diff options
Diffstat (limited to 'compiler/rustc_borrowck')
7 files changed, 58 insertions, 44 deletions
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs index 095c0df98ac..f9e52239d6f 100644 --- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs +++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs @@ -71,7 +71,6 @@ impl<'tcx> BorrowExplanation<'tcx> { ) { let tcx = cx.infcx.tcx; let body = cx.body; - let local_names = &cx.local_names; if let Some(span) = borrow_span { let def_id = body.source.def_id(); @@ -220,7 +219,7 @@ impl<'tcx> BorrowExplanation<'tcx> { _ => ("destructor", format!("type `{}`", local_decl.ty)), }; - match local_names[dropped_local] { + match cx.local_name(dropped_local) { Some(local_name) if !local_decl.from_compiler_desugaring() => { let message = format!( "{borrow_desc}borrow might be used here, when `{local_name}` is dropped \ @@ -670,10 +669,10 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> { Some(Cause::DropVar(local, location)) => { let mut should_note_order = false; - if self.local_names[local].is_some() + if self.local_name(local).is_some() && let Some((WriteKind::StorageDeadOrDrop, place)) = kind_place && let Some(borrowed_local) = place.as_local() - && self.local_names[borrowed_local].is_some() + && self.local_name(borrowed_local).is_some() && local != borrowed_local { should_note_order = true; @@ -748,7 +747,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> { Operand::Copy(place) | Operand::Move(place) => { if let Some(l) = place.as_local() { let local_decl = &self.body.local_decls[l]; - if self.local_names[l].is_none() { + if self.local_name(l).is_none() { local_decl.source_info.span } else { span @@ -793,7 +792,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> { Operand::Copy(place) | Operand::Move(place) => { if let Some(l) = place.as_local() { let local_decl = &self.body.local_decls[l]; - if self.local_names[l].is_none() { + if self.local_name(l).is_none() { local_decl.source_info.span } else { span diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index 5e3f3ffa2ea..7b4e38969ee 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -7,17 +7,17 @@ use rustc_data_structures::fx::FxIndexMap; use rustc_errors::{Applicability, Diag, EmissionGuarantee, MultiSpan, listify}; use rustc_hir::def::{CtorKind, Namespace}; use rustc_hir::{self as hir, CoroutineKind, LangItem}; -use rustc_index::IndexSlice; +use rustc_index::{IndexSlice, IndexVec}; use rustc_infer::infer::{BoundRegionConversionTime, NllRegionVariableOrigin}; use rustc_infer::traits::SelectionError; -use rustc_middle::bug; use rustc_middle::mir::{ AggregateKind, CallSource, ConstOperand, ConstraintCategory, FakeReadCause, Local, LocalInfo, LocalKind, Location, Operand, Place, PlaceRef, PlaceTy, ProjectionElem, Rvalue, Statement, - StatementKind, Terminator, TerminatorKind, find_self_call, + StatementKind, Terminator, TerminatorKind, VarDebugInfoContents, find_self_call, }; use rustc_middle::ty::print::Print; use rustc_middle::ty::{self, Ty, TyCtxt}; +use rustc_middle::{bug, span_bug}; use rustc_mir_dataflow::move_paths::{InitLocation, LookupResult, MoveOutIndex}; use rustc_span::def_id::LocalDefId; use rustc_span::source_map::Spanned; @@ -190,6 +190,36 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { ) -> Option<&(PlaceRef<'tcx>, Diag<'infcx>)> { self.diags_buffer.buffered_move_errors.get(move_out_indices) } + + /// Uses `body.var_debug_info` to find the symbol + fn local_name(&self, index: Local) -> Option<Symbol> { + *self.local_names().get(index)? + } + + fn local_names(&self) -> &IndexSlice<Local, Option<Symbol>> { + self.local_names.get_or_init(|| { + let mut local_names = IndexVec::from_elem(None, &self.body.local_decls); + for var_debug_info in &self.body.var_debug_info { + if let VarDebugInfoContents::Place(place) = var_debug_info.value { + if let Some(local) = place.as_local() { + if let Some(prev_name) = local_names[local] + && var_debug_info.name != prev_name + { + span_bug!( + var_debug_info.source_info.span, + "local {:?} has many names (`{}` vs `{}`)", + local, + prev_name, + var_debug_info.name + ); + } + local_names[local] = Some(var_debug_info.name); + } + } + } + local_names + }) + } } impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { @@ -430,7 +460,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { /// a name, or its name was generated by the compiler, then `Err` is returned fn append_local_to_string(&self, local: Local, buf: &mut String) -> Result<(), ()> { let decl = &self.body.local_decls[local]; - match self.local_names[local] { + match self.local_name(local) { Some(name) if !decl.from_compiler_desugaring() => { buf.push_str(name.as_str()); Ok(()) @@ -1500,4 +1530,9 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { } } } + + /// Skip over locals that begin with an underscore or have no name + pub(crate) fn local_excluded_from_unused_mut_lint(&self, index: Local) -> bool { + self.local_name(index).is_none_or(|name| name.as_str().starts_with('_')) + } } diff --git a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs index 52ed0f2a42c..b21d348183f 100644 --- a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs @@ -465,7 +465,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { if let PlaceRef { local, projection: [] } = deref_base { let decl = &self.body.local_decls[local]; - let local_name = self.local_names[local].map(|sym| format!