diff options
Diffstat (limited to 'compiler/rustc_hir_analysis')
32 files changed, 1772 insertions, 1398 deletions
diff --git a/compiler/rustc_hir_analysis/src/astconv/errors.rs b/compiler/rustc_hir_analysis/src/astconv/errors.rs index a9152bdc5..e6465d641 100644 --- a/compiler/rustc_hir_analysis/src/astconv/errors.rs +++ b/compiler/rustc_hir_analysis/src/astconv/errors.rs @@ -177,11 +177,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .all_traits() .filter(|trait_def_id| { let viz = self.tcx().visibility(*trait_def_id); - if let Some(def_id) = self.item_def_id() { - viz.is_accessible_from(def_id, self.tcx()) - } else { - viz.is_visible_locally() - } + let def_id = self.item_def_id(); + viz.is_accessible_from(def_id, self.tcx()) }) .collect(); diff --git a/compiler/rustc_hir_analysis/src/astconv/generics.rs b/compiler/rustc_hir_analysis/src/astconv/generics.rs index 47915b4bd..f64d65cc6 100644 --- a/compiler/rustc_hir_analysis/src/astconv/generics.rs +++ b/compiler/rustc_hir_analysis/src/astconv/generics.rs @@ -11,7 +11,6 @@ use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::DefId; use rustc_hir::GenericArg; -use rustc_infer::infer::TyCtxtInferExt; use rustc_middle::ty::{ self, subst, subst::SubstsRef, GenericParamDef, GenericParamDefKind, IsSuggestable, Ty, TyCtxt, }; @@ -83,9 +82,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { Res::Def(DefKind::TyParam, src_def_id) => { if let Some(param_local_id) = param.def_id.as_local() { let param_name = tcx.hir().ty_param_name(param_local_id); - let infcx = tcx.infer_ctxt().build(); - let param_type = - infcx.resolve_numeric_literals_with_default(tcx.type_of(param.def_id)); + let param_type = tcx.type_of(param.def_id); if param_type.is_suggestable(tcx, false) { err.span_suggestion( tcx.def_span(src_def_id), diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs index 38f195dab..78d204d47 100644 --- a/compiler/rustc_hir_analysis/src/astconv/mod.rs +++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs @@ -23,7 +23,6 @@ use rustc_hir as hir; use rustc_hir::def::{CtorOf, DefKind, Namespace, Res}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::intravisit::{walk_generics, Visitor as _}; -use rustc_hir::lang_items::LangItem; use rustc_hir::{GenericArg, GenericArgs, OpaqueTyOrigin}; use rustc_middle::middle::stability::AllowUnstable; use rustc_middle::ty::subst::{self, GenericArgKind, InternalSubsts, SubstsRef}; @@ -55,7 +54,7 @@ pub struct PathSeg(pub DefId, pub usize); pub trait AstConv<'tcx> { fn tcx<'a>(&'a self) -> TyCtxt<'tcx>; - fn item_def_id(&self) -> Option<DefId>; + fn item_def_id(&self) -> DefId; /// Returns predicates in scope of the form `X: Foo<T>`, where `X` /// is a type parameter `X` with the given id `def_id` and T @@ -110,13 +109,16 @@ pub trait AstConv<'tcx> { ) -> Ty<'tcx>; /// Normalize an associated type coming from the user. + /// + /// This should only be used by astconv. Use `FnCtxt::normalize` + /// or `ObligationCtxt::normalize` in downstream crates. fn normalize_ty(&self, span: Span, ty: Ty<'tcx>) -> Ty<'tcx>; /// Invoked when we encounter an error from some prior pass /// (e.g., resolve) that is translated into a ty-error. This is /// used to help suppress derived errors typeck might otherwise /// report. - fn set_tainted_by_errors(&self); + fn set_tainted_by_errors(&self, e: ErrorGuaranteed); fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, span: Span); } @@ -242,14 +244,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } None => { - self.re_infer(def, lifetime.span).unwrap_or_else(|| { + self.re_infer(def, lifetime.ident.span).unwrap_or_else(|| { debug!(?lifetime, "unelided lifetime in signature"); // This indicates an illegal lifetime // elision. `resolve_lifetime` should have // reported an error in this case -- but if // not, let's error out. - tcx.sess.delay_span_bug(lifetime.span, "unelided lifetime in signature"); + tcx.sess.delay_span_bug(lifetime.ident.span, "unelided lifetime in signature"); // Supply some dummy value. We don't have an // `re_error`, annoyingly, so use `'static`. @@ -275,7 +277,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { item_segment.args(), item_segment.infer_args, None, - None, + ty::BoundConstness::NotConst, ); if let Some(b) = item_segment.args().bindings.first() { Self::prohibit_assoc_ty_binding(self.tcx(), b.span); @@ -325,7 +327,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { generic_args: &'a hir::GenericArgs<'_>, infer_args: bool, self_ty: Option<Ty<'tcx>>, - constness: Option<ty::BoundConstness>, + constness: ty::BoundConstness, ) -> (SubstsRef<'tcx>, GenericArgCountResult) { // If the type is parameterized by this region, then replace this // region with the current anon region binding (in other words, @@ -345,7 +347,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { assert!(self_ty.is_some()); } } else { - assert!(self_ty.is_none() && parent_substs.is_empty()); + assert!(self_ty.is_none()); } let arg_count = Self::check_generic_arg_count( @@ -433,7 +435,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ty::Const::from_opt_const_arg_anon_const( tcx, ty::WithOptConstParam { - did: tcx.hir().local_def_id(ct.value.hir_id), + did: ct.value.def_id, const_param_did: Some(param.def_id), }, ) @@ -501,6 +503,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } GenericParamDefKind::Const { has_default } => { let ty = tcx.at(self.span).type_of(param.def_id); + if ty.references_error() { + return tcx.const_error(ty).into(); + } if !infer_args && has_default { tcx.bound_const_param_default(param.def_id) .subst(tcx, substs.unwrap()) @@ -536,7 +541,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { &mut substs_ctx, ); - if let Some(ty::BoundConstness::ConstIfConst) = constness + if let ty::BoundConstness::ConstIfConst = constness && generics.has_self && !tcx.has_attr(def_id, sym::const_trait) { tcx.sess.emit_err(crate::errors::ConstBoundForNonConstTrait { span } ); @@ -568,8 +573,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ConvertedBindingKind::Equality(self.ast_ty_to_ty(ty).into()) } hir::Term::Const(ref c) => { - let local_did = self.tcx().hir().local_def_id(c.hir_id); - let c = Const::from_anon_const(self.tcx(), local_did); + let c = Const::from_anon_const(self.tcx(), c.def_id); ConvertedBindingKind::Equality(c.into()) } }, @@ -609,7 +613,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { item_segment.args(), item_segment.infer_args, None, - None, + ty::BoundConstness::NotConst, ); if let Some(b) = item_segment.args().bindings.first() { @@ -639,7 +643,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty, trait_ref.path.segments.last().unwrap(), true, - Some(constness), + constness, ) } @@ -666,7 +670,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { args, infer_args, Some(self_ty), - Some(constness), + constness, ); let tcx = self.tcx(); @@ -796,7 +800,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty: Ty<'tcx>, trait_segment: &hir::PathSegment<'_>, is_impl: bool, - constness: Option<ty::BoundConstness>, + constness: ty::BoundConstness, ) -> ty::TraitRef<'tcx> { let (substs, _) = self.create_substs_for_ast_trait_ref( span, @@ -820,7 +824,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty: Ty<'tcx>, trait_segment: &'a hir::PathSegment<'a>, is_impl: bool, - constness: Option<ty::BoundConstness>, + constness: ty::BoundConstness, ) -> (SubstsRef<'tcx>, GenericArgCountResult) { self.complain_about_internal_fn_trait(span, trait_def_id, trait_segment, is_impl); @@ -849,12 +853,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .is_some() } - // Sets `implicitly_sized` to true on `Bounds` if necessary + /// Sets `implicitly_sized` to true on `Bounds` if necessary pub(crate) fn add_implicitly_sized<'hir>( &self, bounds: &mut Bounds<'hir>, ast_bounds: &'hir [hir::GenericBound<'hir>], - self_ty_where_predicates: Option<(hir::HirId, &'hir [hir::WherePredicate<'hir>])>, + self_ty_where_predicates: Option<(LocalDefId, &'hir [hir::WherePredicate<'hir>])>, span: Span, ) { let tcx = self.tcx(); @@ -874,19 +878,18 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; search_bounds(ast_bounds); if let Some((self_ty, where_clause)) = self_ty_where_predicates { - let self_ty_def_id = tcx.hir().local_def_id(self_ty).to_def_id(); for clause in where_clause { if let hir::WherePredicate::BoundPredicate(pred) = clause { - if pred.is_param_bound(self_ty_def_id) { + if pred.is_param_bound(self_ty.to_def_id()) { search_bounds(pred.bounds); } } } } - let sized_def_id = tcx.lang_items().require(LangItem::Sized); + let sized_def_id = tcx.lang_items().sized_trait(); match (&sized_def_id, unbound) { - (Ok(sized_def_id), Some(tpb)) + (Some(sized_def_id), Some(tpb)) if tpb.path.res == Res::Def(DefKind::Trait, *sized_def_id) => { // There was in fact a `?Sized` bound, return without doing anything @@ -906,7 +909,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // There was no `?Sized` bound; add implicitly sized if `Sized` is available. } } - if sized_def_id.is_err() { + if sized_def_id.is_none() { // No lang item for `Sized`, so we can't add it as a bound. return; } @@ -961,9 +964,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } hir::GenericBound::Outlives(lifetime) => { let region = self.ast_region_to_region(lifetime, None); - bounds - .region_bounds - .push((ty::Binder::bind_with_vars(region, bound_vars), lifetime.span)); + bounds.region_bounds.push(( + ty::Binder::bind_with_vars(region, bound_vars), + lifetime.ident.span, + )); } } } @@ -1199,7 +1203,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { (_, _) => { let got = if let Some(_) = term.ty() { "type" } else { "constant" }; let expected = def_kind.descr(assoc_item_def_id); - tcx.sess + let reported = tcx + .sess .struct_span_err( binding.span, &format!("expected {expected} bound, found {got}"), @@ -1210,11 +1215,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ) .emit(); term = match def_kind { - hir::def::DefKind::AssocTy => tcx.ty_error().into(), + hir::def::DefKind::AssocTy => { + tcx.ty_error_with_guaranteed(reported).into() + } hir::def::DefKind::AssocConst => tcx - .const_error( + .const_error_with_guaranteed( tcx.bound_type_of(assoc_item_def_id) .subst(tcx, projection_ty.skip_binder().substs), + reported, ) .into(), _ => unreachable!(), @@ -1332,8 +1340,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .map(|&(trait_ref, _, _)| trait_ref.def_id()) .find(|&trait_ref| tcx.is_trait_alias(trait_ref)) .map(|trait_ref| tcx.def_span(trait_ref)); - tcx.sess.emit_err(TraitObjectDeclaredWithNoTraits { span, trait_alias_span }); - return tcx.ty_error(); + let reported = + tcx.sess.emit_err(TraitObjectDeclaredWithNoTraits { span, trait_alias_span }); + return tcx.ty_error_with_guaranteed(reported); } // Check that there are no gross object safety violations; @@ -1343,14 +1352,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let object_safety_violations = astconv_object_safety_violations(tcx, item.trait_ref().def_id()); if !object_safety_violations.is_empty() { - report_object_safety_error( + let reported = report_object_safety_error( tcx, span, item.trait_ref().def_id(), &object_safety_violations, ) .emit(); - return tcx.ty_error(); + return tcx.ty_error_with_guaranteed(reported); } } @@ -1373,7 +1382,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let bound_predicate = obligation.predicate.kind(); match bound_predicate.skip_binder() { - ty::PredicateKind::Trait(pred) => { + ty::PredicateKind::Clause(ty::Clause::Trait(pred)) => { let pred = bound_predicate.rebind(pred); associated_types.entry(span).or_default().extend( tcx.associated_items(pred.def_id()) @@ -1382,7 +1391,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .map(|item| item.def_id), ); } - ty::PredicateKind::Projection(pred) => { + ty::PredicateKind::Clause(ty::Clause::Projection(pred)) => { let pred = bound_predicate.rebind(pred); // A `Self` within the original bound will be substituted with a // `trait_object_dummy_self`, so check for that. @@ -1812,7 +1821,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // Check if we have an enum variant. let mut variant_resolution = None; - if let ty::Adt(adt_def, _) = qself_ty.kind() { + if let ty::Adt(adt_def, adt_substs) = qself_ty.kind() { if adt_def.is_enum() { let variant_def = adt_def .variants() @@ -1908,6 +1917,22 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } } } + + // see if we can satisfy using an inherent associated type + for &impl_ in tcx.inherent_impls(adt_def.did()) { + let Some(assoc_ty_did) = self.lookup_assoc_ty(assoc_ident, hir_ref_id, span, impl_) else { + continue; + }; + let item_substs = self.create_substs_for_associated_item( + span, + assoc_ty_did, + assoc_segment, + adt_substs, + ); + let ty = tcx.bound_type_of(assoc_ty_did).subst(tcx, item_substs); + let ty = self.normalize_ty(span, ty); + return Ok((ty, DefKind::AssocTy, assoc_ty_did)); + } } // Find the type of the associated item, and the trait where the associated @@ -1977,7 +2002,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } err.emit() - } else if let Some(reported) = qself_ty.error_reported() { + } else if let Err(reported) = qself_ty.error_reported() { reported } else { // Don't print `TyErr` to the user. @@ -1993,37 +2018,17 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; let trait_did = bound.def_id(); - let (assoc_ident, def_scope) = - tcx.adjust_ident_and_get_scope(assoc_ident, trait_did, hir_ref_id); - - // We have already adjusted the item name above, so compare with `ident.normalize_to_macros_2_0()` instead - // of calling `filter_by_name_and_kind`. - let item = tcx.associated_items(trait_did).in_definition_order().find(|i| { - i.kind.namespace() == Namespace::TypeNS - && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident - }); - // Assume that if it's not matched, there must be a const defined with the same name - // but it was used in a type position. - let Some(item) = item else { + let Some(assoc_ty_did) = self.lookup_assoc_ty(assoc_ident, hir_ref_id, span, trait_did) else { + // Assume that if it's not matched, there must be a const defined with the same name + // but it was used in a type position. let msg = format!