| // Type resolution: the phase that finds all the types in the AST with |
| // unresolved type variables and replaces "ty_var" types with their |
| // substitutions. |
| |
| use crate::FnCtxt; |
| use rustc_data_structures::unord::ExtendUnord; |
| use rustc_errors::{ErrorGuaranteed, StashKey}; |
| use rustc_hir as hir; |
| use rustc_hir::intravisit::{self, Visitor}; |
| use rustc_infer::infer::error_reporting::TypeAnnotationNeeded::E0282; |
| use rustc_middle::ty::adjustment::{Adjust, Adjustment, PointerCoercion}; |
| use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable}; |
| use rustc_middle::ty::visit::TypeVisitableExt; |
| use rustc_middle::ty::{self, Ty, TyCtxt}; |
| use rustc_span::symbol::sym; |
| use rustc_span::Span; |
| |
| use std::mem; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Entry point |
| |
| // During type inference, partially inferred types are |
| // represented using Type variables (ty::Infer). These don't appear in |
| // the final TypeckResults since all of the types should have been |
| // inferred once typeck is done. |
| // When type inference is running however, having to update the typeck |
| // typeck results every time a new type is inferred would be unreasonably slow, |
| // so instead all of the replacement happens at the end in |
| // resolve_type_vars_in_body, which creates a new TypeTables which |
| // doesn't contain any inference types. |
| impl<'a, 'tcx> FnCtxt<'a, 'tcx> { |
| pub fn resolve_type_vars_in_body( |
| &self, |
| body: &'tcx hir::Body<'tcx>, |
| ) -> &'tcx ty::TypeckResults<'tcx> { |
| let item_def_id = self.tcx.hir().body_owner_def_id(body.id()); |
| |
| // This attribute causes us to dump some writeback information |
| // in the form of errors, which is used for unit tests. |
| let rustc_dump_user_args = self.tcx.has_attr(item_def_id, sym::rustc_dump_user_args); |
| |
| let mut wbcx = WritebackCx::new(self, body, rustc_dump_user_args); |
| for param in body.params { |
| wbcx.visit_node_id(param.pat.span, param.hir_id); |
| } |
| // Type only exists for constants and statics, not functions. |
| match self.tcx.hir().body_owner_kind(item_def_id) { |
| hir::BodyOwnerKind::Const { .. } | hir::BodyOwnerKind::Static(_) => { |
| let item_hir_id = self.tcx.hir().local_def_id_to_hir_id(item_def_id); |
| wbcx.visit_node_id(body.value.span, item_hir_id); |
| } |
| hir::BodyOwnerKind::Closure | hir::BodyOwnerKind::Fn => (), |
| } |
| wbcx.visit_body(body); |
| wbcx.visit_min_capture_map(); |
| wbcx.eval_closure_size(); |
| wbcx.visit_fake_reads_map(); |
| wbcx.visit_closures(); |
| wbcx.visit_liberated_fn_sigs(); |
| wbcx.visit_fru_field_types(); |
| wbcx.visit_opaque_types(); |
| wbcx.visit_coercion_casts(); |
| wbcx.visit_user_provided_tys(); |
| wbcx.visit_user_provided_sigs(); |
| wbcx.visit_coroutine_interior(); |
| wbcx.visit_offset_of_container_types(); |
| |
| wbcx.typeck_results.rvalue_scopes = |
| mem::take(&mut self.typeck_results.borrow_mut().rvalue_scopes); |
| |
| let used_trait_imports = |
| mem::take(&mut self.typeck_results.borrow_mut().used_trait_imports); |
| debug!("used_trait_imports({:?}) = {:?}", item_def_id, used_trait_imports); |
| wbcx.typeck_results.used_trait_imports = used_trait_imports; |
| |
| wbcx.typeck_results.treat_byte_string_as_slice = |
| mem::take(&mut self.typeck_results.borrow_mut().treat_byte_string_as_slice); |
| |
| debug!("writeback: typeck results for {:?} are {:#?}", item_def_id, wbcx.typeck_results); |
| |
| self.tcx.arena.alloc(wbcx.typeck_results) |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // The Writeback context. This visitor walks the HIR, checking the |
| // fn-specific typeck results to find references to types or regions. It |
| // resolves those regions to remove inference variables and writes the |
| // final result back into the master typeck results in the tcx. Here and |
| // there, it applies a few ad-hoc checks that were not convenient to |
| // do elsewhere. |
| |
| struct WritebackCx<'cx, 'tcx> { |
| fcx: &'cx FnCtxt<'cx, 'tcx>, |
| |
| typeck_results: ty::TypeckResults<'tcx>, |
| |
| body: &'tcx hir::Body<'tcx>, |
| |
| rustc_dump_user_args: bool, |
| } |
| |
| impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> { |
| fn new( |
| fcx: &'cx FnCtxt<'cx, 'tcx>, |
| body: &'tcx hir::Body<'tcx>, |
| rustc_dump_user_args: bool, |
| ) -> WritebackCx<'cx, 'tcx> { |
| let owner = body.id().hir_id.owner; |
| |
| let mut wbcx = WritebackCx { |
| fcx, |
| typeck_results: ty::TypeckResults::new(owner), |
| body, |
| rustc_dump_user_args, |
| }; |
| |
| // HACK: We specifically don't want the (opaque) error from tainting our |
| // inference context. That'll prevent us from doing opaque type inference |
| // later on in borrowck, which affects diagnostic spans pretty negatively. |
| if let Some(e) = fcx.tainted_by_errors() { |
| wbcx.typeck_results.tainted_by_errors = Some(e); |
| } |
| |
| wbcx |
| } |
| |
| fn tcx(&self) -> TyCtxt<'tcx> { |
| self.fcx.tcx |
| } |
| |
| fn write_ty_to_typeck_results(&mut self, hir_id: hir::HirId, ty: Ty<'tcx>) { |
| debug!("write_ty_to_typeck_results({:?}, {:?})", hir_id, ty); |
| assert!( |
| !ty.has_infer() && !ty.has_placeholders() && !ty.has_free_regions(), |
| "{ty} can't be put into typeck results" |
| ); |
| self.typeck_results.node_types_mut().insert(hir_id, ty); |
| } |
| |
| // Hacky hack: During type-checking, we treat *all* operators |
| // as potentially overloaded. But then, during writeback, if |
| // we observe that something like `a+b` is (known to be) |
| // operating on scalars, we clear the overload. |
| fn fix_scalar_builtin_expr(&mut self, e: &hir::Expr<'_>) { |
| match e.kind { |
| hir::ExprKind::Unary(hir::UnOp::Neg | hir::UnOp::Not, inner) => { |
| let inner_ty = self.typeck_results.node_type(inner.hir_id); |
| |
| if inner_ty.is_scalar() { |
| self.typeck_results.type_dependent_defs_mut().remove(e.hir_id); |
| self.typeck_results.node_args_mut().remove(e.hir_id); |
| } |
| } |
| hir::ExprKind::Binary(ref op, lhs, rhs) | hir::ExprKind::AssignOp(ref op, lhs, rhs) => { |
| let lhs_ty = self.typeck_results.node_type(lhs.hir_id); |
| let rhs_ty = self.typeck_results.node_type(rhs.hir_id); |
| |
| if lhs_ty.is_scalar() && rhs_ty.is_scalar() { |
| self.typeck_results.type_dependent_defs_mut().remove(e.hir_id); |
| self.typeck_results.node_args_mut().remove(e.hir_id); |
| |
| match e.kind { |
| hir::ExprKind::Binary(..) => { |
| if !op.node.is_by_value() { |
| let mut adjustments = self.typeck_results.adjustments_mut(); |
| if let Some(a) = adjustments.get_mut(lhs.hir_id) { |
| a.pop(); |
| } |
| if let Some(a) = adjustments.get_mut(rhs.hir_id) { |
| a.pop(); |
| } |
| } |
| } |
| hir::ExprKind::AssignOp(..) |
| if let Some(a) = |
| self.typeck_results.adjustments_mut().get_mut(lhs.hir_id) => |
| { |
| a.pop(); |
| } |
| _ => {} |
| } |
| } |
| } |
| _ => {} |
| } |
| } |
| |
| // (ouz-a 1005988): Normally `[T] : std::ops::Index<usize>` should be normalized |
| // into [T] but currently `Where` clause stops the normalization process for it, |
