diff options
Diffstat (limited to '')
| -rw-r--r-- | compiler/rustc_mir_transform/src/check_unsafety.rs | 115 |
1 files changed, 27 insertions, 88 deletions
diff --git a/compiler/rustc_mir_transform/src/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs index d564f4801..f8f04214a 100644 --- a/compiler/rustc_mir_transform/src/check_unsafety.rs +++ b/compiler/rustc_mir_transform/src/check_unsafety.rs @@ -1,17 +1,16 @@ -use rustc_data_structures::fx::FxHashMap; +use rustc_data_structures::fx::FxHashSet; use rustc_errors::struct_span_err; use rustc_hir as hir; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::hir_id::HirId; use rustc_hir::intravisit; use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor}; +use rustc_middle::mir::*; use rustc_middle::ty::query::Providers; use rustc_middle::ty::{self, TyCtxt}; -use rustc_middle::{lint, mir::*}; use rustc_session::lint::builtin::{UNSAFE_OP_IN_UNSAFE_FN, UNUSED_UNSAFE}; use rustc_session::lint::Level; -use std::collections::hash_map; use std::ops::Bound; pub struct UnsafetyChecker<'a, 'tcx> { @@ -23,10 +22,7 @@ pub struct UnsafetyChecker<'a, 'tcx> { param_env: ty::ParamEnv<'tcx>, /// Used `unsafe` blocks in this function. This is used for the "unused_unsafe" lint. - /// - /// The keys are the used `unsafe` blocks, the UnusedUnsafeKind indicates whether - /// or not any of the usages happen at a place that doesn't allow `unsafe_op_in_unsafe_fn`. - used_unsafe_blocks: FxHashMap<HirId, UsedUnsafeBlockData>, + used_unsafe_blocks: FxHashSet<HirId>, } impl<'a, 'tcx> UnsafetyChecker<'a, 'tcx> { @@ -109,7 +105,8 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> { // safe (at least as emitted during MIR construction) } - StatementKind::CopyNonOverlapping(..) => unreachable!(), + // Move to above list once mir construction uses it. + StatementKind::Intrinsic(..) => unreachable!(), } self.super_statement(statement, location); } @@ -130,10 +127,7 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> { &AggregateKind::Closure(def_id, _) | &AggregateKind::Generator(def_id, _, _) => { let UnsafetyCheckResult { violations, used_unsafe_blocks, .. } = self.tcx.unsafety_check_result(def_id); - self.register_violations( - violations, - used_unsafe_blocks.iter().map(|(&h, &d)| (h, d)), - ); + self.register_violations(violations, used_unsafe_blocks.iter().copied()); } }, _ => {} @@ -257,22 +251,8 @@ impl<'tcx> UnsafetyChecker<'_, 'tcx> { fn register_violations<'a>( &mut self, violations: impl IntoIterator<Item = &'a UnsafetyViolation>, - new_used_unsafe_blocks: impl IntoIterator<Item = (HirId, UsedUnsafeBlockData)>, + new_used_unsafe_blocks: impl IntoIterator<Item = HirId>, ) { - use UsedUnsafeBlockData::{AllAllowedInUnsafeFn, SomeDisallowedInUnsafeFn}; - - let update_entry = |this: &mut Self, hir_id, new_usage| { - match this.used_unsafe_blocks.entry(hir_id) { - hash_map::Entry::Occupied(mut entry) => { - if new_usage == SomeDisallowedInUnsafeFn { - *entry.get_mut() = SomeDisallowedInUnsafeFn; - } - } - hash_map::Entry::Vacant(entry) => { - entry.insert(new_usage); - } - }; - }; let safety = self.body.source_scopes[self.source_info.scope] .local_data .as_ref() @@ -299,22 +279,14 @@ impl<'tcx> UnsafetyChecker<'_, 'tcx> { } }), Safety::BuiltinUnsafe => {} - Safety::ExplicitUnsafe(hir_id) => violations.into_iter().for_each(|violation| { - update_entry( - self, - hir_id, - match self.tcx.lint_level_at_node(UNSAFE_OP_IN_UNSAFE_FN, violation.lint_root).0 - { - Level::Allow => AllAllowedInUnsafeFn(violation.lint_root), - _ => SomeDisallowedInUnsafeFn, - }, - ) + Safety::ExplicitUnsafe(hir_id) => violations.into_iter().for_each(|_violation| { + self.used_unsafe_blocks.insert(hir_id); }), }; - new_used_unsafe_blocks - .into_iter() - .for_each(|(hir_id, usage_data)| update_entry(self, hir_id, usage_data)); + new_used_unsafe_blocks.into_iter().for_each(|hir_id| { + self.used_unsafe_blocks.insert(hir_id); + }); } fn check_mut_borrowing_layout_constrained_field( &mut self, @@ -340,7 +312,7 @@ impl<'tcx> UnsafetyChecker<'_, 