("found associated const `{assoc_ident}` when type was expected"); let guar = tcx.sess.struct_span_err(span, &msg).emit(); return Err(guar); }; - let ty = self.projected_ty_from_poly_trait_ref(span, item.def_id, assoc_segment, bound); + let ty = self.projected_ty_from_poly_trait_ref(span, assoc_ty_did, assoc_segment, bound); let ty = self.normalize_ty(span, ty); - let kind = DefKind::AssocTy; - if !item.visibility(tcx).is_accessible_from(def_scope, tcx) { - let kind = kind.descr(item.def_id); - let msg = format!("{} `{}` is private", kind, assoc_ident); - tcx.sess - .struct_span_err(span, &msg) - .span_label(span, &format!("private {}", kind)) - .emit(); - } - tcx.check_stability(item.def_id, Some(hir_ref_id), span, None); - if let Some(variant_def_id) = variant_resolution { tcx.struct_span_lint_hir( AMBIGUOUS_ASSOCIATED_ITEMS, @@ -2042,7 +2047,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; could_refer_to(DefKind::Variant, variant_def_id, ""); - could_refer_to(kind, item.def_id, " also"); + could_refer_to(DefKind::AssocTy, assoc_ty_did, " also"); lint.span_suggestion( span, @@ -2055,7 +2060,40 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }, ); } - Ok((ty, kind, item.def_id)) + Ok((ty, DefKind::AssocTy, assoc_ty_did)) + } + + fn lookup_assoc_ty( + &self, + ident: Ident, + block: hir::HirId, + span: Span, + scope: DefId, + ) -> Option<DefId> { + let tcx = self.tcx(); + let (ident, def_scope) = tcx.adjust_ident_and_get_scope(ident, scope, block); + + // We have already adjusted the item name above, so compare with `ident.normalize_to_macros_2_0()` instead + // of calling `find_by_name_and_kind`. + let item = tcx.associated_items(scope).in_definition_order().find(|i| { + i.kind.namespace() == Namespace::TypeNS + && i.ident(tcx).normalize_to_macros_2_0() == ident + })?; + + let kind = DefKind::AssocTy; + if !item.visibility(tcx).is_accessible_from(def_scope, tcx) { + let kind = kind.descr(item.def_id); + let msg = format!("{kind} `{ident}` is private"); + let def_span = self.tcx().def_span(item.def_id); + tcx.sess + .struct_span_err_with_code(span, &msg, rustc_errors::error_code!(E0624)) + .span_label(span, &format!("private {kind}")) + .span_label(def_span, &format!("{kind} defined here")) + .emit(); + } + tcx.check_stability(item.def_id, Some(block), span, None); + + Some(item.def_id) } fn qpath_to_ty( @@ -2080,17 +2118,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { debug!("qpath_to_ty: self.item_def_id()={:?}", def_id); - let parent_def_id = def_id - .and_then(|def_id| { - def_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id)) - }) + let parent_def_id = def_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id)) .map(|hir_id| tcx.hir().get_parent_item(hir_id).to_def_id()); debug!("qpath_to_ty: parent_def_id={:?}", parent_def_id); // If the trait in segment is the same as the trait defining the item, // use the `<Self as ..>` syntax in the error. - let is_part_of_self_trait_constraints = def_id == Some(trait_def_id); + let is_part_of_self_trait_constraints = def_id == trait_def_id; let is_part_of_fn_in_self_trait = parent_def_id == Some(trait_def_id); let type_name = if is_part_of_self_trait_constraints || is_part_of_fn_in_self_trait { @@ -2099,13 +2134,13 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { "Type" }; - self.report_ambiguous_associated_type( + let reported = self.report_ambiguous_associated_type( span, type_name, &path_str, item_segment.ident.name, ); - return tcx.ty_error(); + return tcx.ty_error_with_guaranteed(reported) }; debug!("qpath_to_ty: self_type={:?}", self_ty); @@ -2116,7 +2151,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty, trait_segment, false, - Some(constness), + constness, ); let item_substs = self.create_substs_for_associated_item( @@ -2365,7 +2400,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { path_segs } - // Check a type `Path` and convert it to a `Ty`. + /// Check a type `Path` and convert it to a `Ty`. pub fn res_to_ty( &self, opt_self_ty: Option<Ty<'tcx>>, @@ -2383,7 +2418,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { match path.res { Res::Def(DefKind::OpaqueTy | DefKind::ImplTraitPlaceholder, did) => { // Check for desugared `impl Trait`. - assert!(ty::is_impl_trait_defn(tcx, did).is_none()); + assert!(tcx.is_type_alias_impl_trait(did)); let item_segment = path.segments.split_last().unwrap(); self.prohibit_generics(item_segment.1.iter(), |err| { err.note("`impl Trait` types can't have type parameters"); @@ -2547,8 +2582,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { { err.span_note(impl_.self_ty.span, "not a concrete type"); } - err.emit(); - tcx.ty_error() + tcx.ty_error_with_guaranteed(err.emit()) } else { self.normalize_ty(span, ty) } @@ -2596,8 +2630,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } } Res::Err => { - self.set_tainted_by_errors(); - self.tcx().ty_error() + let e = self + .tcx() + .sess + .delay_span_bug(path.span, "path with `Res:Err` but no error emitted"); + self.set_tainted_by_errors(e); + self.tcx().ty_error_with_guaranteed(e) } _ => span_bug!(span, "unexpected resolution: {:?}", path.res), } @@ -2687,7 +2725,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { &GenericArgs::none(), true, None, - None, + ty::BoundConstness::NotConst, ); EarlyBinder(self.normalize_ty(span, tcx.at(span).type_of(def_id))) .subst(tcx, substs) @@ -2696,8 +2734,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let length = match length { &hir::ArrayLen::Infer(_, span) => self.ct_infer(tcx.types.usize, None, span), hir::ArrayLen::Body(constant) => { - let length_def_id = tcx.hir().local_def_id(constant.hir_id); - ty::Const::from_anon_const(tcx, length_def_id) + ty::Const::from_anon_const(tcx, constant.def_id) } }; @@ -2705,7 +2742,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self.normalize_ty(ast_ty.span, array_ty) } hir::TyKind::Typeof(ref e) => { - let ty_erased = tcx.type_of(tcx.hir().local_def_id(e.hir_id)); + let ty_erased = tcx.type_of(e.def_id); let ty = tcx.fold_regions(ty_erased, |r, _| { if r.is_erased() { tcx.lifetimes.re_static } else { r } }); @@ -2750,35 +2787,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let substs = InternalSubsts::for_item(tcx, def_id, |param, _| { if let Some(i) = (param.index as usize).checked_sub(generics.parent_count) { // Our own parameters are the resolved lifetimes. - if let GenericParamDefKind::Lifetime = param.kind { - if let hir::GenericArg::Lifetime(lifetime) = &lifetimes[i] { - self.ast_region_to_region(lifetime, None).into() - } else { - bug!() - } - } else { - bug!() - } + let GenericParamDefKind::Lifetime { .. } = param.kind else { bug!() }; + let hir::GenericArg::Lifetime(lifetime) = &lifetimes[i] else { bug!() }; + self.ast_region_to_region(lifetime, None).into() } else { - match param.kind { - // For RPIT (return position impl trait), only lifetimes - // mentioned in the impl Trait predicate are captured by - // the opaque type, so the lifetime parameters from the - // parent item need to be replaced with `'static`. - // - // For `impl Trait` in the types of statics, constants, - // locals and type aliases. These capture all parent - // lifetimes, so they can use their identity subst. - GenericParamDefKind::Lifetime - if matches!( - origin, - hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..) - ) => - { - tcx.lifetimes.re_static.into() - } - _ => tcx.mk_param_from_def(param), - } + tcx.mk_param_from_def(param) } }); debug!("impl_trait_ty_to_ty: substs={:?}", substs); @@ -2955,6 +2968,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { Some(tcx.liberate_late_bound_regions(fn_hir_id.expect_owner().to_def_id(), ty)) } + #[instrument(level = "trace", skip(self, generate_err))] fn validate_late_bound_regions( &self, constrained_regions: FxHashSet<ty::BoundRegionKind>, @@ -2963,7 +2977,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ) { for br in referenced_regions.difference(&constrained_regions) { let br_name = match *br { - ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(_) | ty::BrEnv => { + ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(..) | ty::BrEnv => { "an anonymous lifetime".to_string() } ty::BrNamed(_, name) => format!("lifetime `{}`", name), @@ -2971,7 +2985,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let mut err = generate_err(&br_name); - if let ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(_) = *br { + if let ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(..) = *br { // The only way for an anonymous lifetime to wind up // in the return type but **also** be unconstrained is // if it only appears in "associated types" in the @@ -2996,7 +3010,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { fn compute_object_lifetime_bound( &self, span: Span, - existential_predicates: &'tcx ty::List<ty::Binder<'tcx, ty::ExistentialPredicate<'tcx>>>, + existential_predicates: &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>, ) -> Option<ty::Region<'tcx>> // if None, use the default { let tcx = self.tcx(); diff --git a/compiler/rustc_hir_analysis/src/bounds.rs b/compiler/rustc_hir_analysis/src/bounds.rs index 6a28bb16a..3e3544ce6 100644 --- a/compiler/rustc_hir_analysis/src/bounds.rs +++ b/compiler/rustc_hir_analysis/src/bounds.rs @@ -60,13 +60,10 @@ impl<'tcx> Bounds<'tcx> { { // If it could be sized, and is, add the `Sized` predicate. let sized_predicate = self.implicitly_sized.and_then(|span| { - tcx.lang_items().sized_trait().map(move |sized| { - let trait_ref = ty::Binder::dummy(ty::TraitRef { - def_id: sized, - substs: tcx.mk_substs_trait(param_ty, &[]), - }); - (trait_ref.without_const().to_predicate(tcx), span) - }) + // FIXME: use tcx.at(span).mk_trait_ref(LangItem::Sized) here? This may make no-core code harder to write. + let sized = tcx.lang_items().sized_trait()?; + let trait_ref = ty::Binder::dummy(tcx.mk_trait_ref(sized, [param_ty])); + Some((trait_ref.without_const().to_predicate(tcx), span)) }); let region_preds = self.region_bounds.iter().map(move |&(region_bound, span)| { diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs index b70ac0205..fc0ca6209 100644 --- a/compiler/rustc_hir_analysis/src/check/check.rs +++ b/compiler/rustc_hir_analysis/src/check/check.rs @@ -1,4 +1,5 @@ use crate::check::intrinsicck::InlineAsmCtxt; +use crate::errors::LinkageType; use super::compare_method::check_type_bounds; use super::compare_method::{compare_impl_method, compare_ty_impl}; @@ -6,10 +7,11 @@ use super::*; use rustc_attr as attr; use rustc_errors::{Applicability, ErrorGuaranteed, MultiSpan}; use rustc_hir as hir; -use rustc_hir::def::{DefKind, Res}; +use rustc_hir::def::{CtorKind, DefKind, Res}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::intravisit::Visitor; use rustc_hir::{ItemKind, Node, PathSegment}; +use rustc_infer::infer::opaque_types::ConstrainOpaqueTypeRegionVisitor; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::{DefiningAnchor, RegionVariableOrigin, TyCtxtInferExt}; use rustc_infer::traits::Obligation; @@ -19,13 +21,12 @@ use rustc_middle::middle::stability::EvalResult; use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES}; use rustc_middle::ty::subst::GenericArgKind; use rustc_middle::ty::util::{Discr, IntTypeExt}; -use rustc_middle::ty::{ - self, ParamEnv, ToPredicate, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, -}; +use rustc_middle::ty::{self, AdtDef, ParamEnv, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable}; use rustc_session::lint::builtin::{UNINHABITED_STATIC, UNSUPPORTED_CALLING_CONVENTIONS}; use rustc_span::symbol::sym; use rustc_span::{self, Span}; use rustc_target::spec::abi::Abi; +use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedDirective; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _; use rustc_trait_selection::traits::{self, ObligationCtxt}; @@ -75,7 +76,7 @@ fn check_struct(tcx: TyCtxt<'_>, def_id: LocalDefId) { check_simd(tcx, span, def_id); } - check_transparent(tcx, span, def); + check_transparent(tcx, def); check_packed(tcx, span, def); } @@ -83,7 +84,7 @@ fn check_union(tcx: TyCtxt<'_>, def_id: LocalDefId) { let def = tcx.adt_def(def_id); let span = tcx.def_span(def_id); def.destructor(tcx); // force the destructor to be evaluated - check_transparent(tcx, span, def); + check_transparent(tcx, def); check_union_fields(tcx, span, def_id); check_packed(tcx, span, def); } @@ -230,7 +231,9 @@ fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { let substs = InternalSubsts::identity_for_item(tcx, item.owner_id.to_def_id()); let span = tcx.def_span(item.owner_id.def_id); - check_opaque_for_inheriting_lifetimes(tcx, item.owner_id.def_id, span); + if !tcx.features().impl_trait_projections { + check_opaque_for_inheriting_lifetimes(tcx, item.owner_id.def_id, span); + } if tcx.type_of(item.owner_id.def_id).references_error() { return; } @@ -239,6 +242,7 @@ fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { } check_opaque_meets_bounds(tcx, item.owner_id.def_id, substs, span, &origin); } + /// Checks that an opaque type does not use `Self` or `T::Foo` projections that would result /// in "inheriting lifetimes". #[instrument(level = "debug", skip(tcx, span))] @@ -250,39 +254,11 @@ pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>( let item = tcx.hir().expect_item(def_id); debug!