("`{sym}`")); + let local_name = self.local_name(local).map(|sym| format!("`{sym}`")); if decl.is_ref_for_guard() { return self .cannot_move_out_of( @@ -829,7 +829,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { } if binds_to.len() == 1 { - let place_desc = self.local_names[*local].map(|sym| format!("`{sym}`")); + let place_desc = self.local_name(*local).map(|sym| format!("`{sym}`")); if let Some(expr) = self.find_expr(binding_span) { self.suggest_cloning(err, bind_to.ty, expr, None); diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs index a5c9bad3ac2..fd8a2a6bc35 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs @@ -60,7 +60,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { if access_place.as_local().is_some() { reason = ", as it is not declared as mutable".to_string(); } else { - let name = self.local_names[local].expect("immutable unnamed local"); + let name = self.local_name(local).expect("immutable unnamed local"); reason = format!(", as `{name}` is not declared as mutable"); } } @@ -285,7 +285,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { .body .local_decls .get(local) - .is_some_and(|l| mut_borrow_of_mutable_ref(l, self.local_names[local])) => + .is_some_and(|l| mut_borrow_of_mutable_ref(l, self.local_name(local))) => { let decl = &self.body.local_decls[local]; err.span_label(span, format!("cannot {act}")); @@ -481,7 +481,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { let (pointer_sigil, pointer_desc) = if local_decl.ty.is_ref() { ("&", "reference") } else { ("*const", "pointer") }; - match self.local_names[local] { + match self.local_name(local) { Some(name) if !local_decl.from_compiler_desugaring() => { err.span_label( span, diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs index 3bec07afa0f..d27e08573e0 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs @@ -664,14 +664,14 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { let fr_name_and_span = self.regioncx.get_var_name_and_span_for_region( self.infcx.tcx, self.body, - &self.local_names, + &self.local_names(), &self.upvars, errci.fr, ); let outlived_fr_name_and_span = self.regioncx.get_var_name_and_span_for_region( self.infcx.tcx, self.body, - &self.local_names, + &self.local_names(), &self.upvars, errci.outlived_fr, ); diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs index 487f78058a8..1ad629ad167 100644 --- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs +++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs @@ -399,7 +399,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> { [implicit_inputs + argument_index]; let (_, span) = self.regioncx.get_argument_name_and_span_for_region( self.body, - &self.local_names, + self.local_names(), argument_index, ); @@ -973,7 +973,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> { { let (arg_name, arg_span) = self.regioncx.get_argument_name_and_span_for_region( self.body, - &self.local_names, + self.local_names(), arg_index, ); let region_name = self.synthesize_region_name(); diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs index 4d85f109020..82b300dcb17 100644 --- a/compiler/rustc_borrowck/src/lib.rs +++ b/compiler/rustc_borrowck/src/lib.rs @@ -16,7 +16,7 @@ // tidy-alphabetical-end use std::borrow::Cow; -use std::cell::RefCell; +use std::cell::{OnceCell, RefCell}; use std::marker::PhantomData; use std::ops::{ControlFlow, Deref}; @@ -391,7 +391,7 @@ fn do_mir_borrowck<'tcx>( used_mut_upvars: SmallVec::new(), borrow_set: &borrow_set, upvars: &[], - local_names: IndexVec::from_elem(None, &promoted_body.local_decls), + local_names: OnceCell::from(IndexVec::from_elem(None, &promoted_body.local_decls)), region_names: RefCell::default(), next_region_name: RefCell::new(1), polonius_output: None, @@ -414,26 +414,6 @@ fn do_mir_borrowck<'tcx>( promoted_mbcx.report_move_errors(); } - let mut local_names = IndexVec::from_elem(None, &body.local_decls); - for var_debug_info in &body.var_debug_info { - if let VarDebugInfoContents::Place(place) = var_debug_info.value { - if let Some(local) = place.as_local() { - if let Some(prev_name) = local_names[local] - && var_debug_info.name != prev_name - { - span_bug!( - var_debug_info.source_info.span, - "local {:?} has many names (`{}` vs `{}`)", - local, - prev_name, - var_debug_info.name - ); - } - local_names[local] = Some(var_debug_info.name); - } - } - } - let mut mbcx = MirBorrowckCtxt { root_cx, infcx: &infcx, @@ -450,7 +430,7 @@ fn do_mir_borrowck<'tcx>( used_mut_upvars: SmallVec::new(), borrow_set: &borrow_set, upvars: tcx.closure_captures(def), - local_names, + local_names: OnceCell::new(), region_names: RefCell::default(), next_region_name: RefCell::new(1), move_errors: Vec::new(), @@ -682,7 +662,7 @@ struct MirBorrowckCtxt<'a, 'infcx, 'tcx> { upvars: &'tcx [&'tcx ty::CapturedPlace<'tcx>], /// Names of local (user) variables (extracted from `var_debug_info`). - local_names: IndexVec<Local, Option<Symbol>>, + local_names: OnceCell<IndexVec<Local, Option<Symbol>>>, /// Record the region names generated for each region in the given /// MIR def so that we can reuse them later in help/error messages. @@ -2610,7 +2590,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { }; // Skip over locals that begin with an underscore or have no name - if self.local_names[local].is_none_or(|name| name.as_str().starts_with('_')) { + if self.local_excluded_from_unused_mut_lint(local) { continue; } |