| use rustc_data_structures::fx::FxHashSet; |
| |
| use rustc::ty::query::Providers; |
| use rustc::ty::{self, TyCtxt}; |
| use rustc::ty::cast::CastTy; |
| use rustc::hir; |
| use rustc::hir::Node; |
| use rustc::hir::def_id::DefId; |
| use rustc::lint::builtin::{SAFE_PACKED_BORROWS, UNUSED_UNSAFE}; |
| use rustc::mir::*; |
| use rustc::mir::visit::{PlaceContext, Visitor, MutatingUseContext}; |
| |
| use syntax::symbol::{Symbol, sym}; |
| |
| use std::ops::Bound; |
| |
| use crate::util; |
| |
| use rustc_error_codes::*; |
| |
| pub struct UnsafetyChecker<'a, 'tcx> { |
| body: &'a Body<'tcx>, |
| const_context: bool, |
| min_const_fn: bool, |
| violations: Vec<UnsafetyViolation>, |
| source_info: SourceInfo, |
| tcx: TyCtxt<'tcx>, |
| param_env: ty::ParamEnv<'tcx>, |
| /// Mark an `unsafe` block as used, so we don't lint it. |
| used_unsafe: FxHashSet<hir::HirId>, |
| inherited_blocks: Vec<(hir::HirId, bool)>, |
| } |
| |
| impl<'a, 'tcx> UnsafetyChecker<'a, 'tcx> { |
| fn new( |
| const_context: bool, |
| min_const_fn: bool, |
| body: &'a Body<'tcx>, |
| tcx: TyCtxt<'tcx>, |
| param_env: ty::ParamEnv<'tcx>, |
| ) -> Self { |
| // sanity check |
| if min_const_fn { |
| assert!(const_context); |
| } |
| Self { |
| body, |
| const_context, |
| min_const_fn, |
| violations: vec![], |
| source_info: SourceInfo { |
| span: body.span, |
| scope: OUTERMOST_SOURCE_SCOPE |
| }, |
| tcx, |
| param_env, |
| used_unsafe: Default::default(), |
| inherited_blocks: vec![], |
| } |
| } |
| } |
| |
| impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> { |
| fn visit_terminator(&mut self, |
| terminator: &Terminator<'tcx>, |
| location: Location) |
| { |
| self.source_info = terminator.source_info; |
| match terminator.kind { |
| TerminatorKind::Goto { .. } | |
| TerminatorKind::SwitchInt { .. } | |
| TerminatorKind::Drop { .. } | |
| TerminatorKind::Yield { .. } | |
| TerminatorKind::Assert { .. } | |
| TerminatorKind::DropAndReplace { .. } | |
| TerminatorKind::GeneratorDrop | |
| TerminatorKind::Resume | |
| TerminatorKind::Abort | |
| TerminatorKind::Return | |
| TerminatorKind::Unreachable | |
| TerminatorKind::FalseEdges { .. } | |
| TerminatorKind::FalseUnwind { .. } => { |
| // safe (at least as emitted during MIR construction) |
| } |
| |
| TerminatorKind::Call { ref func, .. } => { |
| let func_ty = func.ty(self.body, self.tcx); |
| let sig = func_ty.fn_sig(self.tcx); |
| if let hir::Unsafety::Unsafe = sig.unsafety() { |
| self.require_unsafe("call to unsafe function", |
| "consult the function's documentation for information on how to avoid \ |
| undefined behavior", UnsafetyViolationKind::GeneralAndConstFn) |
| } |
| } |
| } |
| self.super_terminator(terminator, location); |
| } |
| |
| fn visit_statement(&mut self, |
| statement: &Statement<'tcx>, |
| location: Location) |
| { |
| self.source_info = statement.source_info; |
| match statement.kind { |
| StatementKind::Assign(..) | |
| StatementKind::FakeRead(..) | |
| StatementKind::SetDiscriminant { .. } | |
| StatementKind::StorageLive(..) | |
| StatementKind::StorageDead(..) | |
| StatementKind::Retag { .. } | |
| StatementKind::AscribeUserType(..) | |
| StatementKind::Nop => { |
| // safe (at least as emitted during MIR construction) |
| } |
| |
| StatementKind::InlineAsm { .. } => { |
| self.require_unsafe("use of inline assembly", |
| "inline assembly is entirely unchecked and can cause undefined behavior", |
| UnsafetyViolationKind::General) |
| }, |
| } |
| self.super_statement(statement, location); |
| } |
| |
| fn visit_rvalue(&mut self, |
| rvalue: &Rvalue<'tcx>, |
| location: Location) |
| { |
| match rvalue { |
| Rvalue::Aggregate(box ref aggregate, _) => { |