(?item, ?span); - struct FoundParentLifetime; - struct FindParentLifetimeVisitor<'tcx>(&'tcx ty::Generics); - impl<'tcx> ty::visit::TypeVisitor<'tcx> for FindParentLifetimeVisitor<'tcx> { - type BreakTy = FoundParentLifetime; - - fn visit_region(&mut self, r: ty::Region<'tcx>) -> ControlFlow<Self::BreakTy> { - debug!("FindParentLifetimeVisitor: r={:?}", r); - if let ty::ReEarlyBound(ty::EarlyBoundRegion { index, .. }) = *r { - if index < self.0.parent_count as u32 { - return ControlFlow::Break(FoundParentLifetime); - } else { - return ControlFlow::CONTINUE; - } - } - - r.super_visit_with(self) - } - - fn visit_const(&mut self, c: ty::Const<'tcx>) -> ControlFlow<Self::BreakTy> { - if let ty::ConstKind::Unevaluated(..) = c.kind() { - // FIXME(#72219) We currently don't detect lifetimes within substs - // which would violate this check. Even though the particular substitution is not used - // within the const, this should still be fixed. - return ControlFlow::CONTINUE; - } - c.super_visit_with(self) - } - } - struct ProhibitOpaqueVisitor<'tcx> { tcx: TyCtxt<'tcx>, opaque_identity_ty: Ty<'tcx>, - generics: &'tcx ty::Generics, + parent_count: u32, + references_parent_regions: bool, selftys: Vec<(Span, Option<String>)>, } @@ -290,12 +266,25 @@ pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>( type BreakTy = Ty<'tcx>; fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> { - debug!("check_opaque_for_inheriting_lifetimes: (visit_ty) t={:?}", t); + debug!(?t, "root_visit_ty"); if t == self.opaque_identity_ty { ControlFlow::CONTINUE } else { - t.super_visit_with(&mut FindParentLifetimeVisitor(self.generics)) - .map_break(|FoundParentLifetime| t) + t.visit_with(&mut ConstrainOpaqueTypeRegionVisitor { + tcx: self.tcx, + op: |region| { + if let ty::ReEarlyBound(ty::EarlyBoundRegion { index, .. }) = *region + && index < self.parent_count + { + self.references_parent_regions= true; + } + }, + }); + if self.references_parent_regions { + ControlFlow::Break(t) + } else { + ControlFlow::CONTINUE + } } } } @@ -328,15 +317,20 @@ pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>( if let ItemKind::OpaqueTy(hir::OpaqueTy { origin: hir::OpaqueTyOrigin::AsyncFn(..) | hir::OpaqueTyOrigin::FnReturn(..), + in_trait, .. }) = item.kind { + let substs = InternalSubsts::identity_for_item(tcx, def_id.to_def_id()); + let opaque_identity_ty = if in_trait { + tcx.mk_projection(def_id.to_def_id(), substs) + } else { + tcx.mk_opaque(def_id.to_def_id(), substs) + }; let mut visitor = ProhibitOpaqueVisitor { - opaque_identity_ty: tcx.mk_opaque( - def_id.to_def_id(), - InternalSubsts::identity_for_item(tcx, def_id.to_def_id()), - ), - generics: tcx.generics_of(def_id), + opaque_identity_ty, + parent_count: tcx.generics_of(def_id).parent_count as u32, + references_parent_regions: false, tcx, selftys: vec![], }; @@ -344,10 +338,6 @@ pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>( .explicit_item_bounds(def_id) .iter() .try_for_each(|(predicate, _)| predicate.visit_with(&mut visitor)); - debug!( - "check_opaque_for_inheriting_lifetimes: prohibit_opaque={:?}, visitor.opaque_identity_ty={:?}, visitor.generics={:?}", - prohibit_opaque, visitor.opaque_identity_ty, visitor.generics - ); if let Some(ty) = prohibit_opaque.break_value() { visitor.visit_item(&item); @@ -358,15 +348,16 @@ pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>( _ => unreachable!(), }; - let mut err = struct_span_err!( - tcx.sess, + let mut err = feature_err( + &tcx.sess.parse_sess, + sym::impl_trait_projections, span, - E0760, - "`{}` return type cannot contain a projection or `Self` that references lifetimes from \ - a parent scope", - if is_async { "async fn" } else { "impl Trait" }, + &format!( + "`{}` return type cannot contain a projection or `Self` that references \ + lifetimes from a parent scope", + if is_async { "async fn" } else { "impl Trait" }, + ), ); - for (span, name) in visitor.selftys { err.span_suggestion( span, @@ -450,8 +441,8 @@ fn check_opaque_meets_bounds<'tcx>( let misc_cause = traits::ObligationCause::misc(span, hir_id); - match infcx.at(&misc_cause, param_env).eq(opaque_ty, hidden_ty) { - Ok(infer_ok) => ocx.register_infer_ok_obligations(infer_ok), + match ocx.eq(&misc_cause, param_env, opaque_ty, hidden_ty) { + Ok(()) => {} Err(ty_err) => { tcx.sess.delay_span_bug( span, @@ -463,15 +454,14 @@ fn check_opaque_meets_bounds<'tcx>( // Additionally require the hidden type to be well-formed with only the generics of the opaque type. // Defining use functions may have more bounds than the opaque type, which is ok, as long as the // hidden type is well formed even without those bounds. - let predicate = - ty::Binder::dummy(ty::PredicateKind::WellFormed(hidden_ty.into())).to_predicate(tcx); - ocx.register_obligation(Obligation::new(misc_cause, param_env, predicate)); + let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(hidden_ty.into())); + ocx.register_obligation(Obligation::new(tcx, misc_cause, param_env, predicate)); // Check that all obligations are satisfied by the implementation's // version. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); } match origin { // Checked when type checking the function containing them. @@ -489,6 +479,36 @@ fn check_opaque_meets_bounds<'tcx>( let _ = infcx.inner.borrow_mut().opaque_type_storage.take_opaque_types(); } +fn is_enum_of_nonnullable_ptr<'tcx>( + tcx: TyCtxt<'tcx>, + adt_def: AdtDef<'tcx>, + substs: SubstsRef<'tcx>, +) -> bool { + if adt_def.repr().inhibit_enum_layout_opt() { + return false; + } + + let [var_one, var_two] = &adt_def.variants().raw[..] else { + return false; + }; + let (([], [field]) | ([field], [])) = (&var_one.fields[..], &var_two.fields[..]) else { + return false; + }; + matches!(field.ty(tcx, substs).kind(), ty::FnPtr(..) | ty::Ref(..)) +} + +fn check_static_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) { + if tcx.codegen_fn_attrs(def_id).import_linkage.is_some() { + if match tcx.type_of(def_id).kind() { + ty::RawPtr(_) => false, + ty::Adt(adt_def, substs) => !is_enum_of_nonnullable_ptr(tcx, *adt_def, *substs), + _ => true, + } { + tcx.sess.emit_err(LinkageType { span: tcx.def_span(def_id) }); + } + } +} + fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { debug!( "check_item_type(it.def_id={:?}, it.name={})", @@ -501,16 +521,13 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { tcx.ensure().typeck(id.owner_id.def_id); maybe_check_static_with_link_section(tcx, id.owner_id.def_id); check_static_inhabited(tcx, id.owner_id.def_id); + check_static_linkage(tcx, id.owner_id.def_id); } DefKind::Const => { tcx.ensure().typeck(id.owner_id.def_id); } DefKind::Enum => { - let item = tcx.hir().item(id); - let hir::ItemKind::Enum(ref enum_definition, _) = item.kind else { - return; - }; - check_enum(tcx, &enum_definition.variants, item.owner_id.def_id); + check_enum(tcx, id.owner_id.def_id); } DefKind::Fn => {} // entirely within check_item_body DefKind::Impl => { @@ -642,6 +659,7 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { } hir::ForeignItemKind::Static(..) => { check_static_inhabited(tcx, def_id); + check_static_linkage(tcx, def_id); } _ => {} } @@ -659,7 +677,7 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) { pub(super) fn check_on_unimplemented(tcx: TyCtxt<'_>, item: &hir::Item<'_>) { // an error would be reported if this fails. - let _ = traits::OnUnimplementedDirective::of_item(tcx, item.owner_id.to_def_id()); + let _ = OnUnimplementedDirective::of_item(tcx, item.owner_id.to_def_id()); } pub(super) fn check_specialization_validity<'tcx>( @@ -1026,7 +1044,7 @@ pub(super) fn check_packed_inner( None } -pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtDef<'tcx>) { +pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) { if !adt.repr().transparent() { return; } @@ -1035,14 +1053,14 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD feature_err( &tcx.sess.parse_sess, sym::transparent_unions, - sp, + tcx.def_span(adt.did()), "transparent unions are unstable", ) .emit(); } if adt.variants().len() != 1 { - bad_variant_count(tcx, adt, sp, adt.did()); + bad_variant_count(tcx, adt, tcx.def_span(adt.did()), adt.did()); if adt.variants().is_empty() { // Don't bother checking the fields. No variants (and thus no fields) exist. return; @@ -1103,7 +1121,7 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD .filter_map(|(span, zst, _align1, _non_exhaustive)| if !zst { Some(span) } else { None }); let non_zst_count = non_zst_fields.clone().count(); if non_zst_count >= 2 { - bad_non_zero_sized_fields(tcx, adt, non_zst_count, non_zst_fields, sp); + bad_non_zero_sized_fields(tcx, adt, non_zst_count, non_zst_fields, tcx.def_span(adt.did())); } let incompatible_zst_fields = field_infos.clone().filter(|(_, _, _, opt)| opt.is_some()).count(); @@ -1143,12 +1161,11 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD } #[allow(trivial_numeric_casts)] -fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: LocalDefId) { +fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) { let def = tcx.adt_def(def_id); - let sp = tcx.def_span(def_id); def.destructor(tcx); // force the destructor to be evaluated - if vs.is_empty() { + if def.variants().is_empty() { if let Some(attr) = tcx.get_attrs(def_id.to_def_id(), sym::repr).next() { struct_span_err!( tcx.sess, @@ -1156,7 +1173,7 @@ fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: L E0084, "unsupported representation for zero-variant enum" ) - .span_label(sp, "zero-variant enum") + .span_label(tcx.def_span(def_id), "zero-variant enum") .emit(); } } @@ -1167,88 +1184,96 @@ fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: L feature_err( &tcx.sess.parse_sess, sym::repr128, - sp, + tcx.def_span(def_id), "repr with 128-bit type is unstable", ) .emit(); } } - for v in vs { - if let Some(ref e) = v.disr_expr { - tcx.ensure().typeck(tcx.hir().local_def_id(e.hir_id)); + for v in def.variants() { + if let ty::VariantDiscr::Explicit(discr_def_id) = v.discr { + tcx.ensure().typeck(discr_def_id.expect_local()); } } - if tcx.adt_def(def_id).repr().int.is_none() { - let is_unit = |var: &hir::Variant<'_>| matches!(var.data, hir::VariantData::Unit(..)); + if def.repr().int.is_none() { + let is_unit = |var: &ty::VariantDef| matches!(var.ctor_kind(), Some(CtorKind::Const)); + let has_disr = |var: &ty::VariantDef| matches!(var.discr, ty::VariantDiscr::Explicit(_)); - let has_disr = |var: &hir::Variant<'_>| var.disr_expr.is_some(); - let has_non_units = vs.iter().any(|var| !is_unit(var)); - let disr_units = vs.iter().any(|var| is_unit(&var) && has_disr(&var)); - let disr_non_unit = vs.iter().any(|var| !is_unit(&var) && has_disr(&var)); + let has_non_units = def.variants().iter().any(|var| !is_unit(var)); + let disr_units = def.variants().iter().any(|var| is_unit(&var) && has_disr(&var)); + let disr_non_unit = def.variants().iter().any(|var| !is_unit(&var) && has_disr(&var)); if disr_non_unit || (disr_units && has_non_units) { - let mut err = - struct_span_err!(tcx.sess, sp, E0732, "`#[repr(inttype)]` must be specified"); + let mut err = struct_span_err!( + tcx.sess, + tcx.def_span(def_id), + E0732, + "`#[repr(inttype)]` must be specified" + ); err.emit(); } } - detect_discriminant_duplicate(tcx, def.discriminants(tcx).collect(), vs, sp); - - check_transparent(tcx, sp, def); + detect_discriminant_duplicate(tcx, def); + check_transparent(tcx, def); } /// Part of enum check. Given the discriminants of an enum, errors if two or more discriminants are equal -fn detect_discriminant_duplicate<'tcx>( - tcx: TyCtxt<'tcx>, - mut discrs: Vec<(VariantIdx, Discr<'tcx>)>, - vs: &'tcx [hir::Variant<'tcx>], - self_span: Span, -) { +fn detect_discriminant_duplicate<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) { // Helper closure to reduce duplicate code. This gets called everytime we detect a duplicate. // Here `idx` refers to the order of which the discriminant appears, and its index in `vs` - let report = |dis: Discr<'tcx>, idx: usize, err: &mut Diagnostic| { - let var = &vs[idx]; // HIR for the duplicate discriminant - let (span, display_discr) = match var.disr_expr { - Some(ref expr) => { + let report = |dis: Discr<'tcx>, idx, err: &mut Diagnostic| { + let var = adt.variant(idx); // HIR for the duplicate discriminant + let (span, display_discr) = match var.discr { + ty::VariantDiscr::Explicit(discr_def_id) => { // In the case the discriminant is both a duplicate and overflowed, let the user know - if let hir::ExprKind::Lit(lit) = &tcx.hir().body(expr.body).value.kind + if let hir::Node::AnonConst(expr) = tcx.hir().get_by_def_id(discr_def_id.expect_local()) + && let hir::ExprKind::Lit(lit) = &tcx.hir().body(expr.body).value.kind && let rustc_ast::LitKind::Int(lit_value, _int_kind) = &lit.node && *lit_value != dis.val { - (tcx.hir().span(expr.hir_id), format!("`{dis}` (overflowed from `{lit_value}`)")) - // Otherwise, format the value as-is + (tcx.def_span(discr_def_id), format!("`{dis}` (overflowed from `{lit_value}`)")) } else { - (tcx.hir().span(expr.hir_id), format!