| // here we compare types of expr and base in a code without `Where` clause they would be equal |
| // if they are not we don't modify the expr, hence we bypass the ICE |
| fn is_builtin_index( |
| &mut self, |
| e: &hir::Expr<'_>, |
| base_ty: Ty<'tcx>, |
| index_ty: Ty<'tcx>, |
| ) -> bool { |
| if let Some(elem_ty) = base_ty.builtin_index() |
| && let Some(exp_ty) = self.typeck_results.expr_ty_opt(e) |
| { |
| elem_ty == exp_ty && index_ty == self.fcx.tcx.types.usize |
| } else { |
| false |
| } |
| } |
| |
| // Similar to operators, indexing is always assumed to be overloaded |
| // Here, correct cases where an indexing expression can be simplified |
| // to use builtin indexing because the index type is known to be |
| // usize-ish |
| fn fix_index_builtin_expr(&mut self, e: &hir::Expr<'_>) { |
| if let hir::ExprKind::Index(ref base, ref index, _) = e.kind { |
| // All valid indexing looks like this; might encounter non-valid indexes at this point. |
| let base_ty = self.typeck_results.expr_ty_adjusted_opt(base); |
| if base_ty.is_none() { |
| // When encountering `return [0][0]` outside of a `fn` body we can encounter a base |
| // that isn't in the type table. We assume more relevant errors have already been |
| // emitted, so we delay an ICE if none have. (#64638) |
| self.tcx().sess.delay_span_bug(e.span, format!("bad base: `{base:?}`")); |
| } |
| if let Some(base_ty) = base_ty |
| && let ty::Ref(_, base_ty_inner, _) = *base_ty.kind() |
| { |
| let index_ty = |
| self.typeck_results.expr_ty_adjusted_opt(index).unwrap_or_else(|| { |
| // When encountering `return [0][0]` outside of a `fn` body we would attempt |
| // to access an nonexistent index. We assume that more relevant errors will |
| // already have been emitted, so we only gate on this with an ICE if no |
| // error has been emitted. (#64638) |
| Ty::new_error_with_message( |
| self.fcx.tcx, |
| e.span, |
| format!("bad index {index:?} for base: `{base:?}`"), |
| ) |
| }); |
| if self.is_builtin_index(e, base_ty_inner, index_ty) { |
| // Remove the method call record |
| self.typeck_results.type_dependent_defs_mut().remove(e.hir_id); |
| self.typeck_results.node_args_mut().remove(e.hir_id); |
| |
| if let Some(a) = self.typeck_results.adjustments_mut().get_mut(base.hir_id) { |
| // Discard the need for a mutable borrow |
| |
| // Extra adjustment made when indexing causes a drop |
| // of size information - we need to get rid of it |
| // Since this is "after" the other adjustment to be |
| // discarded, we do an extra `pop()` |
| if let Some(Adjustment { |
| kind: Adjust::Pointer(PointerCoercion::Unsize), |
| .. |
| }) = a.pop() |
| { |
| // So the borrow discard actually happens here |
| a.pop(); |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Impl of Visitor for Resolver |
| // |
| // This is the master code which walks the AST. It delegates most of |
| // the heavy lifting to the generic visit and resolve functions |
| // below. In general, a function is made into a `visitor` if it must |
| // traffic in node-ids or update typeck results in the type context etc. |
| |
| impl<'cx, 'tcx> Visitor<'tcx> for WritebackCx<'cx, 'tcx> { |
| fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) { |
| match e.kind { |
| hir::ExprKind::Closure(&hir::Closure { body, .. }) => { |
| let body = self.fcx.tcx.hir().body(body); |
| for param in body.params { |
| self.visit_node_id(e.span, param.hir_id); |
| } |
| |
| self.visit_body(body); |
| } |
| hir::ExprKind::Struct(_, fields, _) => { |
| for field in fields { |
| self.visit_field_id(field.hir_id); |
| } |
| } |
