::MultiSpan;
use rustc_hir as hir;
use rustc_hir::def::{CtorOf, DefKind, Res};
use rustc_hir::def_id::{DefId, LocalDefId};
@@ -18,7 +18,10 @@ use rustc_session::lint;
use rustc_span::symbol::{sym, Symbol};
use std::mem;
-use crate::errors::UselessAssignment;
+use crate::errors::{
+ ChangeFieldsToBeOfUnitType, IgnoredDerivedImpls, MultipleDeadCodes, ParentInfo,
+ 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
@@ -121,7 +124,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
fn handle_field_access(&mut self, lhs: &hir::Expr<'_>, hir_id: hir::HirId) {
match self.typeck_results().expr_ty_adjusted(lhs).kind() {
ty::Adt(def, _) => {
- let index = self.tcx.field_index(hir_id, self.typeck_results());
+ let index = self.typeck_results().field_index(hir_id);
self.insert_def_id(def.non_enum_variant().fields[index].did);
}
ty::Tuple(..) => {}
@@ -205,7 +208,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
if let PatKind::Wild = pat.pat.kind {
continue;
}
- let index = self.tcx.field_index(pat.hir_id, self.typeck_results());
+ let index = self.typeck_results().field_index(pat.hir_id);
self.insert_def_id(variant.fields[index].did);
}
}
@@ -338,7 +341,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
fn mark_as_used_if_union(&mut self, adt: ty::AdtDef<'tcx>, fields: &[hir::ExprField<'_>]) {
if adt.is_union() && adt.non_enum_variant().fields.len() > 1 && adt.did().is_local() {
for field in fields {
- let index = self.tcx.field_index(field.hir_id, self.typeck_results());
+ let index = self.typeck_results().field_index(field.hir_id);
self.insert_def_id(adt.non_enum_variant().fields[index].did);
}
}
@@ -359,7 +362,7 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> {
let has_repr_c = self.repr_has_repr_c;
let has_repr_simd = self.repr_has_repr_simd;
let live_fields = def.fields().iter().filter_map(|f| {
- let def_id = tcx.hir().local_def_id(f.hir_id);
+ let def_id = f.def_id;
if has_repr_c || (f.is_positional() && has_repr_simd) {
return Some(def_id);
}
@@ -430,7 +433,7 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> {
self.in_pat = false;
}
- fn visit_path(&mut self, path: &'tcx hir::Path<'tcx>, _: hir::HirId) {
+ fn visit_path(&mut self, path: &hir::Path<'tcx>, _: hir::HirId) {
self.handle_res(path.res);
intravisit::walk_path(self, path);
}
@@ -470,11 +473,6 @@ fn has_allow_dead_code_or_lang_attr_helper(
return true;
}
- // (To be) stable attribute for #[lang = "oom"]
- if tcx.sess.contains_name(attrs, sym::alloc_error_handler) {
- return true;
- }
-
let def_id = tcx.hir().local_def_id(id);
if tcx.def_kind(def_id).has_codegen_attrs() {
let cg_attrs = tcx.codegen_fn_attrs(def_id);
@@ -524,17 +522,13 @@ fn check_item<'tcx>(
DefKind::Enum => {
let item = tcx.hir().item(id);
if let hir::ItemKind::Enum(ref enum_def, _) = item.kind {
- let hir = tcx.hir();
if allow_dead_code {
- worklist.extend(
- enum_def.variants.iter().map(|variant| hir.local_def_id(variant.id)),
- );
+ worklist.extend(enum_def.variants.iter().map(|variant| variant.def_id));
}
for variant in enum_def.variants {
- if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
- struct_constructors
- .insert(hir.local_def_id(ctor_hir_id), hir.local_def_id(variant.id));
+ if let Some(ctor_def_id) = variant.data.ctor_def_id() {
+ struct_constructors.insert(ctor_def_id, variant.def_id);
}
}
}
@@ -698,99 +692,89 @@ impl<'tcx> DeadVisitor<'tcx> {
parent_item: Option<LocalDefId>,
is_positional: bool,
) {
- if let Some(&first_id) = dead_codes.first() {
- let tcx = self.tcx;
- let names: Vec<_> = dead_codes
- .iter()
- .map(|&def_id| tcx.item_name(def_id.to_def_id()).to_string())
- .collect();
- let spans: Vec<_> = dead_codes
- .iter()
- .map(|&def_id| match tcx.def_ident_span(def_id) {
- Some(s) => s.with_ctxt(tcx.def_span(def_id).ctxt()),
- None => tcx.def_span(def_id),