("`{dis}`")) + // Otherwise, format the value as-is + (tcx.def_span(discr_def_id), format!("`{dis}`")) } } - None => { + // This should not happen. + ty::VariantDiscr::Relative(0) => (tcx.def_span(var.def_id), format!("`{dis}`")), + ty::VariantDiscr::Relative(distance_to_explicit) => { // At this point we know this discriminant is a duplicate, and was not explicitly // assigned by the user. Here we iterate backwards to fetch the HIR for the last // explicitly assigned discriminant, and letting the user know that this was the // increment startpoint, and how many steps from there leading to the duplicate - if let Some((n, hir::Variant { span, ident, .. })) = - vs[..idx].iter().rev().enumerate().find(|v| v.1.disr_expr.is_some()) + if let Some(explicit_idx) = + idx.as_u32().checked_sub(distance_to_explicit).map(VariantIdx::from_u32) { - let ve_ident = var.ident; - let n = n + 1; - let sp = if n > 1 { "variants" } else { "variant" }; + let explicit_variant = adt.variant(explicit_idx); + let ve_ident = var.name; + let ex_ident = explicit_variant.name; + let sp = if distance_to_explicit > 1 { "variants" } else { "variant" }; err.span_label( - *span, - format!("discriminant for `{ve_ident}` incremented from this startpoint (`{ident}` + {n} {sp} later => `{ve_ident}` = {dis})"), + tcx.def_span(explicit_variant.def_id), + format!( + "discriminant for `{ve_ident}` incremented from this startpoint \ + (`{ex_ident}` + {distance_to_explicit} {sp} later \ + => `{ve_ident}` = {dis})" + ), ); } - (vs[idx].span, format!("`{dis}`")) + (tcx.def_span(var.def_id), format!("`{dis}`")) } }; err.span_label(span, format!("{display_discr} assigned here")); }; + let mut discrs = adt.discriminants(tcx).collect::<Vec<_>>(); + // Here we loop through the discriminants, comparing each discriminant to another. // When a duplicate is detected, we instantiate an error and point to both // initial and duplicate value. The duplicate discriminant is then discarded by swapping @@ -1257,29 +1282,29 @@ fn detect_discriminant_duplicate<'tcx>( // style as we are mutating `discrs` on the fly). let mut i = 0; while i < discrs.len() { - let hir_var_i_idx = discrs[i].0.index(); + let var_i_idx = discrs[i].0; let mut error: Option<DiagnosticBuilder<'_, _>> = None; let mut o = i + 1; while o < discrs.len() { - let hir_var_o_idx = discrs[o].0.index(); + let var_o_idx = discrs[o].0; if discrs[i].1.val == discrs[o].1.val { let err = error.get_or_insert_with(|| { let mut ret = struct_span_err!( tcx.sess, - self_span, + tcx.def_span(adt.did()), E0081, "discriminant value `{}` assigned more than once", discrs[i].1, ); - report(discrs[i].1, hir_var_i_idx, &mut ret); + report(discrs[i].1, var_i_idx, &mut ret); ret }); - report(discrs[o].1, hir_var_o_idx, err); + report(discrs[o].1, var_o_idx, err); // Safe to unwrap here, as we wouldn't reach this point if `discrs` was empty discrs[o] = *discrs.last().unwrap(); diff --git a/compiler/rustc_hir_analysis/src/check/compare_method.rs b/compiler/rustc_hir_analysis/src/check/compare_method.rs index 32f66b06f..db150ebf0 100644 --- a/compiler/rustc_hir_analysis/src/check/compare_method.rs +++ b/compiler/rustc_hir_analysis/src/check/compare_method.rs @@ -1,7 +1,7 @@ use super::potentially_plural_count; use crate::errors::LifetimesOrBoundsMismatchOnTrait; use hir::def_id::{DefId, LocalDefId}; -use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::fx::{FxHashMap, FxIndexSet}; use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticId, ErrorGuaranteed}; use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; @@ -9,13 +9,12 @@ use rustc_hir::intravisit; use rustc_hir::{GenericParamKind, ImplItemKind, TraitItemKind}; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind}; -use rustc_infer::infer::{self, TyCtxtInferExt}; +use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt}; use rustc_infer::traits::util; use rustc_middle::ty::error::{ExpectedFound, TypeError}; use rustc_middle::ty::util::ExplicitSelf; -use rustc_middle::ty::InternalSubsts; use rustc_middle::ty::{ - self, AssocItem, DefIdTree, Ty, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitable, + self, DefIdTree, InternalSubsts, Ty, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitable, }; use rustc_middle::ty::{GenericParamDefKind, ToPredicate, TyCtxt}; use rustc_span::Span; @@ -50,11 +49,11 @@ pub(crate) fn compare_impl_method<'tcx>( return; } - if let Err(_) = compare_number_of_generics(tcx, impl_m, impl_m_span, trait_m, trait_item_span) { + if let Err(_) = compare_number_of_generics(tcx, impl_m, trait_m, trait_item_span, false) { return; } - if let Err(_) = compare_generic_param_kinds(tcx, impl_m, trait_m) { + if let Err(_) = compare_generic_param_kinds(tcx, impl_m, trait_m, false) { return; } @@ -68,8 +67,14 @@ pub(crate) fn compare_impl_method<'tcx>( return; } - if let Err(_) = compare_predicate_entailment(tcx, impl_m, impl_m_span, trait_m, impl_trait_ref) - { + if let Err(_) = compare_predicate_entailment( + tcx, + impl_m, + impl_m_span, + trait_m, + impl_trait_ref, + CheckImpliedWfMode::Check, + ) { return; } } @@ -143,10 +148,11 @@ pub(crate) fn compare_impl_method<'tcx>( #[instrument(level = "debug", skip(tcx, impl_m_span, impl_trait_ref))] fn compare_predicate_entailment<'tcx>( tcx: TyCtxt<'tcx>, - impl_m: &AssocItem, + impl_m: &ty::AssocItem, impl_m_span: Span, - trait_m: &AssocItem, + trait_m: &ty::AssocItem, impl_trait_ref: ty::TraitRef<'tcx>, + check_implied_wf: CheckImpliedWfMode, ) -> Result<(), ErrorGuaranteed> { let trait_to_impl_substs = impl_trait_ref.substs; @@ -156,8 +162,7 @@ fn compare_predicate_entailment<'tcx>( // FIXME(@lcnr): remove that after removing `cause.body_id` from // obligations. let impl_m_hir_id = tcx.hir().local_def_id_to_hir_id(impl_m.def_id.expect_local()); - // We sometimes modify the span further down. - let mut cause = ObligationCause::new( + let cause = ObligationCause::new( impl_m_span, impl_m_hir_id, ObligationCauseCode::CompareImplItemObligation { @@ -175,13 +180,11 @@ fn compare_predicate_entailment<'tcx>( impl_to_placeholder_substs.rebase_onto(tcx, impl_m.container_id(tcx), trait_to_impl_substs); debug!("compare_impl_method: trait_to_placeholder_substs={:?}", trait_to_placeholder_substs); - let impl_m_generics = tcx.generics_of(impl_m.def_id); - let trait_m_generics = tcx.generics_of(trait_m.def_id); let impl_m_predicates = tcx.predicates_of(impl_m.def_id); let trait_m_predicates = tcx.predicates_of(trait_m.def_id); // Check region bounds. - check_region_bounds_on_impl_item(tcx, impl_m, trait_m, &trait_m_generics, &impl_m_generics)?; + check_region_bounds_on_impl_item(tcx, impl_m, trait_m, false)?; // Create obligations for each predicate declared by the impl // definition in the context of the trait's parameter @@ -220,14 +223,11 @@ fn compare_predicate_entailment<'tcx>( debug!("compare_impl_method: caller_bounds={:?}", param_env.caller_bounds()); - let mut selcx = traits::SelectionContext::new(&infcx); let impl_m_own_bounds = impl_m_predicates.instantiate_own(tcx, impl_to_placeholder_substs); for (predicate, span) in iter::zip(impl_m_own_bounds.predicates, impl_m_own_bounds.spans) { let normalize_cause = traits::ObligationCause::misc(span, impl_m_hir_id); - let traits::Normalized { value: predicate, obligations } = - traits::normalize(&mut selcx, param_env, normalize_cause, predicate); + let predicate = ocx.normalize(&normalize_cause, param_env, predicate); - ocx.register_obligations(obligations); let cause = ObligationCause::new( span, impl_m_hir_id, @@ -237,7 +237,7 @@ fn compare_predicate_entailment<'tcx>( kind: impl_m.kind, }, ); - ocx.register_obligation(traits::Obligation::new(cause, param_env, predicate)); + ocx.register_obligation(traits::Obligation::new(tcx, cause, param_env, predicate)); } // We now need to check that the signature of the impl method is @@ -256,17 +256,17 @@ fn compare_predicate_entailment<'tcx>( // Compute placeholder form of impl and trait method tys. let tcx = infcx.tcx; - let mut wf_tys = FxHashSet::default(); + let mut wf_tys = FxIndexSet::default(); - let impl_sig = infcx.replace_bound_vars_with_fresh_vars( + let unnormalized_impl_sig = infcx.replace_bound_vars_with_fresh_vars( impl_m_span, infer::HigherRankedType, tcx.fn_sig(impl_m.def_id), ); + let unnormalized_impl_fty = tcx.mk_fn_ptr(ty::Binder::dummy(unnormalized_impl_sig)); let norm_cause = ObligationCause::misc(impl_m_span, impl_m_hir_id); - let impl_sig = ocx.normalize(norm_cause.clone(), param_env, impl_sig); - let impl_fty = tcx.mk_fn_ptr(ty::Binder::dummy(impl_sig)); + let impl_fty = ocx.normalize(&norm_cause, param_env, unnormalized_impl_fty); debug!("compare_impl_method: impl_fty={:?}", impl_fty); let trait_sig = tcx.bound_fn_sig(trait_m.def_id).subst(tcx, trait_to_placeholder_substs); @@ -276,7 +276,7 @@ fn compare_predicate_entailment<'tcx>( // we have to do this before normalization, since the normalized ty may // not contain the input parameters. See issue #87748. wf_tys.extend(trait_sig.inputs_and_output.iter()); - let trait_sig = ocx.normalize(norm_cause, param_env, trait_sig); + let trait_sig = ocx.normalize(&norm_cause, param_env, trait_sig); // We also have to add the normalized trait signature // as we don't normalize during implied bounds computation. wf_tys.extend(trait_sig.inputs_and_output.iter()); @@ -290,147 +290,126 @@ fn compare_predicate_entailment<'tcx>( // type would be more appropriate. In other places we have a `Vec<Span>` // corresponding to their `Vec<Predicate>`, but we don't have that here. // Fixing this would improve the output of test `issue-83765.rs`. - let mut result = infcx - .at(&cause, param_env) - .sup(trait_fty, impl_fty) - .map(|infer_ok| ocx.register_infer_ok_obligations(infer_ok)); - - // HACK(RPITIT): #101614. When we are trying to infer the hidden types for - // RPITITs, we need to equate the output tys instead of just subtyping. If - // we just use `sup` above, we'll end up `&'static str <: _#1t`, which causes - // us to infer `_#1t = #'_#2r str`, where `'_#2r` is unconstrained, which gets - // fixed up to `ReEmpty`, and which is certainly not what we want. - if trait_fty.has_infer_types() { - result = result.and_then(|()| { - infcx - .at(&cause, param_env) - .eq(trait_sig.output(), impl_sig.output()) - .map(|infer_ok| ocx.register_infer_ok_obligations(infer_ok)) - }); - } + let result = ocx.sup(&cause, param_env, trait_fty, impl_fty); if let Err(terr) = result { - debug!("sub_types failed: impl ty {:?}, trait ty {:?}", impl_fty, trait_fty); - - let (impl_err_span, trait_err_span) = - extract_spans_for_error_reporting(&infcx, terr, &cause, impl_m, trait_m); - - cause.span = impl_err_span; - - let mut diag = struct_span_err!( - tcx.sess, - cause.span(), - E0053, - "method `{}` has an incompatible type for trait", - trait_m.name - ); - match &terr { - TypeError::ArgumentMutability(0) | TypeError::ArgumentSorts(_, 0) - if trait_m.fn_has_self_parameter => - { - let ty = trait_sig.inputs()[0]; - let sugg = match ExplicitSelf::determine(ty, |_| ty == impl_trait_ref.self_ty()) { - ExplicitSelf::ByValue => "self".to_owned(), - ExplicitSelf::ByReference(_, hir::Mutability::Not) => "&self".to_owned(), - ExplicitSelf::ByReference(_, hir::Mutability::Mut) => "&mut self".to_owned(), - _ => format!("self: {ty}"), - }; - - // When the `impl` receiver is an arbitrary self type, like `self: Box<Self>`, the - // span points only at the type `Box<Self`>, but we want to cover the whole - // argument pattern and type. - let span = match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind { - ImplItemKind::Fn(ref sig, body) => tcx - .hir() - .body_param_names(body) - .zip(sig.decl.inputs.iter()) - .map(|(param, ty)| param.span.to(ty.span)) - .next() - .unwrap_or(impl_err_span), - _ => bug!("{:?} is not a method", impl_m), - }; - - diag.span_suggestion( - span, - "change the self-receiver type to match the trait", - sugg, - Applicability::MachineApplicable, - ); - } - TypeError::ArgumentMutability(i) | TypeError::ArgumentSorts(_, i) => { - if trait_sig.inputs().len() == *i { - // Suggestion to change output type. We do not suggest in `async` functions - // to avoid complex logic or incorrect output. - match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind { - ImplItemKind::Fn(ref sig, _) - if sig.header.asyncness == hir::IsAsync::NotAsync => - { - let msg = "change the output type to match the trait"; - let ap = Applicability::MachineApplicable; - match sig.decl.output { - hir::FnRetTy::DefaultReturn(sp) => { - let sugg = format!("-> {} ", trait_sig.output()); - diag.span_suggestion_verbose(sp, msg, sugg, ap); - } - hir::FnRetTy::Return(hir_ty) => { - let sugg = trait_sig.output(); - diag.span_suggestion(hir_ty.span, msg, sugg, ap); - } - }; - } - _ => {} - }; - } else if let Some(trait_ty) = trait_sig.inputs().get(*i) { - diag.span_suggestion( - impl_err_span, - "change the parameter type to match the trait", - trait_ty, - Applicability::MachineApplicable, - ); - } - } - _ => {} - } + debug!(?terr, "sub_types failed: impl ty {:?}, trait ty {:?