'tcx> { } else if !place .ty(self.body, self.tcx) .ty - .is_freeze(self.tcx.at(self.source_info.span), self.param_env) + .is_freeze(self.tcx, self.param_env) { UnsafetyViolationDetails::BorrowOfLayoutConstrainedField } else { @@ -411,34 +383,28 @@ enum Context { struct UnusedUnsafeVisitor<'a, 'tcx> { tcx: TyCtxt<'tcx>, - used_unsafe_blocks: &'a FxHashMap<HirId, UsedUnsafeBlockData>, + used_unsafe_blocks: &'a FxHashSet<HirId>, context: Context, unused_unsafes: &'a mut Vec<(HirId, UnusedUnsafe)>, } impl<'tcx> intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'_, 'tcx> { fn visit_block(&mut self, block: &'tcx hir::Block<'tcx>) { - use UsedUnsafeBlockData::{AllAllowedInUnsafeFn, SomeDisallowedInUnsafeFn}; - if let hir::BlockCheckMode::UnsafeBlock(hir::UnsafeSource::UserProvided) = block.rules { let used = match self.tcx.lint_level_at_node(UNUSED_UNSAFE, block.hir_id) { - (Level::Allow, _) => Some(SomeDisallowedInUnsafeFn), - _ => self.used_unsafe_blocks.get(&block.hir_id).copied(), + (Level::Allow, _) => true, + _ => self.used_unsafe_blocks.contains(&block.hir_id), }; let unused_unsafe = match (self.context, used) { - (_, None) => UnusedUnsafe::Unused, - (Context::Safe, Some(_)) - | (Context::UnsafeFn(_), Some(SomeDisallowedInUnsafeFn)) => { + (_, false) => UnusedUnsafe::Unused, + (Context::Safe, true) | (Context::UnsafeFn(_), true) => { let previous_context = self.context; self.context = Context::UnsafeBlock(block.hir_id); intravisit::walk_block(self, block); self.context = previous_context; return; } - (Context::UnsafeFn(hir_id), Some(AllAllowedInUnsafeFn(lint_root))) => { - UnusedUnsafe::InUnsafeFn(hir_id, lint_root) - } - (Context::UnsafeBlock(hir_id), Some(_)) => UnusedUnsafe::InUnsafeBlock(hir_id), + (Context::UnsafeBlock(hir_id), true) => UnusedUnsafe::InUnsafeBlock(hir_id), }; self.unused_unsafes.push((block.hir_id, unused_unsafe)); } @@ -462,7 +428,7 @@ impl<'tcx> intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'_, 'tcx> { fn check_unused_unsafe( tcx: TyCtxt<'_>, def_id: LocalDefId, - used_unsafe_blocks: &FxHashMap<HirId, UsedUnsafeBlockData>, + used_unsafe_blocks: &FxHashSet<HirId>, ) -> Vec<(HirId, UnusedUnsafe)> { let body_id = tcx.hir().maybe_body_owned_by(def_id); @@ -523,40 +489,20 @@ fn unsafety_check_result<'tcx>( fn report_unused_unsafe(tcx: TyCtxt<'_>, kind: UnusedUnsafe, id: HirId) { let span = tcx.sess.source_map().guess_head_span(tcx.hir().span(id)); - tcx.struct_span_lint_hir(UNUSED_UNSAFE, id, span, |lint| { - let msg = "unnecessary `unsafe` block"; - let mut db = lint.build(msg); - db.span_label(span, msg); + let msg = "unnecessary `unsafe` block"; + tcx.struct_span_lint_hir(UNUSED_UNSAFE, id, span, msg, |lint| { + lint.span_label(span, msg); match kind { UnusedUnsafe::Unused => {} UnusedUnsafe::InUnsafeBlock(id) => { - db.span_label( + lint.span_label( tcx.sess.source_map().guess_head_span(tcx.hir().span(id)), "because it's nested under this `unsafe` block", ); } - UnusedUnsafe::InUnsafeFn(id, usage_lint_root) => { - db.span_label( - tcx.sess.source_map().guess_head_span(tcx.hir().span(id)), - "because it's nested under this `unsafe` fn", - ) - .note( - "this `unsafe` block does contain unsafe operations, \ - but those are already allowed in an `unsafe fn`", - ); - let (level, source) = - tcx.lint_level_at_node(UNSAFE_OP_IN_UNSAFE_FN, usage_lint_root); - assert_eq!(level, Level::Allow); - lint::explain_lint_level_source( - UNSAFE_OP_IN_UNSAFE_FN, - Level::Allow, - source, - &mut db, - ); - } } - db.emit(); + lint }); } @@ -596,15 +542,8 @@ pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: LocalDefId) { UNSAFE_OP_IN_UNSAFE_FN, lint_root, source_info.span, - |lint| { - lint.build(&format!( - "{} is unsafe and requires unsafe block (error E0133)", - description, - )) - .span_label(source_info.span, description) - .note(note) - .emit(); - }, + format!("{} is unsafe and requires unsafe block (error E0133)", description,), + |lint| lint.span_label(source_info.span, description).note(note), ), } } |