| hir::ExprKind::Field(..) | hir::ExprKind::OffsetOf(..) => { |
| self.visit_field_id(e.hir_id); |
| } |
| hir::ExprKind::ConstBlock(anon_const) => { |
| self.visit_node_id(e.span, anon_const.hir_id); |
| |
| let body = self.tcx().hir().body(anon_const.body); |
| self.visit_body(body); |
| } |
| _ => {} |
| } |
| |
| self.visit_node_id(e.span, e.hir_id); |
| intravisit::walk_expr(self, e); |
| |
| self.fix_scalar_builtin_expr(e); |
| self.fix_index_builtin_expr(e); |
| } |
| |
| fn visit_generic_param(&mut self, p: &'tcx hir::GenericParam<'tcx>) { |
| match &p.kind { |
| hir::GenericParamKind::Lifetime { .. } => { |
| // Nothing to write back here |
| } |
| hir::GenericParamKind::Type { .. } | hir::GenericParamKind::Const { .. } => { |
| self.tcx().sess.delay_span_bug(p.span, format!("unexpected generic param: {p:?}")); |
| } |
| } |
| } |
| |
| fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) { |
| self.visit_node_id(b.span, b.hir_id); |
| intravisit::walk_block(self, b); |
| } |
| |
| fn visit_pat(&mut self, p: &'tcx hir::Pat<'tcx>) { |
| match p.kind { |
| hir::PatKind::Binding(..) => { |
| let typeck_results = self.fcx.typeck_results.borrow(); |
| if let Some(bm) = |
| typeck_results.extract_binding_mode(self.tcx().sess, p.hir_id, p.span) |
| { |
| self.typeck_results.pat_binding_modes_mut().insert(p.hir_id, bm); |
| } |
| } |
| hir::PatKind::Struct(_, fields, _) => { |
| for field in fields { |
| self.visit_field_id(field.hir_id); |
| } |
| } |
| _ => {} |
| }; |
| |
| self.visit_pat_adjustments(p.span, p.hir_id); |
| |
| self.visit_node_id(p.span, p.hir_id); |
| intravisit::walk_pat(self, p); |
| } |
| |
| fn visit_local(&mut self, l: &'tcx hir::Local<'tcx>) { |
| intravisit::walk_local(self, l); |
| let var_ty = self.fcx.local_ty(l.span, l.hir_id); |
| let var_ty = self.resolve(var_ty, &l.span); |
| self.write_ty_to_typeck_results(l.hir_id, var_ty); |
| } |
| |
| fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) { |
| intravisit::walk_ty(self, hir_ty); |
| // If there are type checking errors, Type privacy pass will stop, |
| // so we may not get the type from hid_id, see #104513 |
| if let Some(ty) = self.fcx.node_ty_opt(hir_ty.hir_id) { |
| let ty = self.resolve(ty, &hir_ty.span); |
| self.write_ty_to_typeck_results(hir_ty.hir_id, ty); |
| } |
| } |
| |
| fn visit_infer(&mut self, inf: &'tcx hir::InferArg) { |
| intravisit::walk_inf(self, inf); |
| // Ignore cases where the inference is a const. |
| if let Some(ty) = self.fcx.node_ty_opt(inf.hir_id) { |
| let ty = self.resolve(ty, &inf.span); |
| self.write_ty_to_typeck_results(inf.hir_id, ty); |
| } |
| } |
| } |
| |
| impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> { |
| fn eval_closure_size(&mut self) { |
| self.tcx().with_stable_hashing_context(|ref hcx| { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| |
| self.typeck_results.closure_size_eval = fcx_typeck_results |
| .closure_size_eval |
| .to_sorted(hcx, false) |
| .into_iter() |
| .map(|(&closure_def_id, data)| { |
| let closure_hir_id = self.tcx().hir().local_def_id_to_hir_id(closure_def_id); |
| let data = self.resolve(*data, &closure_hir_id); |
| (closure_def_id, data) |
| }) |
| .collect(); |
| }) |
| } |
| |
| fn visit_min_capture_map(&mut self) { |
| self.tcx().with_stable_hashing_context(|ref hcx| { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| |
| self.typeck_results.closure_min_captures = fcx_typeck_results |
| .closure_min_captures |
| .to_sorted(hcx, false) |
| .into_iter() |
| .map(|(&closure_def_id, root_min_captures)| { |