}", impl_fty, trait_fty); - infcx.err_ctxt().note_type_err( - &mut diag, - &cause, - trait_err_span.map(|sp| (sp, "type in trait".to_owned())), - Some(infer::ValuePairs::Terms(ExpectedFound { - expected: trait_fty.into(), - found: impl_fty.into(), - })), + let emitted = report_trait_method_mismatch( + &infcx, + cause, terr, - false, - false, + (trait_m, trait_fty), + (impl_m, impl_fty), + trait_sig, + impl_trait_ref, ); + return Err(emitted); + } - return Err(diag.emit()); + if check_implied_wf == CheckImpliedWfMode::Check { + // We need to check that the impl's args are well-formed given + // the hybrid param-env (impl + trait method where-clauses). + ocx.register_obligation(traits::Obligation::new( + infcx.tcx, + ObligationCause::dummy(), + param_env, + ty::Binder::dummy(ty::PredicateKind::WellFormed(unnormalized_impl_fty.into())), + )); } + let emit_implied_wf_lint = || { + infcx.tcx.struct_span_lint_hir( + rustc_session::lint::builtin::IMPLIED_BOUNDS_ENTAILMENT, + impl_m_hir_id, + infcx.tcx.def_span(impl_m.def_id), + "impl method assumes more implied bounds than the corresponding trait method", + |lint| lint, + ); + }; // Check that all obligations are satisfied by the implementation's // version. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); - return Err(reported); + match check_implied_wf { + CheckImpliedWfMode::Check => { + return compare_predicate_entailment( + tcx, + impl_m, + impl_m_span, + trait_m, + impl_trait_ref, + CheckImpliedWfMode::Skip, + ) + .map(|()| { + // If the skip-mode was successful, emit a lint. + emit_implied_wf_lint(); + }); + } + CheckImpliedWfMode::Skip => { + let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None); + return Err(reported); + } + } } // Finally, resolve all regions. This catches wily misuses of // lifetime parameters. - let outlives_environment = OutlivesEnvironment::with_bounds( + let outlives_env = OutlivesEnvironment::with_bounds( param_env, Some(infcx), - infcx.implied_bounds_tys(param_env, impl_m_hir_id, wf_tys), + infcx.implied_bounds_tys(param_env, impl_m_hir_id, wf_tys.clone()), ); - infcx.check_region_obligations_and_report_errors( - impl_m.def_id.expect_local(), - &outlives_environment, + infcx.process_registered_region_obligations( + outlives_env.region_bound_pairs(), + outlives_env.param_env, ); + let errors = infcx.resolve_regions(&outlives_env); + if !errors.is_empty() { + // FIXME(compiler-errors): This can be simplified when IMPLIED_BOUNDS_ENTAILMENT + // becomes a hard error (i.e. ideally we'd just call `resolve_regions_and_report_errors` + match check_implied_wf { + CheckImpliedWfMode::Check => { + return compare_predicate_entailment( + tcx, + impl_m, + impl_m_span, + trait_m, + impl_trait_ref, + CheckImpliedWfMode::Skip, + ) + .map(|()| { + // If the skip-mode was successful, emit a lint. + emit_implied_wf_lint(); + }); + } + CheckImpliedWfMode::Skip => { + if infcx.tainted_by_errors().is_none() { + infcx.err_ctxt().report_region_errors(impl_m.def_id.expect_local(), &errors); + } + return Err(tcx + .sess + .delay_span_bug(rustc_span::DUMMY_SP, "error should have been emitted")); + } + } + } Ok(()) } +#[derive(Debug, PartialEq, Eq)] +enum CheckImpliedWfMode { + /// Checks implied well-formedness of the impl method. If it fails, we will + /// re-check with `Skip`, and emit a lint if it succeeds. + Check, + /// Skips checking implied well-formedness of the impl method, but will emit + /// a lint if the `compare_predicate_entailment` succeeded. This means that + /// the reason that we had failed earlier during `Check` was due to the impl + /// having stronger requirements than the trait. + Skip, +} + +#[instrument(skip(tcx), level = "debug", ret)] pub fn collect_trait_impl_trait_tys<'tcx>( tcx: TyCtxt<'tcx>, def_id: DefId, @@ -440,6 +419,11 @@ pub fn collect_trait_impl_trait_tys<'tcx>( let impl_trait_ref = tcx.impl_trait_ref(impl_m.impl_container(tcx).unwrap()).unwrap(); let param_env = tcx.param_env(def_id); + // First, check a few of the same thing as `compare_impl_method`, just so we don't ICE during substitutions later. + compare_number_of_generics(tcx, impl_m, trait_m, tcx.hir().span_if_local(impl_m.def_id), true)?; + compare_generic_param_kinds(tcx, impl_m, trait_m, true)?; + check_region_bounds_on_impl_item(tcx, impl_m, trait_m, true)?; + let trait_to_impl_substs = impl_trait_ref.substs; let impl_m_hir_id = tcx.hir().local_def_id_to_hir_id(impl_m.def_id.expect_local()); @@ -464,9 +448,10 @@ pub fn collect_trait_impl_trait_tys<'tcx>( let infcx = &tcx.infer_ctxt().build(); let ocx = ObligationCtxt::new(infcx); + // Normalize the impl signature with fresh variables for lifetime inference. let norm_cause = ObligationCause::misc(return_span, impl_m_hir_id); let impl_sig = ocx.normalize( - norm_cause.clone(), + &norm_cause, param_env, infcx.replace_bound_vars_with_fresh_vars( return_span, @@ -476,6 +461,10 @@ pub fn collect_trait_impl_trait_tys<'tcx>( ); let impl_return_ty = impl_sig.output(); + // Normalize the trait signature with liberated bound vars, passing it through + // the ImplTraitInTraitCollector, which gathers all of the RPITITs and replaces + // them with inference variables. + // We will use these inference variables to collect the hidden types of RPITITs. let mut collector = ImplTraitInTraitCollector::new(&ocx, return_span, param_env, impl_m_hir_id); let unnormalized_trait_sig = tcx .liberate_late_bound_regions( @@ -483,17 +472,15 @@ pub fn collect_trait_impl_trait_tys<'tcx>( tcx.bound_fn_sig(trait_m.def_id).subst(tcx, trait_to_placeholder_substs), ) .fold_with(&mut collector); - let trait_sig = ocx.normalize(norm_cause.clone(), param_env, unnormalized_trait_sig); + let trait_sig = ocx.normalize(&norm_cause, param_env, unnormalized_trait_sig); let trait_return_ty = trait_sig.output(); - let wf_tys = FxHashSet::from_iter( + let wf_tys = FxIndexSet::from_iter( unnormalized_trait_sig.inputs_and_output.iter().chain(trait_sig.inputs_and_output.iter()), ); - match infcx.at(&cause, param_env).eq(trait_return_ty, impl_return_ty) { - Ok(infer::InferOk { value: (), obligations }) => { - ocx.register_obligations(obligations); - } + match ocx.eq(&cause, param_env, trait_return_ty, impl_return_ty) { + Ok(()) => {} Err(terr) => { let mut diag = struct_span_err!( tcx.sess, @@ -521,23 +508,32 @@ pub fn collect_trait_impl_trait_tys<'tcx>( } } + debug!(?trait_sig, ?impl_sig, "equating function signatures"); + + let trait_fty = tcx.mk_fn_ptr(ty::Binder::dummy(trait_sig)); + let impl_fty = tcx.mk_fn_ptr(ty::Binder::dummy(impl_sig)); + // Unify the whole function signature. We need to do this to fully infer // the lifetimes of the return type, but do this after unifying just the // return types, since we want to avoid duplicating errors from // `compare_predicate_entailment`. - match infcx - .at(&cause, param_env) - .eq(tcx.mk_fn_ptr(ty::Binder::dummy(trait_sig)), tcx.mk_fn_ptr(ty::Binder::dummy(impl_sig))) - { - Ok(infer::InferOk { value: (), obligations }) => { - ocx.register_obligations(obligations); - } + match ocx.eq(&cause, param_env, trait_fty, impl_fty) { + Ok(()) => {} Err(terr) => { - let guar = tcx.sess.delay_span_bug( - return_span, - format!("could not unify `{trait_sig}` and `{impl_sig}`: {terr:?}"), + // This function gets called during `compare_predicate_entailment` when normalizing a + // signature that contains RPITIT. When the method signatures don't match, we have to + // emit an error now because `compare_predicate_entailment` will not report the error + // when normalization fails. + let emitted = report_trait_method_mismatch( + infcx, + cause, + terr, + (trait_m, trait_fty), + (impl_m, impl_fty), + trait_sig, + impl_trait_ref, ); - return Err(guar); + return Err(emitted); } } @@ -545,7 +541,7 @@ pub fn collect_trait_impl_trait_tys<'tcx>( // RPITs. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None); return Err(reported); } @@ -597,7 +593,13 @@ pub fn collect_trait_impl_trait_tys<'tcx>( let num_trait_substs = trait_to_impl_substs.len(); let num_impl_substs = tcx.generics_of(impl_m.container_id(tcx)).params.len(); let ty = tcx.fold_regions(ty, |region, _| { - let (ty::ReFree(_) | ty::ReEarlyBound(_)) = region.kind() else { return region; }; + match region.kind() { + // Remap all free regions, which correspond to late-bound regions in the function. + ty::ReFree(_) => {} + // Remap early-bound regions as long as they don't come from the `impl` itself. + ty::ReEarlyBound(ebr) if tcx.parent(ebr.def_id) != impl_m.container_id(tcx) => {} + _ => return region, + } let Some(ty::ReEarlyBound(e)) = map.get(®ion.into()).map(|r| r.expect_region().kind()) else { tcx @@ -618,11 +620,11 @@ pub fn collect_trait_impl_trait_tys<'tcx>( collected_tys.insert(def_id, ty); } Err(err) => { - tcx.sess.delay_span_bug( + let reported = tcx.sess.delay_span_bug( return_span, format!("could not fully resolve: {ty} => {err:?}"), ); - collected_tys.insert(def_id, tcx.ty_error()); + collected_tys.insert(def_id, tcx.ty_error_with_guaranteed(reported)); } } } @@ -675,12 +677,13 @@ impl<'tcx> TypeFolder<'tcx> for ImplTraitInTraitCollector<'_, 'tcx> { for (pred, pred_span) in self.tcx().bound_explicit_item_bounds(proj.item_def_id).subst_iter_copied(self.tcx(), proj.substs) { let pred = pred.fold_with(self); let pred = self.ocx.normalize( - ObligationCause::misc(self.span, self.body_id), + &ObligationCause::misc(self.span, self.body_id), self.param_env, pred, ); self.ocx.register_obligation(traits::Obligation::new( + self.tcx(), ObligationCause::new( self.span, self.body_id, @@ -697,16 +700,121 @@ impl<'tcx> TypeFolder<'tcx> for ImplTraitInTraitCollector<'_, 'tcx> { } } +fn report_trait_method_mismatch<'tcx>( + infcx: &InferCtxt<'tcx>, + mut cause: ObligationCause<'tcx>, + terr: TypeError<'tcx>, + (trait_m, trait_fty): (&ty::AssocItem, Ty<'tcx>), + (impl_m, impl_fty): (&ty::AssocItem, Ty<'tcx>), + trait_sig: ty::FnSig<'tcx>, + impl_trait_ref: ty::TraitRef<'tcx>, +) -> ErrorGuaranteed { + let tcx = infcx.tcx; + let (impl_err_span, trait_err_span) = + extract_spans_for_error_reporting(&infcx, terr, &cause, impl_m, trait_m); + + let mut diag = struct_span_err!( + tcx.sess, + impl_err_span, + E0053, + "method `{}` has an incompatible type for trait", + trait_m.name + ); + match &terr { + TypeError::ArgumentMutability(0) | TypeError::ArgumentSorts(_, 0) + if trait_m.fn_has_self_parameter => + { + let ty = trait_sig.inputs()[0]; + let sugg = match ExplicitSelf::determine(ty, |_| ty == impl_trait_ref.self_ty()) { + ExplicitSelf::ByValue => "self".to_owned(), + ExplicitSelf::ByReference(_, hir::Mutability::Not) => "&self".to_owned(), + ExplicitSelf::ByReference(_, hir::Mutability::Mut) => "&mut self".to_owned(), + _ => format!("self: {ty}"), + }; + + // When the `impl` receiver is an arbitrary self type, like `self: Box<Self>`, the + // span points only at the type `Box<Self`>, but we want to cover the whole + // argument pattern and type. + let span = match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind { + ImplItemKind::Fn(ref sig, body) => tcx + .hir() + .body_param_names(body) + .zip(sig.decl.inputs.iter()) + .map(|(param, ty)| param.span.to(ty.span)) + .next() + .unwrap_or(impl_err_span), + _ => bug!("{:?} is not a method", impl_m), + }; + + diag.span_suggestion( + span, + "change the self-receiver type to match the trait", + sugg, + Applicability::MachineApplicable, + ); + } + TypeError::ArgumentMutability(i) | TypeError::ArgumentSorts(_, i) => { + if trait_sig.inputs().len() == *i { + // Suggestion to change output type. We do not suggest in `async` functions + // to avoid complex logic or incorrect output. + match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind { + ImplItemKind::Fn(ref sig, _) if !sig.header.asyncness.is_async() => { + let msg = "change the output type to match the trait"; + let ap = Applicability::MachineApplicable; + match sig.decl.output { + hir::FnRetTy::DefaultReturn(sp) => { + let sugg = format!("-> {} ", trait_sig.output()); + diag.span_suggestion_verbose(sp, msg, sugg, ap); + } + hir::FnRetTy::Return(hir_ty) => { + let sugg = trait_sig.output(); + diag.span_suggestion(hir_ty.span, msg, sugg, ap); + } + }; + } + _ => {} + }; + } else if let Some(trait_ty) = trait_sig.inputs().get(*i) { + diag.span_suggestion( + impl_err_span, + "change the parameter type to match the trait", + trait_ty, + Applicability::MachineApplicable, + ); + } + } + _ => {} + } + + cause.span = impl_err_span; + infcx.err_ctxt().note_type_err( + &mut diag, + &cause, + trait_err_span.map(|sp| (sp, "type in trait".to_owned())), + Some(infer::ValuePairs::Terms(ExpectedFound { + expected: trait_fty.into(), + found: impl_fty.into(), + })), + terr, + false, + false, + ); + + return diag.emit(); +} + fn check_region_bounds_on_impl_item<'tcx>( tcx: TyCtxt<'tcx>, impl_m: &ty::AssocItem, trait_m: &ty::AssocItem, - trait_generics: &ty::Generics, - impl_generics: &ty::Generics, + delay: bool, ) -> Result<(), ErrorGuaranteed> { - let trait_params = trait_generics.own_counts().lifetimes; + let impl_generics = tcx.generics_of(impl_m.def_id); let impl_params = impl_generics.own_counts().lifetimes; + let trait_generics = tcx.generics_of(trait_m.def_id); + let trait_params = trait_generics.own_counts().lifetimes; + debug!( "check_region_bounds_on_impl_item: \ trait_generics={:?