| match aggregate { |
| &AggregateKind::Array(..) | |
| &AggregateKind::Tuple => {} |
| &AggregateKind::Adt(ref def, ..) => { |
| match self.tcx.layout_scalar_valid_range(def.did) { |
| (Bound::Unbounded, Bound::Unbounded) => {}, |
| _ => self.require_unsafe( |
| "initializing type with `rustc_layout_scalar_valid_range` attr", |
| "initializing a layout restricted type's field with a value \ |
| outside the valid range is undefined behavior", |
| UnsafetyViolationKind::GeneralAndConstFn, |
| ), |
| } |
| } |
| &AggregateKind::Closure(def_id, _) | |
| &AggregateKind::Generator(def_id, _, _) => { |
| let UnsafetyCheckResult { |
| violations, unsafe_blocks |
| } = self.tcx.unsafety_check_result(def_id); |
| self.register_violations(&violations, &unsafe_blocks); |
| } |
| } |
| }, |
| // casting pointers to ints is unsafe in const fn because the const evaluator cannot |
| // possibly know what the result of various operations like `address / 2` would be |
| // pointers during const evaluation have no integral address, only an abstract one |
| Rvalue::Cast(CastKind::Misc, ref operand, cast_ty) |
| if self.const_context && self.tcx.features().const_raw_ptr_to_usize_cast => { |
| let operand_ty = operand.ty(self.body, self.tcx); |
| let cast_in = CastTy::from_ty(operand_ty).expect("bad input type for cast"); |
| let cast_out = CastTy::from_ty(cast_ty).expect("bad output type for cast"); |
| match (cast_in, cast_out) { |
| (CastTy::Ptr(_), CastTy::Int(_)) | |
| (CastTy::FnPtr, CastTy::Int(_)) => { |
| self.register_violations(&[UnsafetyViolation { |
| source_info: self.source_info, |
| description: Symbol::intern("cast of pointer to int"), |
| details: Symbol::intern("casting pointers to integers in constants"), |
| kind: UnsafetyViolationKind::General, |
| }], &[]); |
| }, |
| _ => {}, |
| } |
| } |
| // raw pointer and fn pointer operations are unsafe as it is not clear whether one |
| // pointer would be "less" or "equal" to another, because we cannot know where llvm |
| // or the linker will place various statics in memory. Without this information the |
| // result of a comparison of addresses would differ between runtime and compile-time. |
| Rvalue::BinaryOp(_, ref lhs, _) |
| if self.const_context && self.tcx.features().const_compare_raw_pointers => { |
| if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(self.body, self.tcx).kind { |
| self.register_violations(&[UnsafetyViolation { |
| source_info: self.source_info, |
| description: Symbol::intern("pointer operation"), |
| details: Symbol::intern("operations on pointers in constants"), |
| kind: UnsafetyViolationKind::General, |
| }], &[]); |
| } |
| } |
| _ => {}, |
| } |
| self.super_rvalue(rvalue, location); |
| } |
| |
| fn visit_place(&mut self, |
| place: &Place<'tcx>, |
| context: PlaceContext, |
| _location: Location) { |
| match place.base { |
| PlaceBase::Local(..) => { |
| // Locals are safe. |
| } |
| PlaceBase::Static(box Static { kind: StaticKind::Promoted(_, _), .. }) => { |
| bug!("unsafety checking should happen before promotion"); |
| } |
| PlaceBase::Static(box Static { kind: StaticKind::Static, .. }) => { |
| bug!("StaticKind::Static should not exist"); |
| } |
| } |
| |
| for (i, elem) in place.projection.iter().enumerate() { |
| let proj_base = &place.projection[..i]; |
| |
| if context.is_borrow() { |
| if util::is_disaligned(self.tcx, self.body, self.param_env, place) { |
| let source_info = self.source_info; |
| let lint_root = self.body.source_scopes[source_info.scope] |
| .local_data |
| .as_ref() |
| .assert_crate_local() |
| .lint_root; |
| self.register_violations(&[UnsafetyViolation { |
| source_info, |