+ let Some(&first_id) = dead_codes.first() else {
+ return;
+ };
+ let tcx = self.tcx;
+ let names: Vec<_> =
+ dead_codes.iter().map(|&def_id| tcx.item_name(def_id.to_def_id())).collect();
+ let spans: Vec<_> = dead_codes
+ .iter()
+ .map(|&def_id| match tcx.def_ident_span(def_id) {
+ Some(s) => s.with_ctxt(tcx.def_span(def_id).ctxt()),
+ None => tcx.def_span(def_id),
+ })
+ .collect();
+
+ let descr = tcx.def_kind(first_id).descr(first_id.to_def_id());
+ let num = dead_codes.len();
+ let multiple = num > 6;
+ let name_list = names.into();
+
+ let lint = if is_positional {
+ lint::builtin::UNUSED_TUPLE_STRUCT_FIELDS
+ } else {
+ lint::builtin::DEAD_CODE
+ };
+
+ let parent_info = if let Some(parent_item) = parent_item {
+ let parent_descr = tcx.def_kind(parent_item).descr(parent_item.to_def_id());
+ Some(ParentInfo {
+ num,
+ descr,
+ parent_descr,
+ span: tcx.def_ident_span(parent_item).unwrap(),
+ })
+ } else {
+ None
+ };
+
+ let encl_def_id = parent_item.unwrap_or(first_id);
+ let ignored_derived_impls =
+ if let Some(ign_traits) = self.ignored_derived_traits.get(&encl_def_id) {
+ let trait_list = ign_traits
+ .iter()
+ .map(|(trait_id, _)| self.tcx.item_name(*trait_id))
+ .collect::<Vec<_>>();
+ let trait_list_len = trait_list.len();
+ Some(IgnoredDerivedImpls {
+ name: self.tcx.item_name(encl_def_id.to_def_id()),
+ trait_list: trait_list.into(),
+ trait_list_len,
})
- .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!(),
+ } else {
+ None
};
- 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
- } else {
- lint::builtin::DEAD_CODE
- },
- tcx.hir().local_def_id_to_hir_id(first_id),
- MultiSpan::from_spans(spans.clone()),
- msg,
- |err| {
- if is_positional {
- err.multipart_suggestion(
- &format!(
- "consider changing the field{s} to be of unit type to \
- suppress this warning while preserving the field \
- numbering, or remove the field{s}",
- s = pluralize!(span_len)
- ),
- spans.iter().map(|sp| (*sp, "()".to_string())).collect(),
- // "HasPlaceholders" because applying this fix by itself isn't
- // enough: All constructor calls have to be adjusted as well
- Applicability::HasPlaceholders,
- );
- }
- if let Some(parent_item) = parent_item {
- let parent_descr = tcx.def_kind(parent_item).descr(parent_item.to_def_id());
- err.span_label(
- tcx.def_ident_span(parent_item).unwrap(),
- format!("{descr}{s} in this {parent_descr}", s = pluralize!(span_len)),
- );
- }
+ let diag = if is_positional {
+ MultipleDeadCodes::UnusedTupleStructFields {
+ multiple,
+ num,
+ descr,
+ participle,
+ name_list,
+ change_fields_suggestion: ChangeFieldsToBeOfUnitType { num, spans: spans.clone() },
+ parent_info,
+ ignored_derived_impls,
+ }
+ } else {
+ MultipleDeadCodes::DeadCodes {
+ multiple,
+ num,
+ descr,
+ participle,
+ name_list,
+ parent_info,
+ ignored_derived_impls,
+ }
+ };
- let encl_def_id = parent_item.unwrap_or(first_id);
- if let Some(ign_traits) = self.ignored_derived_traits.get(&encl_def_id) {
- let traits_str = ign_traits
- .iter()
- .map(|(trait_id, _)| format!("`{}`", self.tcx.item_name(*trait_id)))
- .collect::<Vec<_>>()
- .join(" and ");
- let plural_s = pluralize!(ign_traits.len());
- let article = if ign_traits.len() > 1 { "" } else { "a " };
- let is_are = if ign_traits.len() > 1 { "these are" } else { "this is" };
- let msg = format!(
- "`{}` has {}derived impl{} for the trait{} {}, but {} \
- intentionally ignored during dead code analysis",
- self.tcx.item_name(encl_def_id.to_def_id()),
- article,
- plural_s,
- plural_s,
- traits_str,
- is_are
- );
- err.note(&msg);
- }
- err
- },
- );
- }
+ self.tcx.emit_spanned_lint(
+ lint,
+ tcx.hir().local_def_id_to_hir_id(first_id),
+ MultiSpan::from_spans(spans),
+ diag,
+ );
}
fn warn_dead_fields_and_variants(
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-06 05:56:42 +0000