diff options
Diffstat (limited to 'compiler/rustc_borrowck/src')
10 files changed, 118 insertions, 24 deletions
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs index 0ceb63477c8..ee96dbc2f60 100644 --- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs @@ -7,7 +7,7 @@ use rustc_errors::{ }; use rustc_hir as hir; use rustc_hir::def_id::DefId; -use rustc_hir::intravisit::{walk_expr, Visitor}; +use rustc_hir::intravisit::{walk_block, walk_expr, Visitor}; use rustc_hir::{AsyncGeneratorKind, GeneratorKind}; use rustc_infer::infer::TyCtxtInferExt; use rustc_infer::traits::ObligationCause; @@ -23,7 +23,7 @@ use rustc_middle::ty::{ use rustc_mir_dataflow::move_paths::{InitKind, MoveOutIndex, MovePathIndex}; use rustc_span::hygiene::DesugaringKind; use rustc_span::symbol::sym; -use rustc_span::{BytePos, Span}; +use rustc_span::{BytePos, Span, Symbol}; use rustc_trait_selection::infer::InferCtxtExt; use rustc_trait_selection::traits::TraitEngineExt as _; @@ -1227,8 +1227,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { from_closure: false, region_name: RegionName { - source: - RegionNameSource::AnonRegionFromUpvar(upvar_span, ref upvar_name), + source: RegionNameSource::AnonRegionFromUpvar(upvar_span, upvar_name), .. }, span, @@ -1500,7 +1499,70 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { | BorrowExplanation::UsedLaterInLoop(..) | BorrowExplanation::UsedLaterWhenDropped { .. } => { // Only give this note and suggestion if it could be relevant. - err.note("consider using a `let` binding to create a longer lived value"); + let sm = self.infcx.tcx.sess.source_map(); + let mut suggested = false; + let msg = "consider using a `let` binding to create a longer lived value"; + + /// We check that there's a single level of block nesting to ensure always correct + /// suggestions. If we don't, then we only provide a free-form message to avoid + /// misleading users in cases like `src/test/ui/nll/borrowed-temporary-error.rs`. + /// We could expand the analysis to suggest hoising all of the relevant parts of + /// the users' code to make the code compile, but that could be too much. + struct NestedStatementVisitor { + span: Span, + current: usize, + found: usize, + } + + impl<'tcx> Visitor<'tcx> for NestedStatementVisitor { + fn visit_block(&mut self, block: &hir::Block<'tcx>) { + self.current += 1; + walk_block(self, block); + self.current -= 1; + } + fn visit_expr(&mut self, expr: &hir::Expr<'tcx>) { + if self.span == expr.span { + self.found = self.current; + } + walk_expr(self, expr); + } + } + let source_info = self.body.source_info(location); + if let Some(scope) = self.body.source_scopes.get(source_info.scope) + && let ClearCrossCrate::Set(scope_data) = &scope.local_data + && let Some(node) = self.infcx.tcx.hir().find(scope_data.lint_root) + && let Some(id) = node.body_id() + && let hir::ExprKind::Block(block, _) = self.infcx.tcx.hir().body(id).value.kind + { + for stmt in block.stmts { + let mut visitor = NestedStatementVisitor { + span: proper_span, + current: 0, + found: 0, + }; + visitor.visit_stmt(stmt); + if visitor.found == 0 + && stmt.span.contains(proper_span) + && let Some(p) = sm.span_to_margin(stmt.span) + && let Ok(s) = sm.span_to_snippet(proper_span) + { + let addition = format!("let binding = {};\n{}", s, " ".repeat(p)); + err.multipart_suggestion_verbose( + msg, + vec![ + (stmt.span.shrink_to_lo(), addition), + (proper_span, "binding".to_string()), + ], + Applicability::MaybeIncorrect, + ); + suggested = true; + break; + } + } + } + if !suggested { + err.note(msg); + } } _ => {} } @@ -1699,7 +1761,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { borrow_span: Span, name: &Option<String>, upvar_span: Span, - upvar_name: &str, + upvar_name: Symbol, escape_span: Span, ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> { let tcx = self.infcx.tcx; @@ -2093,7 +2155,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { } StorageDeadOrDrop::Destructor(_) => kind, }, - ProjectionElem::Field(..) | ProjectionElem::Downcast(..) => { + ProjectionElem::OpaqueCast { .. } + | ProjectionElem::Field(..) + | ProjectionElem::Downcast(..) => { match place_ty.ty.kind() { ty::Adt(def, _) if def.has_dtor(tcx) => { // Report the outermost adt with a destructor diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs index 230ccf51990..72aee0267ac 100644 --- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs +++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs @@ -12,7 +12,7 @@ use rustc_middle::mir::{ }; use rustc_middle::ty::adjustment::PointerCast; use rustc_middle::ty::{self, RegionVid, TyCtxt}; -use rustc_span::symbol::Symbol; +use rustc_span::symbol::{kw, Symbol}; use rustc_span::{sym, DesugaringKind, Span}; use crate::region_infer::BlameConstraint; @@ -282,7 +282,7 @@ impl<'tcx> BorrowExplanation<'tcx> { ) { if let ConstraintCategory::OpaqueType = category { let suggestable_name = - if region_name.was_named() { region_name.to_string() } else { "'_".to_string() }; + if region_name.was_named() { region_name.name } else { kw::UnderscoreLifetime }; let msg = format!