| description: Symbol::intern("borrow of packed field"), |
| details: Symbol::intern( |
| "fields of packed structs might be misaligned: dereferencing a \ |
| misaligned pointer or even just creating a misaligned reference \ |
| is undefined behavior"), |
| kind: UnsafetyViolationKind::BorrowPacked(lint_root) |
| }], &[]); |
| } |
| } |
| let is_borrow_of_interior_mut = context.is_borrow() && |
| !Place::ty_from(&place.base, proj_base, self.body, self.tcx) |
| .ty |
| .is_freeze(self.tcx, self.param_env, self.source_info.span); |
| // prevent |
| // * `&mut x.field` |
| // * `x.field = y;` |
| // * `&x.field` if `field`'s type has interior mutability |
| // because either of these would allow modifying the layout constrained field and |
| // insert values that violate the layout constraints. |
| if context.is_mutating_use() || is_borrow_of_interior_mut { |
| self.check_mut_borrowing_layout_constrained_field( |
| place, context.is_mutating_use(), |
| ); |
| } |
| let old_source_info = self.source_info; |
| if let (PlaceBase::Local(local), []) = (&place.base, proj_base) { |
| let decl = &self.body.local_decls[*local]; |
| if decl.internal { |
| // Internal locals are used in the `move_val_init` desugaring. |
| // We want to check unsafety against the source info of the |
| // desugaring, rather than the source info of the RHS. |
| self.source_info = self.body.local_decls[*local].source_info; |
| } else if let LocalInfo::StaticRef { def_id, .. } = decl.local_info { |
| if self.tcx.is_mutable_static(def_id) { |
| self.require_unsafe( |
| "use of mutable static", |
| "mutable statics can be mutated by multiple threads: aliasing \ |
| violations or data races will cause undefined behavior", |
| UnsafetyViolationKind::General, |
| ); |
| return; |
| } else if self.tcx.is_foreign_item(def_id) { |
| self.require_unsafe( |
| "use of extern static", |
| "extern statics are not controlled by the Rust type system: \ |
| invalid data, aliasing violations or data races will cause \ |
| undefined behavior", |
| UnsafetyViolationKind::General, |
| ); |
| return; |
| } |
| } |
| } |
| let base_ty = Place::ty_from(&place.base, proj_base, self.body, self.tcx).ty; |
| match base_ty.kind { |
| ty::RawPtr(..) => { |
| self.require_unsafe("dereference of raw pointer", |
| "raw pointers may be NULL, dangling or unaligned; they can violate \ |
| aliasing rules and cause data races: all of these are undefined \ |
| behavior", UnsafetyViolationKind::General) |
| } |
| ty::Adt(adt, _) => { |
| if adt.is_union() { |
| if context == PlaceContext::MutatingUse(MutatingUseContext::Store) || |
| context == PlaceContext::MutatingUse(MutatingUseContext::Drop) || |
| context == PlaceContext::MutatingUse( |
| MutatingUseContext::AsmOutput |
| ) |
| { |
| let elem_ty = match elem { |
| ProjectionElem::Field(_, ty) => ty, |
| _ => span_bug!( |
| self.source_info.span, |
| "non-field projection {:?} from union?", |
| place) |
| }; |
| if !elem_ty.is_copy_modulo_regions( |
| self.tcx, |
| self.param_env, |
| self.source_info.span, |
| ) { |
| self.require_unsafe( |
| "assignment to non-`Copy` union field", |
| "the previous content of the field will be dropped, which \ |
| causes undefined behavior if the field was not properly \ |
| initialized", UnsafetyViolationKind::GeneralAndConstFn) |
| } else { |
| // write to non-move union, safe |
| } |
| } else { |
| self.require_unsafe("access to union field", |
| "the field may not be properly initialized: using \ |
| uninitialized data will cause undefined behavior", |
| UnsafetyViolationKind::GeneralAndConstFn) |
| } |
| } |
| } |
| _ => {} |
| } |
| self.source_info = old_source_info; |
| } |
| } |