} \ @@ -729,23 +837,56 @@ fn check_region_bounds_on_impl_item<'tcx>( .get_generics(impl_m.def_id.expect_local()) .expect("expected impl item to have generics or else we can't compare them") .span; - let generics_span = if let Some(local_def_id) = trait_m.def_id.as_local() { - Some( - tcx.hir() - .get_generics(local_def_id) - .expect("expected trait item to have generics or else we can't compare them") - .span, - ) - } else { - None - }; - let reported = tcx.sess.emit_err(LifetimesOrBoundsMismatchOnTrait { - span, - item_kind: assoc_item_kind_str(impl_m), - ident: impl_m.ident(tcx), - generics_span, - }); + let mut generics_span = None; + let mut bounds_span = vec![]; + let mut where_span = None; + if let Some(trait_node) = tcx.hir().get_if_local(trait_m.def_id) + && let Some(trait_generics) = trait_node.generics() + { + generics_span = Some(trait_generics.span); + // FIXME: we could potentially look at the impl's bounds to not point at bounds that + // *are* present in the impl. + for p in trait_generics.predicates { + if let hir::WherePredicate::BoundPredicate(pred) = p { + for b in pred.bounds { + if let hir::GenericBound::Outlives(lt) = b { + bounds_span.push(lt.ident.span); + } + } + } + } + if let Some(impl_node) = tcx.hir().get_if_local(impl_m.def_id) + && let Some(impl_generics) = impl_node.generics() + { + let mut impl_bounds = 0; + for p in impl_generics.predicates { + if let hir::WherePredicate::BoundPredicate(pred) = p { + for b in pred.bounds { + if let hir::GenericBound::Outlives(_) = b { + impl_bounds += 1; + } + } + } + } + if impl_bounds == bounds_span.len() { + bounds_span = vec![]; + } else if impl_generics.has_where_clause_predicates { + where_span = Some(impl_generics.where_clause_span); + } + } + } + let reported = tcx + .sess + .create_err(LifetimesOrBoundsMismatchOnTrait { + span, + item_kind: assoc_item_kind_str(impl_m), + ident: impl_m.ident(tcx), + generics_span, + bounds_span, + where_span, + }) + .emit_unless(delay); return Err(reported); } @@ -891,9 +1032,9 @@ fn compare_self_type<'tcx>( fn compare_number_of_generics<'tcx>( tcx: TyCtxt<'tcx>, impl_: &ty::AssocItem, - _impl_span: Span, trait_: &ty::AssocItem, trait_span: Option<Span>, + delay: bool, ) -> Result<(), ErrorGuaranteed> { let trait_own_counts = tcx.generics_of(trait_.def_id).own_counts(); let impl_own_counts = tcx.generics_of(impl_.def_id).own_counts(); @@ -1023,7 +1164,7 @@ fn compare_number_of_generics<'tcx>( err.span_label(*span, "`impl Trait` introduces an implicit type parameter"); } - let reported = err.emit(); + let reported = err.emit_unless(delay); err_occurred = Some(reported); } } @@ -1275,6 +1416,7 @@ fn compare_generic_param_kinds<'tcx>( tcx: TyCtxt<'tcx>, impl_item: &ty::AssocItem, trait_item: &ty::AssocItem, + delay: bool, ) -> Result<(), ErrorGuaranteed> { assert_eq!(impl_item.kind, trait_item.kind); @@ -1332,7 +1474,7 @@ fn compare_generic_param_kinds<'tcx>( err.span_label(impl_header_span, ""); err.span_label(param_impl_span, make_param_message("found", param_impl)); - let reported = err.emit(); + let reported = err.emit_unless(delay); return Err(reported); } } @@ -1381,18 +1523,15 @@ pub(crate) fn raw_compare_const_impl<'tcx>( ); // There is no "body" here, so just pass dummy id. - let impl_ty = ocx.normalize(cause.clone(), param_env, impl_ty); + let impl_ty = ocx.normalize(&cause, param_env, impl_ty); debug!("compare_const_impl: impl_ty={:?}", impl_ty); - let trait_ty = ocx.normalize(cause.clone(), param_env, trait_ty); + let trait_ty = ocx.normalize(&cause, param_env, trait_ty); debug!("compare_const_impl: trait_ty={:?}", trait_ty); - let err = infcx - .at(&cause, param_env) - .sup(trait_ty, impl_ty) - .map(|ok| ocx.register_infer_ok_obligations(ok)); + let err = ocx.sup(&cause, param_env, trait_ty, impl_ty); if let Err(terr) = err { debug!( @@ -1441,7 +1580,7 @@ pub(crate) fn raw_compare_const_impl<'tcx>( // version. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - return Err(infcx.err_ctxt().report_fulfillment_errors(&errors, None, false)); + return Err(infcx.err_ctxt().report_fulfillment_errors(&errors, None)); } // FIXME return `ErrorReported` if region obligations error? @@ -1461,9 +1600,9 @@ pub(crate) fn compare_ty_impl<'tcx>( debug!("compare_impl_type(impl_trait_ref={:?})", impl_trait_ref); let _: Result<(), ErrorGuaranteed> = (|| { - compare_number_of_generics(tcx, impl_ty, impl_ty_span, trait_ty, trait_item_span)?; + compare_number_of_generics(tcx, impl_ty, trait_ty, trait_item_span, false)?; - compare_generic_param_kinds(tcx, impl_ty, trait_ty)?; + compare_generic_param_kinds(tcx, impl_ty, trait_ty, false)?; let sp = tcx.def_span(impl_ty.def_id); compare_type_predicate_entailment(tcx, impl_ty, sp, trait_ty, impl_trait_ref)?; @@ -1485,18 +1624,10 @@ fn compare_type_predicate_entailment<'tcx>( let trait_to_impl_substs = impl_substs.rebase_onto(tcx, impl_ty.container_id(tcx), impl_trait_ref.substs); - let impl_ty_generics = tcx.generics_of(impl_ty.def_id); - let trait_ty_generics = tcx.generics_of(trait_ty.def_id); let impl_ty_predicates = tcx.predicates_of(impl_ty.def_id); let trait_ty_predicates = tcx.predicates_of(trait_ty.def_id); - check_region_bounds_on_impl_item( - tcx, - impl_ty, - trait_ty, - &trait_ty_generics, - &impl_ty_generics, - )?; + check_region_bounds_on_impl_item(tcx, impl_ty, trait_ty, false)?; let impl_ty_own_bounds = impl_ty_predicates.instantiate_own(tcx, impl_substs); @@ -1533,14 +1664,11 @@ fn compare_type_predicate_entailment<'tcx>( debug!("compare_type_predicate_entailment: caller_bounds={:?}", param_env.caller_bounds()); - let mut selcx = traits::SelectionContext::new(&infcx); - assert_eq!(impl_ty_own_bounds.predicates.len(), impl_ty_own_bounds.spans.len()); for (span, predicate) in std::iter::zip(impl_ty_own_bounds.spans, impl_ty_own_bounds.predicates) { let cause = ObligationCause::misc(span, impl_ty_hir_id); - let traits::Normalized { value: predicate, obligations } = - traits::normalize(&mut selcx, param_env, cause, predicate); + let predicate = ocx.normalize(&cause, param_env, predicate); let cause = ObligationCause::new( span, @@ -1551,15 +1679,14 @@ fn compare_type_predicate_entailment<'tcx>( kind: impl_ty.kind, }, ); - ocx.register_obligations(obligations); - ocx.register_obligation(traits::Obligation::new(cause, param_env, predicate)); + ocx.register_obligation(traits::Obligation::new(tcx, cause, param_env, predicate)); } // Check that all obligations are satisfied by the implementation's // version. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None); return Err(reported); } @@ -1665,13 +1792,10 @@ pub fn check_type_bounds<'tcx>( GenericParamDefKind::Const { .. } => { let bound_var = ty::BoundVariableKind::Const; bound_vars.push(bound_var); - tcx.mk_const(ty::ConstS { - ty: tcx.type_of(param.def_id), - kind: ty::ConstKind::Bound( - ty::INNERMOST, - ty::BoundVar::from_usize(bound_vars.len() - 1), - ), - }) + tcx.mk_const( + ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from_usize(bound_vars.len() - 1)), + tcx.type_of(param.def_id), + ) .into() } }); @@ -1737,7 +1861,6 @@ pub fn check_type_bounds<'tcx>( let assumed_wf_types = ocx.assumed_wf_types(param_env, impl_ty_span, impl_ty.def_id.expect_local()); - let mut selcx = traits::SelectionContext::new(&infcx); let normalize_cause = ObligationCause::new( impl_ty_span, impl_ty_hir_id, @@ -1760,29 +1883,24 @@ pub fn check_type_bounds<'tcx>( .subst_iter_copied(tcx, rebased_substs) .map(|(concrete_ty_bound, span)| { debug!("check_type_bounds: concrete_ty_bound = {:?}", concrete_ty_bound); - traits::Obligation::new(mk_cause(span), param_env, concrete_ty_bound) + traits::Obligation::new(tcx, mk_cause(span), param_env, concrete_ty_bound) }) .collect(); debug!("check_type_bounds: item_bounds={:?}", obligations); for mut obligation in util::elaborate_obligations(tcx, obligations) { - let traits::Normalized { value: normalized_predicate, obligations } = traits::normalize( - &mut selcx, - normalize_param_env, - normalize_cause.clone(), - obligation.predicate, - ); + let normalized_predicate = + ocx.normalize(&normalize_cause, normalize_param_env, obligation.predicate); debug!("compare_projection_bounds: normalized predicate = {:?}", normalized_predicate); obligation.predicate = normalized_predicate; - ocx.register_obligations(obligations); ocx.register_obligation(obligation); } // Check that all obligations are satisfied by the implementation's // version. let errors = ocx.select_all_or_error(); if !errors.is_empty() { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None); return Err(reported); } diff --git a/compiler/rustc_hir_analysis/src/check/dropck.rs b/compiler/rustc_hir_analysis/src/check/dropck.rs index a74016e22..d6e3ddb0a 100644 --- a/compiler/rustc_hir_analysis/src/check/dropck.rs +++ b/compiler/rustc_hir_analysis/src/check/dropck.rs @@ -183,19 +183,27 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>( let predicate = predicate.kind(); let p = p.kind(); match (predicate.skip_binder(), p.skip_binder()) { - (ty::PredicateKind::Trait(a), ty::PredicateKind::Trait(b)) => { - relator.relate(predicate.rebind(a), p.rebind(b)).is_ok() - } - (ty::PredicateKind::Projection(a), ty::PredicateKind::Projection(b)) => { - relator.relate(predicate.rebind(a), p.rebind(b)).is_ok() - } + ( + ty::PredicateKind::Clause(ty::Clause::Trait(a)), + ty::PredicateKind::Clause(ty::Clause::Trait(b)), + ) => relator.relate(predicate.rebind(a), p.rebind(b)).is_ok(), + ( + ty::PredicateKind::Clause(ty::Clause::Projection(a)), + ty::PredicateKind::Clause(ty::Clause::Projection(b)), + ) => relator.relate(predicate.rebind(a), p.rebind(b)).is_ok(), ( ty::PredicateKind::ConstEvaluatable(a), ty::PredicateKind::ConstEvaluatable(b), ) => relator.relate(predicate.rebind(a), predicate.rebind(b)).is_ok(), ( - ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty_a, lt_a)), - ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty_b, lt_b)), + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(ty::OutlivesPredicate( + ty_a, + lt_a, + ))), + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(ty::OutlivesPredicate( + ty_b, + lt_b, + ))), ) => { relator.relate(predicate.rebind(ty_a), p.rebind(ty_b)).is_ok() && relator.relate(predicate.rebind(lt_a), p.rebind(lt_b)).is_ok() @@ -225,9 +233,10 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>( result } -// This is an implementation of the TypeRelation trait with the -// aim of simply comparing for equality (without side-effects). -// It is not intended to be used anywhere else other than here. +/// This is an implementation of the [`TypeRelation`] trait with the +/// aim of simply comparing for equality (without side-effects). +/// +/// It is not intended to be used anywhere else other than here. pub(crate) struct SimpleEqRelation<'tcx> { tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, @@ -244,6 +253,10 @@ impl<'tcx> TypeRelation<'tcx> for SimpleEqRelation<'tcx> { self.tcx } + fn intercrate(&self) -> bool { + false + } + fn param_env(&self) -> ty::ParamEnv<'tcx> { self.param_env } @@ -256,6 +269,10 @@ impl<'tcx> TypeRelation<'tcx> for SimpleEqRelation<'tcx> { true } + fn mark_ambiguous(&mut self) { + bug!() + } + fn relate_with_variance<T: Relate<'tcx>>( &mut self, _: ty::Variance, diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs index 609095c9c..69e54b41d 100644 --- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs +++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs @@ -134,15 +134,18 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) { let name_str = intrinsic_name.as_str(); let bound_vars = tcx.mk_bound_variable_kinds( - [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)] - .iter() - .copied(), + [ + ty::BoundVariableKind::Region(ty::BrAnon(0, None)), + ty::BoundVariableKind::Region(ty::BrEnv), + ] + .iter() + .copied(), ); let mk_va_list_ty = |mutbl| { tcx.lang_items().va_list().map(|did| { let region = tcx.mk_region(ty::ReLateBound( ty::INNERMOST, - ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) }, + ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) }, )); let env_region = tcx.mk_region(ty::ReLateBound( ty::INNERMOST, @@ -364,7 +367,8 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) { ); let discriminant_def_id = assoc_items[0]; - let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) }; + let br = + ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) }; ( 1, vec![ @@ -418,7 +422,8 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) { sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()), sym::raw_eq => { - let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) }; + let br = + ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) }; let param_ty = tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)); (1, vec![param_ty; 2], tcx.types.bool) diff --git a/compiler/rustc_hir_analysis/src/check/mod.rs b/compiler/rustc_hir_analysis/src/check/mod.rs index 2e7b10257..29255472a 100644 --- a/compiler/rustc_hir_analysis/src/check/mod.rs +++ b/compiler/rustc_hir_analysis/src/check/mod.rs @@ -159,7 +159,7 @@ fn maybe_check_static_with_link_section(tcx: TyCtxt<'_>, id: LocalDefId) { // the consumer's responsibility to ensure all bytes that have been read // have defined values. if let Ok(alloc) = tcx.eval_static_initializer(id.to_def_id()) - && alloc.inner().provenance().len() != 0 + && alloc.inner().provenance().ptrs().len() != 0 { let msg = "statics with a custom `#[link_section]` must be a \ simple list of bytes on the wasm target with no \ @@ -309,7 +309,7 @@ fn bounds_from_generic_predicates<'tcx>( debug!("predicate {:?