| let root_var_map_wb = root_min_captures |
| .iter() |
| .map(|(var_hir_id, min_list)| { |
| let min_list_wb = min_list |
| .iter() |
| .map(|captured_place| { |
| let locatable = |
| captured_place.info.path_expr_id.unwrap_or_else(|| { |
| self.tcx().hir().local_def_id_to_hir_id(closure_def_id) |
| }); |
| self.resolve(captured_place.clone(), &locatable) |
| }) |
| .collect(); |
| (*var_hir_id, min_list_wb) |
| }) |
| .collect(); |
| (closure_def_id, root_var_map_wb) |
| }) |
| .collect(); |
| }) |
| } |
| |
| fn visit_fake_reads_map(&mut self) { |
| self.tcx().with_stable_hashing_context(move |ref hcx| { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| |
| self.typeck_results.closure_fake_reads = fcx_typeck_results |
| .closure_fake_reads |
| .to_sorted(hcx, true) |
| .into_iter() |
| .map(|(&closure_def_id, fake_reads)| { |
| let resolved_fake_reads = fake_reads |
| .iter() |
| .map(|(place, cause, hir_id)| { |
| let locatable = self.tcx().hir().local_def_id_to_hir_id(closure_def_id); |
| let resolved_fake_read = self.resolve(place.clone(), &locatable); |
| (resolved_fake_read, *cause, *hir_id) |
| }) |
| .collect(); |
| |
| (closure_def_id, resolved_fake_reads) |
| }) |
| .collect(); |
| }); |
| } |
| |
| fn visit_closures(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| let common_hir_owner = fcx_typeck_results.hir_owner; |
| |
| let fcx_closure_kind_origins = |
| fcx_typeck_results.closure_kind_origins().items_in_stable_order(); |
| |
| for (local_id, origin) in fcx_closure_kind_origins { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| let place_span = origin.0; |
| let place = self.resolve(origin.1.clone(), &place_span); |
| self.typeck_results.closure_kind_origins_mut().insert(hir_id, (place_span, place)); |
| } |
| } |
| |
| fn visit_coercion_casts(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| |
| let fcx_coercion_casts = fcx_typeck_results.coercion_casts().to_sorted_stable_ord(); |
| for local_id in fcx_coercion_casts { |
| self.typeck_results.set_coercion_cast(local_id); |
| } |
| } |
| |
| fn visit_user_provided_tys(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| let common_hir_owner = fcx_typeck_results.hir_owner; |
| |
| if self.rustc_dump_user_args { |
| let sorted_user_provided_types = |
| fcx_typeck_results.user_provided_types().items_in_stable_order(); |
| |
| let mut errors_buffer = Vec::new(); |
| for (local_id, c_ty) in sorted_user_provided_types { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| |
| if let ty::UserType::TypeOf(_, user_args) = c_ty.value { |
| // This is a unit-testing mechanism. |
| let span = self.tcx().hir().span(hir_id); |
| // We need to buffer the errors in order to guarantee a consistent |
| // order when emitting them. |
| let err = |
| self.tcx().sess.struct_span_err(span, format!("user args: {user_args:?}")); |
| err.buffer(&mut errors_buffer); |
| } |
| } |
| |
| if !errors_buffer.is_empty() { |
| errors_buffer.sort_by_key(|diag| diag.span.primary_span()); |
| for mut diag in errors_buffer { |
| self.tcx().sess.diagnostic().emit_diagnostic(&mut diag); |
| } |
| } |
| } |
| |
| self.typeck_results.user_provided_types_mut().extend( |
| fcx_typeck_results.user_provided_types().items().map(|(local_id, c_ty)| { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| |
| if cfg!(debug_assertions) && c_ty.has_infer() { |
| span_bug!( |
| hir_id.to_span(self.fcx.tcx), |
| "writeback: `{:?}` has inference variables", |
| c_ty |
| ); |
| }; |
| |
| (hir_id, *c_ty) |
| }), |
| ); |
| } |
| |