( "you can add a bound to the {}to make it last less than `'static` and match `{}`", diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index 53c07a3d481..fada3d45fbe 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -226,6 +226,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { } ProjectionElem::Downcast(..) if including_downcast.0 => return None, ProjectionElem::Downcast(..) => (), + ProjectionElem::OpaqueCast(..) => (), ProjectionElem::Field(field, _ty) => { // FIXME(project-rfc_2229#36): print capture precisely here. if let Some(field) = self.is_upvar_field_projection(PlaceRef { @@ -286,6 +287,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { PlaceRef { local, projection: proj_base }.ty(self.body, self.infcx.tcx) } ProjectionElem::Downcast(..) => place.ty(self.body, self.infcx.tcx), + ProjectionElem::OpaqueCast(ty) => PlaceTy::from_ty(*ty), ProjectionElem::Field(_, field_type) => PlaceTy::from_ty(*field_type), }, }; diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs index 8134e122662..cb7077fe621 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs @@ -169,6 +169,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { .., ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } + | ProjectionElem::OpaqueCast { .. } | ProjectionElem::Subslice { .. } | ProjectionElem::Downcast(..), ], diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs index 6508c0da75f..0e6a05478a0 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs @@ -19,8 +19,7 @@ use rustc_middle::ty::subst::InternalSubsts; use rustc_middle::ty::Region; use rustc_middle::ty::TypeVisitor; use rustc_middle::ty::{self, RegionVid, Ty}; -use rustc_span::symbol::sym; -use rustc_span::symbol::Ident; +use rustc_span::symbol::{kw, sym, Ident}; use rustc_span::Span; use crate::borrowck_errors; @@ -758,7 +757,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { return; }; - let lifetime = if f.has_name() { fr_name.to_string() } else { "'_".to_string() }; + let lifetime = if f.has_name() { fr_name.name } else { kw::UnderscoreLifetime }; let arg = match param.param.pat.simple_ident() { Some(simple_ident) => format!("argument `{}`", simple_ident), @@ -770,7 +769,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> { self.infcx.tcx, diag, fn_returns, - lifetime, + lifetime.to_string(), Some(arg), captures, Some((param.param_ty_span, param.param_ty.to_string())), diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs index e41af17fbf9..4cf1ac4d7ab 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs @@ -34,13 +34,13 @@ pub(crate) enum RegionNameSource { /// The `'static` region. Static, /// The free region corresponding to the environment of a closure. - SynthesizedFreeEnvRegion(Span, String), + SynthesizedFreeEnvRegion(Span, &'static str), /// The region corresponding to an argument. AnonRegionFromArgument(RegionNameHighlight), /// The region corresponding to a closure upvar. - AnonRegionFromUpvar(Span, String), + AnonRegionFromUpvar(Span, Symbol), /// The region corresponding to the return type of a closure. - AnonRegionFromOutput(RegionNameHighlight, String), + AnonRegionFromOutput(RegionNameHighlight, &'static str), /// The region from a type yielded by a generator. AnonRegionFromYieldTy(Span, String), /// An anonymous region from an async fn. @@ -110,7 +110,7 @@ impl RegionName { } RegionNameSource::SynthesizedFreeEnvRegion(span, note) => { diag.span_label(*span, format!