| } |
| |
| impl<'a, 'tcx> UnsafetyChecker<'a, 'tcx> { |
| fn require_unsafe( |
| &mut self, |
| description: &'static str, |
| details: &'static str, |
| kind: UnsafetyViolationKind, |
| ) { |
| let source_info = self.source_info; |
| self.register_violations(&[UnsafetyViolation { |
| source_info, |
| description: Symbol::intern(description), |
| details: Symbol::intern(details), |
| kind, |
| }], &[]); |
| } |
| |
| fn register_violations(&mut self, |
| violations: &[UnsafetyViolation], |
| unsafe_blocks: &[(hir::HirId, bool)]) { |
| let safety = self.body.source_scopes[self.source_info.scope] |
| .local_data |
| .as_ref() |
| .assert_crate_local() |
| .safety; |
| let within_unsafe = match safety { |
| // `unsafe` blocks are required in safe code |
| Safety::Safe => { |
| for violation in violations { |
| let mut violation = violation.clone(); |
| match violation.kind { |
| UnsafetyViolationKind::GeneralAndConstFn | |
| UnsafetyViolationKind::General => {}, |
| UnsafetyViolationKind::BorrowPacked(_) => if self.min_const_fn { |
| // const fns don't need to be backwards compatible and can |
| // emit these violations as a hard error instead of a backwards |
| // compat lint |
| violation.kind = UnsafetyViolationKind::General; |
| }, |
| } |
| if !self.violations.contains(&violation) { |
| self.violations.push(violation) |
| } |
| } |
| false |
| } |
| // `unsafe` function bodies allow unsafe without additional unsafe blocks |
| Safety::BuiltinUnsafe | Safety::FnUnsafe => true, |
| Safety::ExplicitUnsafe(hir_id) => { |
| // mark unsafe block as used if there are any unsafe operations inside |
| if !violations.is_empty() { |
| self.used_unsafe.insert(hir_id); |
| } |
| // only some unsafety is allowed in const fn |
| if self.min_const_fn { |
| for violation in violations { |
| match violation.kind { |
| // these unsafe things are stable in const fn |
| UnsafetyViolationKind::GeneralAndConstFn => {}, |
| // these things are forbidden in const fns |
| UnsafetyViolationKind::General | |
| UnsafetyViolationKind::BorrowPacked(_) => { |
| let mut violation = violation.clone(); |
| // const fns don't need to be backwards compatible and can |
| // emit these violations as a hard error instead of a backwards |
| // compat lint |
| violation.kind = UnsafetyViolationKind::General; |
| if !self.violations.contains(&violation) { |
| self.violations.push(violation) |
| } |
| }, |
| } |
| } |
| } |
| true |
| } |
| }; |
| self.inherited_blocks.extend(unsafe_blocks.iter().map(|&(hir_id, is_used)| { |
| (hir_id, is_used && !within_unsafe) |
| })); |
| } |
| fn check_mut_borrowing_layout_constrained_field( |
| &mut self, |
| place: &Place<'tcx>, |
| is_mut_use: bool, |
| ) { |
| let mut cursor = place.projection.as_ref(); |
| while let &[ref proj_base @ .., elem] = cursor { |
| cursor = proj_base; |
| |
| match elem { |
| ProjectionElem::Field(..) => { |
| let ty = |
| Place::ty_from(&place.base, proj_base, &self.body.local_decls, self.tcx) |
| .ty; |
| match ty.kind { |
| ty::Adt(def, _) => match self.tcx.layout_scalar_valid_range(def.did) { |
| (Bound::Unbounded, Bound::Unbounded) => {}, |
| _ => { |
| let (description, details) = if is_mut_use { |
| ( |
| "mutation of layout constrained field", |
| "mutating layout constrained fields cannot statically be \ |
| checked for valid values", |
| ) |
| } else { |
| ( |
| "borrow of layout constrained field with interior \ |
| mutability", |
| "references to fields of layout constrained fields \ |
| lose the constraints. Coupled with interior mutability, \ |
| the field can be changed to invalid values", |
| ) |
| }; |
| let source_info = self.source_info; |