| fn visit_user_provided_sigs(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| |
| self.typeck_results.user_provided_sigs.extend_unord( |
| fcx_typeck_results.user_provided_sigs.items().map(|(&def_id, c_sig)| { |
| if cfg!(debug_assertions) && c_sig.has_infer() { |
| span_bug!( |
| self.fcx.tcx.def_span(def_id), |
| "writeback: `{:?}` has inference variables", |
| c_sig |
| ); |
| }; |
| |
| (def_id, *c_sig) |
| }), |
| ); |
| } |
| |
| fn visit_coroutine_interior(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| self.tcx().with_stable_hashing_context(move |ref hcx| { |
| for (&expr_def_id, predicates) in |
| fcx_typeck_results.coroutine_interior_predicates.to_sorted(hcx, false).into_iter() |
| { |
| let predicates = |
| self.resolve(predicates.clone(), &self.fcx.tcx.def_span(expr_def_id)); |
| self.typeck_results.coroutine_interior_predicates.insert(expr_def_id, predicates); |
| } |
| }) |
| } |
| |
| #[instrument(skip(self), level = "debug")] |
| fn visit_opaque_types(&mut self) { |
| let opaque_types = self.fcx.infcx.take_opaque_types(); |
| for (opaque_type_key, decl) in opaque_types { |
| let hidden_type = self.resolve(decl.hidden_type, &decl.hidden_type.span); |
| let opaque_type_key = self.resolve(opaque_type_key, &decl.hidden_type.span); |
| |
| if let ty::Alias(ty::Opaque, alias_ty) = hidden_type.ty.kind() |
| && alias_ty.def_id == opaque_type_key.def_id.to_def_id() |
| && alias_ty.args == opaque_type_key.args |
| { |
| continue; |
| } |
| |
| // Here we only detect impl trait definition conflicts when they |
| // are equal modulo regions. |
| if let Some(last_opaque_ty) = |
| self.typeck_results.concrete_opaque_types.insert(opaque_type_key, hidden_type) |
| && last_opaque_ty.ty != hidden_type.ty |
| { |
| assert!(!self.fcx.next_trait_solver()); |
| hidden_type |
| .report_mismatch(&last_opaque_ty, opaque_type_key.def_id, self.tcx()) |
| .stash( |
| self.tcx().def_span(opaque_type_key.def_id), |
| StashKey::OpaqueHiddenTypeMismatch, |
| ); |
| } |
| } |
| } |
| |
| fn visit_field_id(&mut self, hir_id: hir::HirId) { |
| if let Some(index) = self.fcx.typeck_results.borrow_mut().field_indices_mut().remove(hir_id) |
| { |
| self.typeck_results.field_indices_mut().insert(hir_id, index); |
| } |
| } |
| |
| #[instrument(skip(self, span), level = "debug")] |
| fn visit_node_id(&mut self, span: Span, hir_id: hir::HirId) { |
| // Export associated path extensions and method resolutions. |
| if let Some(def) = |
| self.fcx.typeck_results.borrow_mut().type_dependent_defs_mut().remove(hir_id) |
| { |
| self.typeck_results.type_dependent_defs_mut().insert(hir_id, def); |
| } |
| |
| // Resolve any borrowings for the node with id `node_id` |
| self.visit_adjustments(span, hir_id); |
| |
| // Resolve the type of the node with id `node_id` |
| let n_ty = self.fcx.node_ty(hir_id); |
| let n_ty = self.resolve(n_ty, &span); |
| self.write_ty_to_typeck_results(hir_id, n_ty); |
| debug!(?n_ty); |
| |
| // Resolve any substitutions |
| if let Some(args) = self.fcx.typeck_results.borrow().node_args_opt(hir_id) { |
| let args = self.resolve(args, &span); |
| debug!("write_args_to_tcx({:?}, {:?})", hir_id, args); |
| assert!(!args.has_infer() && !args.has_placeholders()); |
| self.typeck_results.node_args_mut().insert(hir_id, args); |
| } |
| } |
| |
| #[instrument(skip(self, span), level = "debug")] |
| fn visit_adjustments(&mut self, span: Span, hir_id: hir::HirId) { |
| let adjustment = self.fcx.typeck_results.borrow_mut().adjustments_mut().remove(hir_id); |
| match adjustment { |
| None => { |
| debug!("no adjustments for node"); |
| } |
| |
| Some(adjustment) => { |
| let resolved_adjustment = self.resolve(adjustment, &span); |
| debug!(?resolved_adjustment); |
| self.typeck_results.adjustments_mut().insert(hir_id, resolved_adjustment); |
| } |
| } |
| } |
| |
| #[instrument(skip(self, span), level = "debug")] |
| fn visit_pat_adjustments(&mut self, span: Span, hir_id: hir::HirId) { |
| let adjustment = self.fcx.typeck_results.borrow_mut().pat_adjustments_mut().remove(hir_id); |
| match adjustment { |
| None => { |
| debug!("no pat_adjustments for node"); |
| } |
| |
| Some(adjustment) => { |
| let resolved_adjustment = self.resolve(adjustment, &span); |
| debug!(?resolved_adjustment); |
| self.typeck_results.pat_adjustments_mut().insert(hir_id, resolved_adjustment); |
| } |
| } |
| } |
| |
| fn visit_liberated_fn_sigs(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| let common_hir_owner = fcx_typeck_results.hir_owner; |
| |
| let fcx_liberated_fn_sigs = fcx_typeck_results.liberated_fn_sigs().items_in_stable_order(); |
| |
| for (local_id, &fn_sig) in fcx_liberated_fn_sigs { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| let fn_sig = self.resolve(fn_sig, &hir_id); |
| self.typeck_results.liberated_fn_sigs_mut().insert(hir_id, fn_sig); |
| } |
| } |
| |
| fn visit_fru_field_types(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| let common_hir_owner = fcx_typeck_results.hir_owner; |
| |
| let fcx_fru_field_types = fcx_typeck_results.fru_field_types().items_in_stable_order(); |
| |
| for (local_id, ftys) in fcx_fru_field_types { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| let ftys = self.resolve(ftys.clone(), &hir_id); |
| self.typeck_results.fru_field_types_mut().insert(hir_id, ftys); |
| } |
| } |
| |
| fn visit_offset_of_container_types(&mut self) { |
| let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
| assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
| let common_hir_owner = fcx_typeck_results.hir_owner; |
| |
| for (local_id, &(container, ref indices)) in |
| fcx_typeck_results.offset_of_data().items_in_stable_order() |
| { |
| let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
| let container = self.resolve(container, &hir_id); |
| self.typeck_results.offset_of_data_mut().insert(hir_id, (container, indices.clone())); |
| } |
| } |
| |
| fn resolve<T>(&mut self, x: T, span: &dyn Locatable) -> T |
| where |
| T: TypeFoldable<TyCtxt<'tcx>>, |
| { |
| let mut resolver = Resolver::new(self.fcx, span, self.body); |
| let x = x.fold_with(&mut resolver); |
| if cfg!(debug_assertions) && x.has_infer() { |
| span_bug!(span.to_span(self.fcx.tcx), "writeback: `{:?}` has inference variables", x); |
| } |
| |
| // We may have introduced e.g. `ty::Error`, if inference failed, make sure |
| // to mark the `TypeckResults` as tainted in that case, so that downstream |
| // users of the typeck results don't produce extra errors, or worse, ICEs. |
| if let Some(e) = resolver.replaced_with_error { |
| self.typeck_results.tainted_by_errors = Some(e); |
| } |
| |
| x |
| } |
| } |
| |
| pub(crate) trait Locatable { |
| fn to_span(&self, tcx: TyCtxt<'_>) -> Span; |
| } |
| |
| impl Locatable for Span { |
| fn to_span(&self, _: TyCtxt<'_>) -> Span { |
| *self |
| } |
| } |
| |
| impl Locatable for hir::HirId { |
| fn to_span(&self, tcx: TyCtxt<'_>) -> Span { |
| tcx.hir().span(*self) |
| } |
| } |
| |
| /// The Resolver. This is the type folding engine that detects |
| /// unresolved types and so forth. |
| struct Resolver<'cx, 'tcx> { |