("lifetime `{self}` represents this closure's body")); - diag.note(note); + diag.note(*note); } RegionNameSource::AnonRegionFromArgument(RegionNameHighlight::CannotMatchHirTy( span, @@ -350,10 +350,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> { Some(RegionName { name: region_name, - source: RegionNameSource::SynthesizedFreeEnvRegion( - fn_decl_span, - note.to_string(), - ), + source: RegionNameSource::SynthesizedFreeEnvRegion(fn_decl_span, note), }) } @@ -678,7 +675,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> { Some(RegionName { name: region_name, - source: RegionNameSource::AnonRegionFromUpvar(upvar_span, upvar_name.to_string()), + source: RegionNameSource::AnonRegionFromUpvar(upvar_span, upvar_name), }) } @@ -756,7 +753,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> { Some(RegionName { name: self.synthesize_region_name(), - source: RegionNameSource::AnonRegionFromOutput(highlight, mir_description.to_string()), + source: RegionNameSource::AnonRegionFromOutput(highlight, mir_description), }) } diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs index e8673ecd3a0..74321ddcd99 100644 --- a/compiler/rustc_borrowck/src/lib.rs +++ b/compiler/rustc_borrowck/src/lib.rs @@ -1788,6 +1788,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { for (place_base, elem) in place.iter_projections().rev() { match elem { ProjectionElem::Index(_/*operand*/) | + ProjectionElem::OpaqueCast(_) | ProjectionElem::ConstantIndex { .. } | // assigning to P[i] requires P to be valid. ProjectionElem::Downcast(_/*adt_def*/, _/*variant_idx*/) => @@ -2179,6 +2180,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { | ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } + | ProjectionElem::OpaqueCast { .. } | ProjectionElem::Downcast(..) => { let upvar_field_projection = self.is_upvar_field_projection(place); if let Some(field) = upvar_field_projection { diff --git a/compiler/rustc_borrowck/src/places_conflict.rs b/compiler/rustc_borrowck/src/places_conflict.rs index 97335fd0dff..5b67e6aa1cf 100644 --- a/compiler/rustc_borrowck/src/places_conflict.rs +++ b/compiler/rustc_borrowck/src/places_conflict.rs @@ -255,6 +255,7 @@ fn place_components_conflict<'tcx>( | (ProjectionElem::Index { .. }, _, _) | (ProjectionElem::ConstantIndex { .. }, _, _) | (ProjectionElem::Subslice { .. }, _, _) + | (ProjectionElem::OpaqueCast { .. }, _, _) | (ProjectionElem::Downcast { .. }, _, _) => { // Recursive case. This can still be disjoint on a // further iteration if this a shallow access and @@ -322,6 +323,17 @@ fn place_projection_conflict<'tcx>( debug!("place_element_conflict: DISJOINT-OR-EQ-DEREF"); Overlap::EqualOrDisjoint } + (ProjectionElem::OpaqueCast(v1), ProjectionElem::OpaqueCast(v2)) => { + if v1 == v2 { + // same type - recur. + debug!("place_element_conflict: DISJOINT-OR-EQ-OPAQUE"); + Overlap::EqualOrDisjoint + } else { + // Different types. Disjoint! + debug!("place_element_conflict: DISJOINT-OPAQUE"); + Overlap::Disjoint + } + } (ProjectionElem::Field(f1, _), ProjectionElem::Field(f2, _)) => { if f1 == f2 { // same field (e.g., `a.y` vs. `a.y`) - recur. @@ -525,6 +537,7 @@ fn place_projection_conflict<'tcx>( | ProjectionElem::Field(..) | ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } + | ProjectionElem::OpaqueCast { .. } | ProjectionElem::Subslice { .. } | ProjectionElem::Downcast(..), _, diff --git a/compiler/rustc_borrowck/src/prefixes.rs b/compiler/rustc_borrowck/src/prefixes.rs index bdf2becb711..2b50cbac9a0 100644 --- a/compiler/rustc_borrowck/src/prefixes.rs +++ b/compiler/rustc_borrowck/src/prefixes.rs @@ -81,6 +81,7 @@ impl<'cx, 'tcx> Iterator for Prefixes<'cx, 'tcx> { } ProjectionElem::Downcast(..) | ProjectionElem::Subslice { .. } + | ProjectionElem::OpaqueCast { .. } | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Index(_) => { cursor = cursor_base; diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index cf2140097e6..8e763a02af3 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -790,6 +790,19 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { } PlaceTy::from_ty(fty) } + ProjectionElem::OpaqueCast(ty) => { + let ty = self.sanitize_type(place, ty); + let ty = self.cx.normalize(ty, location); + self.cx + .eq_types( + base.ty, + ty, + location.to_locations(), + ConstraintCategory::TypeAnnotation, + ) + .unwrap(); + PlaceTy::from_ty(ty) + } } } @@ -1195,10 +1208,11 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { tcx, self.param_env, proj, - |this, field, ()| { + |this, field, _| { let ty = this.field_ty(tcx, field); self.normalize(ty, locations) }, + |_, _| unreachable!(), ); curr_projected_ty = projected_ty; } @@ -2493,6 +2507,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { } ProjectionElem::Field(..) | ProjectionElem::Downcast(..) + | ProjectionElem::OpaqueCast(..) | ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => { |