diff options
Diffstat (limited to 'compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs')
| -rw-r--r-- | compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs | 203 |
1 files changed, 84 insertions, 119 deletions
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs index 952d27262..6ed8adb47 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs @@ -1,7 +1,7 @@ use crate::callee::{self, DeferredCallResolution}; use crate::method::{self, MethodCallee, SelfSource}; use crate::rvalue_scopes; -use crate::{BreakableCtxt, Diverges, Expectation, FnCtxt, LocalTy}; +use crate::{BreakableCtxt, Diverges, Expectation, FnCtxt, LocalTy, RawTy}; use rustc_data_structures::captures::Captures; use rustc_data_structures::fx::FxHashSet; use rustc_errors::{Applicability, Diagnostic, ErrorGuaranteed, MultiSpan}; @@ -10,6 +10,9 @@ use rustc_hir::def::{CtorOf, DefKind, Res}; use rustc_hir::def_id::DefId; use rustc_hir::lang_items::LangItem; use rustc_hir::{ExprKind, GenericArg, Node, QPath}; +use rustc_hir_analysis::astconv::generics::{ + check_generic_arg_count_for_call, create_substs_for_generic_args, +}; use rustc_hir_analysis::astconv::{ AstConv, CreateSubstsForGenericArgsCtxt, ExplicitLateBound, GenericArgCountMismatch, GenericArgCountResult, IsMethodCall, PathSeg, @@ -22,9 +25,9 @@ use rustc_middle::ty::error::TypeError; use rustc_middle::ty::fold::TypeFoldable; use rustc_middle::ty::visit::TypeVisitable; use rustc_middle::ty::{ - self, AdtKind, CanonicalUserType, DefIdTree, EarlyBinder, GenericParamDefKind, Ty, UserType, + self, AdtKind, CanonicalUserType, DefIdTree, GenericParamDefKind, Ty, UserType, }; -use rustc_middle::ty::{GenericArgKind, InternalSubsts, SubstsRef, UserSelfTy, UserSubsts}; +use rustc_middle::ty::{GenericArgKind, SubstsRef, UserSelfTy, UserSubsts}; use rustc_session::lint; use rustc_span::def_id::LocalDefId; use rustc_span::hygiene::DesugaringKind; @@ -161,47 +164,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { pub fn write_method_call(&self, hir_id: hir::HirId, method: MethodCallee<'tcx>) { self.write_resolution(hir_id, Ok((DefKind::AssocFn, method.def_id))); self.write_substs(hir_id, method.substs); - - // When the method is confirmed, the `method.substs` includes - // parameters from not just the method, but also the impl of - // the method -- in particular, the `Self` type will be fully - // resolved. However, those are not something that the "user - // specified" -- i.e., those types come from the inferred type - // of the receiver, not something the user wrote. So when we - // create the user-substs, we want to replace those earlier - // types with just the types that the user actually wrote -- - // that is, those that appear on the *method itself*. - // - // As an example, if the user wrote something like - // `foo.bar::<u32>(...)` -- the `Self` type here will be the - // type of `foo` (possibly adjusted), but we don't want to - // include that. We want just the `[_, u32]` part. - if !method.substs.is_empty() { - let method_generics = self.tcx.generics_of(method.def_id); - if !method_generics.params.is_empty() { - let user_type_annotation = self.probe(|_| { - let user_substs = UserSubsts { - substs: InternalSubsts::for_item(self.tcx, method.def_id, |param, _| { - let i = param.index as usize; - if i < method_generics.parent_count { - self.var_for_def(DUMMY_SP, param) - } else { - method.substs[i] - } - }), - user_self_ty: None, // not relevant here - }; - - self.canonicalize_user_type_annotation(UserType::TypeOf( - method.def_id, - user_substs, - )) - }); - - debug!("write_method_call: user_type_annotation={:?}", user_type_annotation); - self.write_user_type_annotation(hir_id, user_type_annotation); - } - } } pub fn write_substs(&self, node_id: hir::HirId, substs: SubstsRef<'tcx>) { @@ -333,22 +295,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } - /// Basically whenever we are converting from a type scheme into - /// the fn body space, we always want to normalize associated - /// types as well. This function combines the two. - fn instantiate_type_scheme<T>(&self, span: Span, substs: SubstsRef<'tcx>, value: T) -> T - where - T: TypeFoldable<'tcx>, - { - debug!("instantiate_type_scheme(value={:?}, substs={:?})", value, substs); - let value = EarlyBinder(value).subst(self.tcx, substs); - let result = self.normalize(span, value); - debug!("instantiate_type_scheme = {:?}", result); - result - } - - /// As `instantiate_type_scheme`, but for the bounds found in a - /// generic type scheme. + /// Instantiates and normalizes the bounds for a given item pub(in super::super) fn instantiate_bounds( &self, span: Span, @@ -425,23 +372,38 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } - pub fn to_ty(&self, ast_t: &hir::Ty<'_>) -> Ty<'tcx> { - let t = <dyn AstConv<'_>>::ast_ty_to_ty(self, ast_t); + pub fn handle_raw_ty(&self, span: Span, ty: Ty<'tcx>) -> RawTy<'tcx> { + RawTy { raw: ty, normalized: self.normalize(span, ty) } + } + + pub fn to_ty(&self, ast_t: &hir::Ty<'_>) -> RawTy<'tcx> { + let t = self.astconv().ast_ty_to_ty(ast_t); self.register_wf_obligation(t.into(), ast_t.span, traits::WellFormed(None)); - t + self.handle_raw_ty(ast_t.span, t) } pub fn to_ty_saving_user_provided_ty(&self, ast_ty: &hir::Ty<'_>) -> Ty<'tcx> { let ty = self.to_ty(ast_ty); debug!("to_ty_saving_user_provided_ty: ty={:?}", ty); - if Self::can_contain_user_lifetime_bounds(ty) { - let c_ty = self.canonicalize_response(UserType::Ty(ty)); + if Self::can_contain_user_lifetime_bounds(ty.raw) { + let c_ty = self.canonicalize_response(UserType::Ty(ty.raw)); debug!("to_ty_saving_user_provided_ty: c_ty={:?}", c_ty); self.typeck_results.borrow_mut().user_provided_types_mut().insert(ast_ty.hir_id, c_ty); } - ty + ty.normalized + } + + pub(super) fn user_substs_for_adt(ty: RawTy<'tcx>) -> UserSubsts<'tcx> { + match (ty.raw.kind(), ty.normalized.kind()) { + (ty::Adt(_, substs), _) => UserSubsts { substs, user_self_ty: None }, + (_, ty::Adt(adt, substs)) => UserSubsts { + substs, + user_self_ty: Some(UserSelfTy { impl_def_id: adt.did(), self_ty: ty.raw }), + }, + _ => bug!("non-adt type {:?}", ty), + } } pub fn array_length_to_const(&self, length: &hir::ArrayLen) -> ty::Const<'tcx> { @@ -711,12 +673,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // Note: this check is pessimistic, as the inference type could be matched with something other // than the opaque type, but then we need a new `TypeRelation` just for this specific case and // can't re-use `sup` below. - // See src/test/ui/impl-trait/hidden-type-is-opaque.rs and - // src/test/ui/impl-trait/hidden-type-is-opaque-2.rs for examples that hit this path. + // See tests/ui/impl-trait/hidden-type-is-opaque.rs and + // tests/ui/impl-trait/hidden-type-is-opaque-2.rs for examples that hit this path. if formal_ret.has_infer_types() { for ty in ret_ty.walk() { if let ty::subst::GenericArgKind::Type(ty) = ty.unpack() - && let ty::Opaque(def_id, _) = *ty.kind() + && let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = *ty.kind() && let Some(def_id) = def_id.as_local() && self.opaque_type_origin(def_id, DUMMY_SP).is_some() { return None; @@ -795,7 +757,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { qpath: &'tcx QPath<'tcx>, hir_id: hir::HirId, span: Span, - ) -> (Res, Option<Ty<'tcx>>, &'tcx [hir::PathSegment<'tcx>]) { + ) -> (Res, Option<RawTy<'tcx>>, &'tcx [hir::PathSegment<'tcx>]) { debug!( "resolve_ty_and_res_fully_qualified_call: qpath={:?} hir_id={:?} span={:?}", qpath, hir_id, span @@ -818,7 +780,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // to be object-safe. // We manually call `register_wf_obligation` in the success path // below. - (<dyn AstConv<'_>>::ast_ty_to_ty_in_path(self, qself), qself, segment) + let ty = self.astconv().ast_ty_to_ty_in_path(qself); + (self.handle_raw_ty(span, ty), qself, segment) } QPath::LangItem(..) => { bug!("`resolve_ty_and_res_fully_qualified_call` called on `LangItem`") @@ -826,7 +789,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }; if let Some(&cached_result) = self.typeck_results.borrow().type_dependent_defs().get(hir_id) { - self.register_wf_obligation(ty.into(), qself.span, traits::WellFormed(None)); + self.register_wf_obligation(ty.raw.into(), qself.span, traits::WellFormed(None)); // Return directly on cache hit. This is useful to avoid doubly reporting // errors with default match binding modes. See #44614. let def = cached_result.map_or(Res::Err, |(kind, def_id)| Res::Def(kind, def_id)); @@ -834,7 +797,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } let item_name = item_segment.ident; let result = self - .resolve_fully_qualified_call(span, item_name, ty, qself.span, hir_id) + .resolve_fully_qualified_call(span, item_name, ty.normalized, qself.span, hir_id) .or_else(|error| { let result = match error { method::MethodError::PrivateMatch(kind, def_id, _) => Ok((kind, def_id)), @@ -845,17 +808,22 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // a WF obligation for `dyn MyTrait` when method lookup fails. Otherwise, // register a WF obligation so that we can detect any additional // errors in the self type. - if !(matches!(error, method::MethodError::NoMatch(_)) && ty.is_trait()) { - self.register_wf_obligation(ty.into(), qself.span, traits::WellFormed(None)); + if !(matches!(error, method::MethodError::NoMatch(_)) && ty.normalized.is_trait()) { + self.register_wf_obligation( + ty.raw.into(), + qself.span, + traits::WellFormed(None), + ); } if item_name.name != kw::Empty { if let Some(mut e) = self.report_method_error( span, - ty, + ty.normalized, item_name, SelfSource::QPath(qself), error, None, + Expectation::NoExpectation, ) { e.emit(); } @@ -864,7 +832,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }); if result.is_ok() { - self.register_wf_obligation(ty.into(), qself.span, traits::WellFormed(None)); + self.register_wf_obligation(ty.raw.into(), qself.span, traits::WellFormed(None)); } // Write back the new resolution. @@ -1001,7 +969,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { pub fn instantiate_value_path( &self, segments: &[hir::PathSegment<'_>], - self_ty: Option<Ty<'tcx>>, + self_ty: Option<RawTy<'tcx>>, res: Res, span: Span, hir_id: hir::HirId, @@ -1010,8 +978,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let path_segs = match res { Res::Local(_) | Res::SelfCtor(_) => vec![], - Res::Def(kind, def_id) => <dyn AstConv<'_>>::def_ids_for_value_path_segments( - self, segments, self_ty, kind, def_id, + Res::Def(kind, def_id) => self.astconv().def_ids_for_value_path_segments( + segments, + self_ty.map(|ty| ty.raw), + kind, + def_id, + span, ), _ => bug!("instantiate_value_path on {:?}", res), }; @@ -1022,8 +994,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { Res::Def(DefKind::Ctor(CtorOf::Variant, _), _) if let Some(self_ty) = self_ty => { - let adt_def = self_ty.ty_adt_def().unwrap(); - user_self_ty = Some(UserSelfTy { impl_def_id: adt_def.did(), self_ty }); + let adt_def = self_ty.normalized.ty_adt_def().unwrap(); + user_self_ty = Some(UserSelfTy { impl_def_id: adt_def.did(), self_ty: self_ty.raw }); is_alias_variant_ctor = true; } Res::Def(DefKind::AssocFn | DefKind::AssocConst, def_id) => { @@ -1042,7 +1014,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // inherent impl, we need to record the // `T` for posterity (see `UserSelfTy` for // details). - let self_ty = self_ty.expect("UFCS sugared assoc missing Self"); + let self_ty = self_ty.expect("UFCS sugared assoc missing Self").raw; user_self_ty = Some(UserSelfTy { impl_def_id: container_id, self_ty }); } } @@ -1057,8 +1029,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // errors if type parameters are provided in an inappropriate place. let generic_segs: FxHashSet<_> = path_segs.iter().map(|PathSeg(_, index)| index).collect(); - let generics_has_err = <dyn AstConv<'_>>::prohibit_generics( - self, + let generics_has_err = self.astconv().prohibit_generics( segments.iter().enumerate().filter_map(|(index, seg)| { if !generic_segs.contains(&index) || is_alias_variant_ctor { Some(seg) @@ -1099,7 +1070,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // parameter internally, but we don't allow users to specify the // parameter's value explicitly, so we have to do some error- // checking here. - let arg_count = <dyn AstConv<'_>>::check_generic_arg_count_for_call( + let arg_count = check_generic_arg_count_for_call( tcx, span, def_id, @@ -1124,19 +1095,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { .unwrap_or(false); let (res, self_ctor_substs) = if let Res::SelfCtor(impl_def_id) = res { - let ty = self.normalize_ty(span, tcx.at(span).type_of(impl_def_id)); - match *ty.kind() { - ty::Adt(adt_def, substs) if adt_def.has_ctor() => { - let variant = adt_def.non_enum_variant(); - let (ctor_kind, ctor_def_id) = variant.ctor.unwrap(); - (Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id), Some(substs)) + let ty = self.handle_raw_ty(span, tcx.at(span).type_of(impl_def_id)); + match ty.normalized.ty_adt_def() { + Some(adt_def) if adt_def.has_ctor() => { + let (ctor_kind, ctor_def_id) = adt_def.non_enum_variant().ctor.unwrap(); + let new_res = Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id); + let user_substs = Self::user_substs_for_adt(ty); + user_self_ty = user_substs.user_self_ty; + (new_res, Some(user_substs.substs)) } _ => { let mut err = tcx.sess.struct_span_err( span, "the `Self` constructor can only be used with tuple or unit structs", ); - if let Some(adt_def) = ty.ty_adt_def() { + if let Some(adt_def) = ty.normalized.ty_adt_def() { match adt_def.adt_kind() { AdtKind::Enum => { err.help("did you mean to use one of the enum's variants?"); @@ -1160,10 +1133,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }; let def_id = res.def_id(); - // The things we are substituting into the type should not contain - // escaping late-bound regions, and nor should the base type scheme. - let ty = tcx.type_of(def_id); - let arg_count = GenericArgCountResult { explicit_late_bound, correct: if infer_args_for_err.is_empty() { @@ -1209,10 +1178,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { ) -> ty::GenericArg<'tcx> { match (¶m.kind, arg) { (GenericParamDefKind::Lifetime, GenericArg::Lifetime(lt)) => { - <dyn AstConv<'_>>::ast_region_to_region(self.fcx, lt, Some(param)).into() + self.fcx.astconv().ast_region_to_region(lt, Some(param)).into() } (GenericParamDefKind::Type { .. }, GenericArg::Type(ty)) => { - self.fcx.to_ty(ty).into() + self.fcx.to_ty(ty).raw.into() } (GenericParamDefKind::Const { .. }, GenericArg::Const(ct)) => { self.fcx.const_arg_to_const(&ct.value, param.def_id).into() @@ -1244,10 +1213,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // If we have a default, then we it doesn't matter that we're not // inferring the type arguments: we provide the default where any // is missing. - let default = tcx.bound_type_of(param.def_id); - self.fcx - .normalize_ty(self.span, default.subst(tcx, substs.unwrap())) - .into() + tcx.bound_type_of(param.def_id).subst(tcx, substs.unwrap()).into() } else { // If no type arguments were provided, we have to infer them. // This case also occurs as a result of some malformed input, e.g. @@ -1258,9 +1224,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } GenericParamDefKind::Const { has_default } => { if !infer_args && has_default { - tcx.bound_const_param_default(param.def_id) - .subst(tcx, substs.unwrap()) - .into() + tcx.const_param_default(param.def_id).subst(tcx, substs.unwrap()).into() } else { self.fcx.var_for_def(self.span, param) } @@ -1269,13 +1233,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } - let substs = self_ctor_substs.unwrap_or_else(|| { - <dyn AstConv<'_>>::create_substs_for_generic_args( + let substs_raw = self_ctor_substs.unwrap_or_else(|| { + create_substs_for_generic_args( tcx, def_id, &[], has_self, - self_ty, + self_ty.map(|s| s.raw), &arg_count, &mut CreateCtorSubstsContext { fcx: self, @@ -1286,17 +1250,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }, ) }); - assert!(!substs.has_escaping_bound_vars()); - assert!(!ty.has_escaping_bound_vars()); // First, store the "user substs" for later. - self.write_user_type_annotation_from_substs(hir_id, def_id, substs, user_self_ty); + self.write_user_type_annotation_from_substs(hir_id, def_id, substs_raw, user_self_ty); + + // Normalize only after registering type annotations. + let substs = self.normalize(span, substs_raw); self.add_required_obligations_for_hir(span, def_id, &substs, hir_id); // Substitute the values for the type parameters into the type of // the referenced item. - let ty_substituted = self.instantiate_type_scheme(span, &substs, ty); + let ty = tcx.bound_type_of(def_id); + assert!(!substs.has_escaping_bound_vars()); + assert!(!ty.0.has_escaping_bound_vars()); + let ty_substituted = self.normalize(span, ty.subst(tcx, substs)); if let Some(UserSelfTy { impl_def_id, self_ty }) = user_self_ty { // In the case of `Foo<T>::method` and `<Foo<T>>::method`, if `method` @@ -1304,9 +1272,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // type parameters, which we can infer by unifying the provided `Self` // with the substituted impl type. // This also occurs for an enum variant on a type alias. - let ty = tcx.type_of(impl_def_id); - - let impl_ty = self.instantiate_type_scheme(span, &substs, ty); + let impl_ty = self.normalize(span, tcx.bound_type_of(impl_def_id).subst(tcx, substs)); + let self_ty = self.normalize(span, self_ty); match self.at(&self.misc(span), self.param_env).eq(impl_ty, self_ty) { Ok(ok) => self.register_infer_ok_obligations(ok), Err(_) => { @@ -1455,9 +1422,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { pub(in super::super) fn expr_in_place(&self, mut expr_id: hir::HirId) -> bool { let mut contained_in_place = false; - while let hir::Node::Expr(parent_expr) = - self.tcx.hir().get(self.tcx.hir().get_parent_node(expr_id)) - { + while let hir::Node::Expr(parent_expr) = self.tcx.hir().get_parent(expr_id) { match &parent_expr.kind { hir::ExprKind::Assign(lhs, ..) | hir::ExprKind::AssignOp(_, lhs, ..) => { if lhs.hir_id == expr_id { |