| fcx: &'cx FnCtxt<'cx, 'tcx>, |
| span: &'cx dyn Locatable, |
| body: &'tcx hir::Body<'tcx>, |
| |
| /// Set to `Some` if any `Ty` or `ty::Const` had to be replaced with an `Error`. |
| replaced_with_error: Option<ErrorGuaranteed>, |
| } |
| |
| impl<'cx, 'tcx> Resolver<'cx, 'tcx> { |
| fn new( |
| fcx: &'cx FnCtxt<'cx, 'tcx>, |
| span: &'cx dyn Locatable, |
| body: &'tcx hir::Body<'tcx>, |
| ) -> Resolver<'cx, 'tcx> { |
| Resolver { fcx, span, body, replaced_with_error: None } |
| } |
| |
| fn report_error(&self, p: impl Into<ty::GenericArg<'tcx>>) -> ErrorGuaranteed { |
| match self.fcx.tcx.sess.has_errors() { |
| Some(e) => e, |
| None => self |
| .fcx |
| .err_ctxt() |
| .emit_inference_failure_err( |
| self.fcx.tcx.hir().body_owner_def_id(self.body.id()), |
| self.span.to_span(self.fcx.tcx), |
| p.into(), |
| E0282, |
| false, |
| ) |
| .emit(), |
| } |
| } |
| } |
| |
| struct EraseEarlyRegions<'tcx> { |
| tcx: TyCtxt<'tcx>, |
| } |
| |
| impl<'tcx> TypeFolder<TyCtxt<'tcx>> for EraseEarlyRegions<'tcx> { |
| fn interner(&self) -> TyCtxt<'tcx> { |
| self.tcx |
| } |
| fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> { |
| if ty.has_type_flags(ty::TypeFlags::HAS_FREE_REGIONS) { |
| ty.super_fold_with(self) |
| } else { |
| ty |
| } |
| } |
| fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { |
| if r.is_late_bound() { r } else { self.tcx.lifetimes.re_erased } |
| } |
| } |
| |
| impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Resolver<'cx, 'tcx> { |
| fn interner(&self) -> TyCtxt<'tcx> { |
| self.fcx.tcx |
| } |
| |
| fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> { |
| match self.fcx.fully_resolve(t) { |
| Ok(t) if self.fcx.next_trait_solver() => { |
| // We must normalize erasing regions here, since later lints |
| // expect that types that show up in the typeck are fully |
| // normalized. |
| if let Ok(t) = self.fcx.tcx.try_normalize_erasing_regions(self.fcx.param_env, t) { |
| t |
| } else { |
| EraseEarlyRegions { tcx: self.fcx.tcx }.fold_ty(t) |
| } |
| } |
| Ok(t) => { |
| // Do not anonymize late-bound regions |
| // (e.g. keep `for<'a>` named `for<'a>`). |
| // This allows NLL to generate error messages that |
| // refer to the higher-ranked lifetime names written by the user. |
| EraseEarlyRegions { tcx: self.fcx.tcx }.fold_ty(t) |
| } |
| Err(_) => { |
| debug!("Resolver::fold_ty: input type `{:?}` not fully resolvable", t); |
| let e = self.report_error(t); |
| self.replaced_with_error = Some(e); |
| Ty::new_error(self.fcx.tcx, e) |
| } |
| } |
| } |
| |
| fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { |
| debug_assert!(!r.is_late_bound(), "Should not be resolving bound region."); |
| self.fcx.tcx.lifetimes.re_erased |
| } |
| |
| fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> { |
| match self.fcx.fully_resolve(ct) { |
| Ok(ct) => self.fcx.tcx.erase_regions(ct), |
| Err(_) => { |
| debug!("Resolver::fold_const: input const `{:?}` not fully resolvable", ct); |
| let e = self.report_error(ct); |
| self.replaced_with_error = Some(e); |
| ty::Const::new_error(self.fcx.tcx, e, ct.ty()) |
| } |
| } |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // During type check, we store promises with the result of trait |
| // lookup rather than the actual results (because the results are not |
| // necessarily available immediately). These routines unwind the |
| // promises. It is expected that we will have already reported any |
| // errors that may be encountered, so if the promises store an error, |
| // a dummy result is returned. |