| self.register_violations(&[UnsafetyViolation { |
| source_info, |
| description: Symbol::intern(description), |
| details: Symbol::intern(details), |
| kind: UnsafetyViolationKind::GeneralAndConstFn, |
| }], &[]); |
| } |
| }, |
| _ => {} |
| } |
| } |
| _ => {} |
| } |
| } |
| } |
| } |
| |
| pub(crate) fn provide(providers: &mut Providers<'_>) { |
| *providers = Providers { |
| unsafety_check_result, |
| unsafe_derive_on_repr_packed, |
| ..*providers |
| }; |
| } |
| |
| struct UnusedUnsafeVisitor<'a> { |
| used_unsafe: &'a FxHashSet<hir::HirId>, |
| unsafe_blocks: &'a mut Vec<(hir::HirId, bool)>, |
| } |
| |
| impl<'a, 'tcx> hir::intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'a> { |
| fn nested_visit_map<'this>(&'this mut self) -> |
| hir::intravisit::NestedVisitorMap<'this, 'tcx> |
| { |
| hir::intravisit::NestedVisitorMap::None |
| } |
| |
| fn visit_block(&mut self, block: &'tcx hir::Block) { |
| hir::intravisit::walk_block(self, block); |
| |
| if let hir::UnsafeBlock(hir::UserProvided) = block.rules { |
| self.unsafe_blocks.push((block.hir_id, self.used_unsafe.contains(&block.hir_id))); |
| } |
| } |
| } |
| |
| fn check_unused_unsafe( |
| tcx: TyCtxt<'_>, |
| def_id: DefId, |
| used_unsafe: &FxHashSet<hir::HirId>, |
| unsafe_blocks: &mut Vec<(hir::HirId, bool)>, |
| ) { |
| let body_id = |
| tcx.hir().as_local_hir_id(def_id).and_then(|hir_id| { |
| tcx.hir().maybe_body_owned_by(hir_id) |
| }); |
| |
| let body_id = match body_id { |
| Some(body) => body, |
| None => { |
| debug!("check_unused_unsafe({:?}) - no body found", def_id); |
| return |
| } |
| }; |
| let body = tcx.hir().body(body_id); |
| debug!("check_unused_unsafe({:?}, body={:?}, used_unsafe={:?})", |
| def_id, body, used_unsafe); |
| |
| let mut visitor = UnusedUnsafeVisitor { used_unsafe, unsafe_blocks }; |
| hir::intravisit::Visitor::visit_body(&mut visitor, body); |
| } |
| |
| fn unsafety_check_result(tcx: TyCtxt<'_>, def_id: DefId) -> UnsafetyCheckResult { |
| debug!("unsafety_violations({:?})", def_id); |
| |
| // N.B., this borrow is valid because all the consumers of |
| // `mir_built` force this. |
| let body = &tcx.mir_built(def_id).borrow(); |
| |
| let param_env = tcx.param_env(def_id); |
| |
| let id = tcx.hir().as_local_hir_id(def_id).unwrap(); |
| let (const_context, min_const_fn) = match tcx.hir().body_owner_kind(id) { |
| hir::BodyOwnerKind::Closure => (false, false), |
| hir::BodyOwnerKind::Fn => (tcx.is_const_fn(def_id), tcx.is_min_const_fn(def_id)), |
| hir::BodyOwnerKind::Const | |
| hir::BodyOwnerKind::Static(_) => (true, false), |
| }; |
| let mut checker = UnsafetyChecker::new(const_context, min_const_fn, body, tcx, param_env); |
| // mir_built ensures that body has a computed cache, so we don't (and can't) attempt to |
| // recompute it here. |
| let body = body.unwrap_read_only(); |
| checker.visit_body(body); |
| |
| check_unused_unsafe(tcx, def_id, &checker.used_unsafe, &mut checker.inherited_blocks); |
| UnsafetyCheckResult { |
| violations: checker.violations.into(), |
| unsafe_blocks: checker.inherited_blocks.into() |
| } |
| } |
| |
| fn unsafe_derive_on_repr_packed(tcx: TyCtxt<'_>, def_id: DefId) { |
| let lint_hir_id = tcx.hir().as_local_hir_id(def_id).unwrap_or_else(|| |
| bug!("checking unsafety for non-local def id {:?}", def_id)); |
| |
| // FIXME: when we make this a hard error, this should have its |
| // own error code. |
| let message = if tcx.generics_of(def_id).own_requires_monomorphization() { |
| "`#[derive]` can't be used on a `#[repr(packed)]` struct with \ |
| type or const parameters (error E0133)".to_string() |
| } else { |
| "`#[derive]` can't be used on a `#[repr(packed)]` struct that \ |
| does not derive Copy (error E0133)".to_string() |
| }; |
| tcx.lint_hir(SAFE_PACKED_BORROWS, |
| lint_hir_id, |
| tcx.def_span(def_id), |
| &message); |
| } |
| |
| /// Returns the `HirId` for an enclosing scope that is also `unsafe`. |
| fn is_enclosed( |
| tcx: TyCtxt<'_>, |
| used_unsafe: &FxHashSet<hir::HirId>, |
| id: hir::HirId, |
| ) -> Option<(String, hir::HirId)> { |
| let parent_id = tcx.hir().get_parent_node(id); |
| if parent_id != id { |
| if used_unsafe.contains(&parent_id) { |
| Some(("block".to_string(), parent_id)) |
| } else if let Some(Node::Item(&hir::Item { |
| kind: hir::ItemKind::Fn(ref sig, _, _), |
| .. |
| })) = tcx.hir().find(parent_id) { |
| match sig.header.unsafety { |
| hir::Unsafety::Unsafe => Some(("fn".to_string(), parent_id)), |
| hir::Unsafety::Normal => None, |
| } |
| } else { |
| is_enclosed(tcx, used_unsafe, parent_id) |
| } |
| } else { |
| None |
| } |
| } |
| |
| fn report_unused_unsafe(tcx: TyCtxt<'_>, used_unsafe: &FxHashSet<hir::HirId>, id: hir::HirId) { |
| let span = tcx.sess.source_map().def_span(tcx.hir().span(id)); |
| let msg = "unnecessary `unsafe` block"; |
| let mut db = tcx.struct_span_lint_hir(UNUSED_UNSAFE, id, span, msg); |
| db.span_label(span, msg); |
| if let Some((kind, id)) = is_enclosed(tcx, used_unsafe, id) { |
| db.span_label(tcx.sess.source_map().def_span(tcx.hir().span(id)), |
| format!("because it's nested under this `unsafe` {}", kind)); |
| } |
| db.emit(); |
| } |
| |
| fn builtin_derive_def_id(tcx: TyCtxt<'_>, def_id: DefId) -> Option<DefId> { |
| debug!("builtin_derive_def_id({:?})", def_id); |
| if let Some(impl_def_id) = tcx.impl_of_method(def_id) { |
| if tcx.has_attr(impl_def_id, sym::automatically_derived) { |
| debug!("builtin_derive_def_id({:?}) - is {:?}", def_id, impl_def_id); |
| Some(impl_def_id) |
| } else { |
| debug!("builtin_derive_def_id({:?}) - not automatically derived", def_id); |
| None |
| } |
| } else { |
| debug!("builtin_derive_def_id({:?}) - not a method", def_id); |
| None |
| } |
| } |
| |
| pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: DefId) { |
| debug!("check_unsafety({:?})", def_id); |
| |
| // closures are handled by their parent fn. |
| if tcx.is_closure(def_id) { |
| return; |
| } |
| |
| let UnsafetyCheckResult { |
| violations, |
| unsafe_blocks |
| } = tcx.unsafety_check_result(def_id); |
| |
| for &UnsafetyViolation { |
| source_info, description, details, kind |
| } in violations.iter() { |
| // Report an error. |
| match kind { |
| UnsafetyViolationKind::GeneralAndConstFn | |
| UnsafetyViolationKind::General => { |
| struct_span_err!( |
| tcx.sess, source_info.span, E0133, |
| "{} is unsafe and requires unsafe function or block", description) |
| .span_label(source_info.span, &*description.as_str()) |
| .note(&details.as_str()) |
| .emit(); |
| } |
| UnsafetyViolationKind::BorrowPacked(lint_hir_id) => { |
| if let Some(impl_def_id) = builtin_derive_def_id(tcx, def_id) { |
| tcx.unsafe_derive_on_repr_packed(impl_def_id); |
| } else { |
| tcx.lint_node_note(SAFE_PACKED_BORROWS, |
| lint_hir_id, |
| source_info.span, |
| &format!("{} is unsafe and requires unsafe function or block \ |
| (error E0133)", description), |
| &details.as_str()); |
| } |
| } |
| } |
| } |
| |
| let mut unsafe_blocks: Vec<_> = unsafe_blocks.into_iter().collect(); |
| unsafe_blocks.sort_by_cached_key(|(hir_id, _)| tcx.hir().hir_to_node_id(*hir_id)); |
| let used_unsafe: FxHashSet<_> = unsafe_blocks.iter() |
| .flat_map(|&&(id, used)| used.then_some(id)) |
| .collect(); |
| for &(block_id, is_used) in unsafe_blocks { |
| if !is_used { |
| report_unused_unsafe(tcx, &used_unsafe, block_id); |
| } |
| } |
| } |