}", predicate); let bound_predicate = predicate.kind(); match bound_predicate.skip_binder() { - ty::PredicateKind::Trait(trait_predicate) => { + ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) => { let entry = types.entry(trait_predicate.self_ty()).or_default(); let def_id = trait_predicate.def_id(); if Some(def_id) != tcx.lang_items().sized_trait() { @@ -318,7 +318,7 @@ fn bounds_from_generic_predicates<'tcx>( entry.push(trait_predicate.def_id()); } } - ty::PredicateKind::Projection(projection_pred) => { + ty::PredicateKind::Clause(ty::Clause::Projection(projection_pred)) => { projections.push(bound_predicate.rebind(projection_pred)); } _ => {} diff --git a/compiler/rustc_hir_analysis/src/check/region.rs b/compiler/rustc_hir_analysis/src/check/region.rs index ff32329e4..b315ebad4 100644 --- a/compiler/rustc_hir_analysis/src/check/region.rs +++ b/compiler/rustc_hir_analysis/src/check/region.rs @@ -241,17 +241,46 @@ fn resolve_expr<'tcx>(visitor: &mut RegionResolutionVisitor<'tcx>, expr: &'tcx h // scopes, meaning that temporaries cannot outlive them. // This ensures fixed size stacks. hir::ExprKind::Binary( - source_map::Spanned { node: hir::BinOpKind::And, .. }, - _, - ref r, - ) - | hir::ExprKind::Binary( - source_map::Spanned { node: hir::BinOpKind::Or, .. }, - _, + source_map::Spanned { node: hir::BinOpKind::And | hir::BinOpKind::Or, .. }, + ref l, ref r, ) => { - // For shortcircuiting operators, mark the RHS as a terminating - // scope since it only executes conditionally. + // expr is a short circuiting operator (|| or &&). As its + // functionality can't be overridden by traits, it always + // processes bool sub-expressions. bools are Copy and thus we + // can drop any temporaries in evaluation (read) order + // (with the exception of potentially failing let expressions). + // We achieve this by enclosing the operands in a terminating + // scope, both the LHS and the RHS. + + // We optimize this a little in the presence of chains. + // Chains like a && b && c get lowered to AND(AND(a, b), c). + // In here, b and c are RHS, while a is the only LHS operand in + // that chain. This holds true for longer chains as well: the + // leading operand is always the only LHS operand that is not a + // binop itself. Putting a binop like AND(a, b) into a + // terminating scope is not useful, thus we only put the LHS + // into a terminating scope if it is not a binop. + + let terminate_lhs = match l.kind { + // let expressions can create temporaries that live on + hir::ExprKind::Let(_) => false, + // binops already drop their temporaries, so there is no + // need to put them into a terminating scope. + // This is purely an optimization to reduce the number of + // terminating scopes. + hir::ExprKind::Binary( + source_map::Spanned { + node: hir::BinOpKind::And | hir::BinOpKind::Or, .. + }, + .., + ) => false, + // otherwise: mark it as terminating + _ => true, + }; + if terminate_lhs { + terminating(l.hir_id.local_id); + } // `Let` expressions (in a let-chain) shouldn't be terminating, as their temporaries // should live beyond the immediate expression diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs index a23575004..b065ace6b 100644 --- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs +++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs @@ -1,7 +1,7 @@ use crate::constrained_generic_params::{identify_constrained_generic_params, Parameter}; use hir::def::DefKind; use rustc_ast as ast; -use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet}; use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed}; use rustc_hir as hir; use rustc_hir::def_id::{DefId, LocalDefId}; @@ -14,13 +14,14 @@ use rustc_middle::mir::ConstraintCategory; use rustc_middle::ty::query::Providers; use rustc_middle::ty::trait_def::TraitSpecializationKind; use rustc_middle::ty::{ - self, AdtKind, DefIdTree, GenericParamDefKind, ToPredicate, Ty, TyCtxt, TypeFoldable, - TypeSuperVisitable, TypeVisitable, TypeVisitor, + self, AdtKind, DefIdTree, GenericParamDefKind, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, + TypeVisitable, TypeVisitor, }; use rustc_middle::ty::{GenericArgKind, InternalSubsts}; use rustc_session::parse::feature_err; use rustc_span::symbol::{sym, Ident, Symbol}; use rustc_span::{Span, DUMMY_SP}; +use rustc_target::spec::abi::Abi; use rustc_trait_selection::autoderef::Autoderef; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _; @@ -52,12 +53,14 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> { self.ocx.infcx.tcx } + // Convenience function to normalize during wfcheck. This performs + // `ObligationCtxt::normalize`, but provides a nice `ObligationCauseCode`. fn normalize<T>(&self, span: Span, loc: Option<WellFormedLoc>, value: T) -> T where T: TypeFoldable<'tcx>, { self.ocx.normalize( - ObligationCause::new(span, self.body_id, ObligationCauseCode::WellFormed(loc)), + &ObligationCause::new(span, self.body_id, ObligationCauseCode::WellFormed(loc)), self.param_env, value, ) @@ -74,9 +77,10 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> { // for a type to be WF, we do not need to check if const trait predicates satisfy. let param_env = self.param_env.without_const(); self.ocx.register_obligation(traits::Obligation::new( + self.tcx(), cause, param_env, - ty::Binder::dummy(ty::PredicateKind::WellFormed(arg)).to_predicate(self.tcx()), + ty::Binder::dummy(ty::PredicateKind::WellFormed(arg)), )); } } @@ -104,7 +108,7 @@ pub(super) fn enter_wf_checking_ctxt<'tcx, F>( f(&mut wfcx); let errors = wfcx.select_all_or_error(); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); return; } @@ -116,7 +120,7 @@ pub(super) fn enter_wf_checking_ctxt<'tcx, F>( } fn check_well_formed(tcx: TyCtxt<'_>, def_id: hir::OwnerId) { - let node = tcx.hir().expect_owner(def_id); + let node = tcx.hir().owner(def_id); match node { hir::OwnerNode::Crate(_) => {} hir::OwnerNode::Item(item) => check_item(tcx, item), @@ -218,19 +222,16 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) { hir::ItemKind::Const(ty, ..) => { check_item_type(tcx, def_id, ty.span, false); } - hir::ItemKind::Struct(ref struct_def, ref ast_generics) => { - check_type_defn(tcx, item, false, |wfcx| vec![wfcx.non_enum_variant(struct_def)]); - + hir::ItemKind::Struct(_, ref ast_generics) => { + check_type_defn(tcx, item, false); check_variances_for_type_defn(tcx, item, ast_generics); } - hir::ItemKind::Union(ref struct_def, ref ast_generics) => { - check_type_defn(tcx, item, true, |wfcx| vec![wfcx.non_enum_variant(struct_def)]); - + hir::ItemKind::Union(_, ref ast_generics) => { + check_type_defn(tcx, item, true); check_variances_for_type_defn(tcx, item, ast_generics); } - hir::ItemKind::Enum(ref enum_def, ref ast_generics) => { - check_type_defn(tcx, item, true, |wfcx| wfcx.enum_variants(enum_def)); - + hir::ItemKind::Enum(_, ref ast_generics) => { + check_type_defn(tcx, item, true); check_variances_for_type_defn(tcx, item, ast_generics); } hir::ItemKind::Trait(..) => { @@ -414,7 +415,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe .iter() .copied() .collect::<Vec<_>>(), - &FxHashSet::default(), + &FxIndexSet::default(), gat_def_id.def_id, gat_generics, ) @@ -463,12 +464,16 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe let mut unsatisfied_bounds: Vec<_> = required_bounds .into_iter() .filter(|clause| match clause.kind().skip_binder() { - ty::PredicateKind::RegionOutlives(ty::OutlivesPredicate(a, b)) => { - !region_known_to_outlive(tcx, gat_hir, param_env, &FxHashSet::default(), a, b) - } - ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(a, b)) => { - !ty_known_to_outlive(tcx, gat_hir, param_env, &FxHashSet::default(), a, b) + ty::PredicateKind::Clause(ty::Clause::RegionOutlives(ty::OutlivesPredicate( + a, + b, + ))) => { + !region_known_to_outlive(tcx, gat_hir, param_env, &FxIndexSet::default(), a, b) } + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(ty::OutlivesPredicate( + a, + b, + ))) => !ty_known_to_outlive(tcx, gat_hir, param_env, &FxIndexSet::default(), a, b), _ => bug!("Unexpected PredicateKind"), }) .map(|clause| clause.to_string()) @@ -549,7 +554,7 @@ fn gather_gat_bounds<'tcx, T: TypeFoldable<'tcx>>( param_env: ty::ParamEnv<'tcx>, item_hir: hir::HirId, to_check: T, - wf_tys: &FxHashSet<Ty<'tcx>>, + wf_tys: &FxIndexSet<Ty<'tcx>>, gat_def_id: LocalDefId, gat_generics: &'tcx ty::Generics, ) -> Option<FxHashSet<ty::Predicate<'tcx>>> { @@ -600,8 +605,9 @@ fn gather_gat_bounds<'tcx, T: TypeFoldable<'tcx>>( })); // The predicate we expect to see. (In our example, // `Self: 'me`.) - let clause = - ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty_param, region_param)); + let clause = ty::PredicateKind::Clause(ty::Clause::TypeOutlives( + ty::OutlivesPredicate(ty_param, region_param), + )); let clause = tcx.mk_predicate(ty::Binder::dummy(clause)); bounds.insert(clause); } @@ -637,9 +643,8 @@ fn gather_gat_bounds<'tcx, T: TypeFoldable<'tcx>>( name: region_b_param.name, })); // The predicate we expect to see. - let clause = ty::PredicateKind::RegionOutlives(ty::OutlivesPredicate( - region_a_param, - region_b_param, + let clause = ty::PredicateKind::Clause(ty::Clause::RegionOutlives( + ty::OutlivesPredicate(region_a_param, region_b_param), )); let clause = tcx.mk_predicate(ty::Binder::dummy(clause)); bounds.insert(clause); @@ -656,7 +661,7 @@ fn ty_known_to_outlive<'tcx>( tcx: TyCtxt<'tcx>, id: hir::HirId, param_env: ty::ParamEnv<'tcx>, - wf_tys: &FxHashSet<Ty<'tcx>>, + wf_tys: &FxIndexSet<Ty<'tcx>>, ty: Ty<'tcx>, region: ty::Region<'tcx>, ) -> bool { @@ -673,7 +678,7 @@ fn region_known_to_outlive<'tcx>( tcx: TyCtxt<'tcx>, id: hir::HirId, param_env: ty::ParamEnv<'tcx>, - wf_tys: &FxHashSet<Ty<'tcx>>, + wf_tys: &FxIndexSet<Ty<'tcx>>, region_a: ty::Region<'tcx>, region_b: ty::Region<'tcx>, ) -> bool { @@ -697,7 +702,7 @@ fn resolve_regions_with_wf_tys<'tcx>( tcx: TyCtxt<'tcx>, id: hir::HirId, param_env: ty::ParamEnv<'tcx>, - wf_tys: &FxHashSet<Ty<'tcx>>, + wf_tys: &FxIndexSet<Ty<'tcx>>, add_constraints: impl for<'a> FnOnce(&'a InferCtxt<'tcx>, &'a RegionBoundPairs<'tcx>), ) -> bool { // Unfortunately, we have to use a new `InferCtxt` each call, because @@ -855,7 +860,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) { // Const parameters are well formed if their type is structural match. hir::GenericParamKind::Const { ty: hir_ty, default: _ } => { - let ty = tcx.type_of(tcx.hir().local_def_id(param.hir_id)); + let ty = tcx.type_of(param.def_id); if tcx.features().adt_const_params { if let Some(non_structural_match_ty) = @@ -1037,27 +1042,25 @@ fn item_adt_kind(kind: &ItemKind<'_>) -> Option<AdtKind> { } /// In a type definition, we check that to ensure that the types of the fields are well-formed. -fn check_type_defn<'tcx, F>( - tcx: TyCtxt<'tcx>, - item: &hir::Item<'tcx>, - all_sized: bool, - mut lookup_fields: F, -) where - F: FnMut(&WfCheckingCtxt<'_, 'tcx>) -> Vec<AdtVariant<'tcx>>, -{ +fn check_type_defn<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item<'tcx>, all_sized: bool) { let _ = tcx.representability(item.owner_id.def_id); + let adt_def = tcx.adt_def(item.owner_id); enter_wf_checking_ctxt(tcx, item.span, item.owner_id.def_id, |wfcx| { - let variants = lookup_fields(wfcx); - let packed = tcx.adt_def(item.owner_id).repr().packed(); + let variants = adt_def.variants(); + let packed = adt_def.repr().packed(); - for variant in &variants { + for variant in variants.iter() { // All field types must be well-formed. for field in &variant.fields { + let field_id = field.did.expect_local(); + let hir::Node::Field(hir::FieldDef { ty: hir_ty, .. }) = tcx.hir().get_by_def_id(field_id) + else { bug!() }; + let ty = wfcx.normalize(hir_ty.span, None, tcx.type_of(field.did)); wfcx.register_wf_obligation( - field.span, - Some(WellFormedLoc::Ty(field.def_id)), - field.ty.into(), + hir_ty.span, + Some(WellFormedLoc::Ty(field_id)), + ty.into(), ) } @@ -1065,7 +1068,7 @@ fn check_type_defn<'tcx, F>( // intermediate types must be sized. let needs_drop_copy = || { packed && { - let ty = variant.fields.last().unwrap().ty; + let ty = tcx.type_of(variant.fields.last().unwrap().did); let ty = tcx.erase_regions(ty); if ty.needs_infer() { tcx.sess @@ -1084,39 +1087,43 @@ fn check_type_defn<'tcx, F>( variant.fields[..variant.fields.len() - unsized_len].iter().enumerate() { let last = idx == variant.fields.len() - 1; + let field_id = field.did.expect_local(); + let hir::Node::Field(hir::FieldDef { ty: hir_ty, .. }) = tcx.hir().get_by_def_id(field_id) + else { bug!() }; + let ty = wfcx.normalize(hir_ty.span, None, tcx.type_of(field.did)); wfcx.register_bound( traits::ObligationCause::new( - field.span, + hir_ty.span, wfcx.body_id, traits::FieldSized { adt_kind: match item_adt_kind(&item.kind) { Some(i) => i, None => bug!(), }, - span: field.span, + span: hir_ty.span, last, }, ), wfcx.param_env, - field.ty, + ty, tcx.require_lang_item(LangItem::Sized, None), ); } // Explicit `enum` discriminant values must const-evaluate successfully. - if let Some(discr_def_id) = variant.explicit_discr { + if let ty::VariantDiscr::Explicit(discr_def_id) = variant.discr { let cause = traits::ObligationCause::new( tcx.def_span(discr_def_id), wfcx.body_id, traits::MiscObligation, ); wfcx.register_obligation(traits::Obligation::new( + tcx, cause, wfcx.param_env, ty::Binder::dummy(ty::PredicateKind::ConstEvaluatable( - ty::Const::from_anon_const(tcx, discr_def_id), - )) - .to_predicate(tcx), + ty::Const::from_anon_const(tcx, discr_def_id.expect_local()), + )), )); } } @@ -1453,7 +1460,7 @@ fn check_where_clauses<'tcx>(wfcx: &WfCheckingCtxt<'_, 'tcx>, span: Span, def_id wfcx.body_id, traits::ItemObligation(def_id.to_def_id()), ); - traits::Obligation::new(cause, wfcx.param_env, pred) + traits::Obligation::new(tcx, cause, wfcx.param_env, pred) }); let predicates = predicates.0.instantiate_identity(tcx); @@ -1537,23 +1544,50 @@ fn check_fn_or_method<'tcx>( check_where_clauses(wfcx, span, def_id); check_return_position_impl_trait_in_trait_bounds( - tcx, wfcx, def_id, sig.output(), hir_decl.output.span(), ); + + if sig.abi == Abi::RustCall { + let span = tcx.def_span(def_id); + let has_implicit_self = hir_decl.implicit_self != hir::ImplicitSelfKind::None; + let mut inputs = sig.inputs().iter().skip(if has_implicit_self { 1 } else { 0 }); + // Check that the argument is a tuple + if let Some(ty) = inputs.next() { + wfcx.register_bound( + ObligationCause::new(span, wfcx.body_id, ObligationCauseCode::RustCall), + wfcx.param_env, + *ty, + tcx.require_lang_item(hir::LangItem::Tuple, Some(span)), + ); + } else { + tcx.sess.span_err( + hir_decl.inputs.last().map_or(span, |input| input.span), + "functions with the \"rust-call\" ABI must take a single non-self tuple argument", + ); + } + // No more inputs other than the `self` type and the tuple type + if inputs.next().is_some() { + tcx.sess.span_err( + hir_decl.inputs.last().map_or(span, |input| input.span), + "functions with the \"rust-call\" ABI must take a single non-self tuple argument", + ); + } + } } /// Basically `check_associated_type_bounds`, but separated for now and should be /// deduplicated when RPITITs get lowered into real associated items. +#[tracing::instrument(level = "trace", skip(wfcx))] fn check_return_position_impl_trait_in_trait_bounds<'tcx>( - tcx: TyCtxt<'tcx>, wfcx: &WfCheckingCtxt<'_, 'tcx>, fn_def_id: LocalDefId, fn_output: Ty<'tcx>, span: Span, ) { + let tcx = wfcx.tcx(); if let Some(assoc_item) = tcx.opt_associated_item(fn_def_id.to_def_id()) && assoc_item.container == ty::AssocItemContainer::TraitContainer { @@ -1563,8 +1597,10 @@ fn check_return_position_impl_trait_in_trait_bounds<'tcx>( && tcx.def_kind(proj.item_def_id) == DefKind::ImplTraitPlaceholder && tcx.impl_trait_in_trait_parent(proj.item_def_id) == fn_def_id.to_def_id() { + let span = tcx.def_span(proj.item_def_id); let bounds = wfcx.tcx().explicit_item_bounds(proj.item_def_id); let wf_obligations = bounds.iter().flat_map(|&(bound, bound_span)| { + let bound = ty::EarlyBinder(bound).subst(tcx, proj.substs); let normalized_bound = wfcx.normalize(span, None, bound); traits::wf::predicate_obligations( wfcx.infcx, @@ -1675,14 +1711,13 @@ fn receiver_is_valid<'tcx>( // `self: Self` is always valid. if can_eq_self(receiver_ty) { - if let Err(err) = wfcx.equate_types(&cause, wfcx.param_env, self_ty, receiver_ty) { + if let Err(err) = wfcx.eq(&cause, wfcx.param_env, self_ty, receiver_ty) { infcx.err_ctxt().report_mismatched_types(&cause, self_ty, receiver_ty, err).emit(); } return true; } - let mut autoderef = - Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty, span); + let mut autoderef = Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty); // The `arbitrary_self_types` feature allows raw pointer receivers like `self: *const Self`. if arbitrary_self_types_enabled { @@ -1692,7 +1727,7 @@ fn receiver_is_valid<'tcx>( // The first type is `receiver_ty`, which we know its not equal to `self_ty`; skip it. autoderef.next(); - let receiver_trait_def_id = tcx.require_lang_item(LangItem::Receiver, None); + let receiver_trait_def_id = tcx.require_lang_item(LangItem::Receiver, Some(span)); // Keep dereferencing `receiver_ty` until we get to `self_ty`. loop { @@ -1705,9 +1740,7 @@ fn receiver_is_valid<'tcx>( if can_eq_self(potential_self_ty) { wfcx.register_obligations(autoderef.into_obligations()); - if let Err(err) = - wfcx.equate_types(&cause, wfcx.param_env, self_ty, potential_self_ty) - { + if let Err(err) = wfcx.eq(&cause, wfcx.param_env, self_ty, potential_self_ty) { infcx .err_ctxt() .report_mismatched_types(&cause, self_ty, potential_self_ty, err) @@ -1754,13 +1787,9 @@ fn receiver_is_implemented<'tcx>( receiver_ty: Ty<'tcx>, ) -> bool { let tcx = wfcx.tcx(); - let trait_ref = ty::Binder::dummy(ty::TraitRef { - def_id: receiver_trait_def_id, - substs: tcx.mk_substs_trait(receiver_ty, &[]), - }); + let trait_ref = ty::Binder::dummy(tcx.mk_trait_ref(receiver_trait_def_id, [receiver_ty])); - let obligation = - traits::Obligation::new(cause, wfcx.param_env, trait_ref.without_const().to_predicate(tcx)); + let obligation = traits::Obligation::new(tcx, cause, wfcx.param_env, trait_ref); if wfcx.infcx.predicate_must_hold_modulo_regions(&obligation) { true @@ -1907,6 +1936,7 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> { } let obligation = traits::Obligation::new( + tcx, traits::ObligationCause::new(span, self.body_id, traits::TrivialBound), empty_env, pred, @@ -1925,56 +1955,6 @@ fn check_mod_type_wf(tcx: TyCtxt<'_>, module: LocalDefId) { items.par_foreign_items(|item| tcx.ensure().check_well_formed(item.owner_id)); } -/////////////////////////////////////////////////////////////////////////// -// ADT - -// FIXME(eddyb) replace this with getting fields/discriminants through `ty::AdtDef`. -struct AdtVariant<'tcx> { - /// Types of fields in the variant, that must be well-formed. - fields: Vec<AdtField<'tcx>>, - - /// Explicit discriminant of this variant (e.g. `A = 123`), - /// that must evaluate to a constant value. - explicit_discr: Option<LocalDefId>, -} - -struct AdtField<'tcx> { - ty: Ty<'tcx>, - def_id: LocalDefId, - span: Span, -} - -impl<'a, 'tcx> WfCheckingCtxt<'a, 'tcx> { - // FIXME(eddyb) replace this with getting fields through `ty::AdtDef`. - fn non_enum_variant(&self, struct_def: &hir::VariantData<'_>) -> AdtVariant<'tcx> { - let fields = struct_def - .fields() - .iter() - .map(|field| { - let def_id = self.tcx().hir().local_def_id(field.hir_id); - let field_ty = self.tcx().type_of(def_id); - let field_ty = self.normalize(field.ty.span, None, field_ty); - debug!("non_enum_variant: type of field {:?} is {:?}", field, field_ty); - AdtField { ty: field_ty, span: field.ty.span, def_id } - }) - .collect(); - AdtVariant { fields, explicit_discr: None } - } - - fn enum_variants(&self, enum_def: &hir::EnumDef<'_>) -> Vec<AdtVariant<'tcx>> { - enum_def - .variants - .iter() - .map(|variant| AdtVariant { - fields: self.non_enum_variant(&variant.data).fields, - explicit_discr: variant - .disr_expr - .map(|explicit_discr| self.tcx().hir().local_def_id(explicit_discr.hir_id)), - }) - .collect() - } -} - fn error_392( tcx: TyCtxt<'_>, span: Span, diff --git a/compiler/rustc_hir_analysis/src/check_unused.rs b/compiler/rustc_hir_analysis/src/check_unused.rs index d0c317334..5749b0478 100644 --- a/compiler/rustc_hir_analysis/src/check_unused.rs +++ b/compiler/rustc_hir_analysis/src/check_unused.rs @@ -57,25 +57,6 @@ fn unused_crates_lint(tcx: TyCtxt<'_>) { .maybe_unused_extern_crates(()) .iter() .filter(|&&(def_id, _)| { - // The `def_id` here actually was calculated during resolution (at least - // at the time of this writing) and is being shipped to us via a side - // channel of the tcx. There may have been extra expansion phases, - // however, which ended up removing the `def_id` *after* expansion. - // - // As a result we need to verify that `def_id` is indeed still valid for - // our AST and actually present in the HIR map. If it's not there then - // there's safely nothing to warn about, and otherwise we carry on with - // our execution. - // - // Note that if we carry through to the `extern_mod_stmt_cnum` query - // below it'll cause a panic because `def_id` is actually bogus at this - // point in time otherwise. - if tcx.hir().find(tcx.hir().local_def_id_to_hir_id(def_id)).is_none() { - return false; - } - true - }) - .filter(|&&(def_id, _)| { tcx.extern_mod_stmt_cnum(def_id).map_or(true, |cnum| { !tcx.is_compiler_builtins(cnum) && !tcx.is_panic_runtime(cnum) diff --git a/compiler/rustc_hir_analysis/src/coherence/builtin.rs b/compiler/rustc_hir_analysis/src/coherence/builtin.rs index b6c91d425..193ecdb16 100644 --- a/compiler/rustc_hir_analysis/src/coherence/builtin.rs +++ b/compiler/rustc_hir_analysis/src/coherence/builtin.rs @@ -114,7 +114,7 @@ fn visit_implementation_of_copy(tcx: TyCtxt<'_>, impl_did: LocalDefId) { traits::ObligationCause::dummy_with_span(field_ty_span), param_env, ty, - tcx.lang_items().copy_trait().unwrap(), + tcx.require_lang_item(LangItem::Copy, Some(span)), ) { let error_predicate = error.obligation.predicate; // Only note if it's not the root obligation, otherwise it's trivial and @@ -128,11 +128,11 @@ fn visit_implementation_of_copy(tcx: TyCtxt<'_>, impl_did: LocalDefId) { .or_default() .push(error.obligation.cause.span); } - if let ty::PredicateKind::Trait(ty::TraitPredicate { + if let ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate { trait_ref, polarity: ty::ImplPolarity::Positive, .. - }) = error_predicate.kind().skip_binder() + })) = error_predicate.kind().skip_binder() { let ty = trait_ref.self_ty(); if let ty::Param(_) = ty.kind() { @@ -315,13 +315,12 @@ fn visit_implementation_of_dispatch_from_dyn<'tcx>(tcx: TyCtxt<'tcx>, impl_did: cause.clone(), dispatch_from_dyn_trait, 0, - field.ty(tcx, substs_a), - &[field.ty(tcx, substs_b).into()], + [field.ty(tcx, substs_a), field.ty(tcx, substs_b)], ) }), ); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); } // Finally, resolve all regions. @@ -371,7 +370,7 @@ pub fn coerce_unsized_info<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) -> CoerceUn let check_mutbl = |mt_a: ty::TypeAndMut<'tcx>, mt_b: ty::TypeAndMut<'tcx>, mk_ptr: &dyn Fn(Ty<'tcx>) -> Ty<'tcx>| { - if (mt_a.mutbl, mt_b.mutbl) == (hir::Mutability::Not, hir::Mutability::Mut) { + if mt_a.mutbl < mt_b.mutbl { infcx .err_ctxt() .report_mismatched_types( @@ -558,10 +557,10 @@ pub fn coerce_unsized_info<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) -> CoerceUn // Register an obligation for `A: Trait<B>`. let cause = traits::ObligationCause::misc(span, impl_hir_id); let predicate = - predicate_for_trait_def(tcx, param_env, cause, trait_def_id, 0, source, &[target.into()]); + predicate_for_trait_def(tcx, param_env, cause, trait_def_id, 0, [source, target]); let errors = traits::fully_solve_obligation(&infcx, predicate); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); } // Finally, resolve all regions. diff --git a/compiler/rustc_hir_analysis/src/coherence/mod.rs b/compiler/rustc_hir_analysis/src/coherence/mod.rs index ae9ebe590..1bf3768fe 100644 --- a/compiler/rustc_hir_analysis/src/coherence/mod.rs +++ b/compiler/rustc_hir_analysis/src/coherence/mod.rs @@ -5,10 +5,11 @@ // done by the orphan and overlap modules. Then we build up various // mappings. That mapping code resides here. -use rustc_errors::struct_span_err; +use rustc_errors::{error_code, struct_span_err}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::ty::query::Providers; use rustc_middle::ty::{self, TyCtxt, TypeVisitable}; +use rustc_span::sym; use rustc_trait_selection::traits; mod builtin; @@ -39,61 +40,26 @@ fn enforce_trait_manually_implementable( impl_def_id: LocalDefId, trait_def_id: DefId, ) { - let did = Some(trait_def_id); - let li = tcx.lang_items(); let impl_header_span = tcx.def_span(impl_def_id); - // Disallow *all* explicit impls of `Pointee`, `DiscriminantKind`, `Sized` and `Unsize` for now. - if did == li.pointee_trait() { - struct_span_err!( + // Disallow *all* explicit impls of traits marked `#[rustc_deny_explicit_impl]` + if tcx.has_attr(trait_def_id, sym::rustc_deny_explicit_impl) { + let trait_name = tcx.item_name(trait_def_id); + let mut err = struct_span_err!( tcx.sess, impl_header_span, E0322, - "explicit impls for the `Pointee` trait are not permitted" - ) - .span_label(impl_header_span, "impl of `Pointee` not allowed") - .emit(); - return; - } - - if did == li.discriminant_kind_trait() { - struct_span_err!( - tcx.sess, - impl_header_span, - E0322, - "explicit impls for the `DiscriminantKind` trait are not permitted" - ) - .span_label(impl_header_span, "impl of `DiscriminantKind` not allowed") - .emit(); - return; - } - - if did == li.sized_trait() { - struct_span_err!( - tcx.sess, - impl_header_span, - E0322, - "explicit impls for the `Sized` trait are not permitted" - ) - .span_label(impl_header_span, "impl of `Sized` not allowed") - .emit(); - return; - } - - if did == li.unsize_trait() { - struct_span_err!( - tcx.sess, - impl_header_span, - E0328, - "explicit impls for the `Unsize` trait are not permitted" - ) - .span_label(impl_header_span, "impl of `Unsize` not allowed") - .emit(); - return; - } + "explicit impls for the `{trait_name}` trait are not permitted" + ); + err.span_label(impl_header_span, format!("impl of `{trait_name}` not allowed")); + + // Maintain explicit error code for `Unsize`, since it has a useful + // explanation about using `CoerceUnsized` instead. + if Some(trait_def_id) == tcx.lang_items().unsize_trait() { + err.code(error_code!(E0328)); + } - if tcx.features().unboxed_closures { - // the feature gate allows all Fn traits + err.emit(); return; } diff --git a/compiler/rustc_hir_analysis/src/coherence/orphan.rs b/compiler/rustc_hir_analysis/src/coherence/orphan.rs index bb45c3823..cc5114dba 100644 --- a/compiler/rustc_hir_analysis/src/coherence/orphan.rs +++ b/compiler/rustc_hir_analysis/src/coherence/orphan.rs @@ -5,7 +5,6 @@ use rustc_data_structures::fx::FxHashSet; use rustc_errors::{struct_span_err, DelayDm}; use rustc_errors::{Diagnostic, ErrorGuaranteed}; use rustc_hir as hir; -use rustc_middle::ty::subst::GenericArgKind; use rustc_middle::ty::subst::InternalSubsts; use rustc_middle::ty::util::IgnoreRegions; use rustc_middle::ty::{ @@ -23,9 +22,7 @@ pub(crate) fn orphan_check_impl( impl_def_id: LocalDefId, ) -> Result<(), ErrorGuaranteed> { let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap(); - if let Some(err) = trait_ref.error_reported() { - return Err(err); - } + trait_ref.error_reported()?; let ret = do_orphan_check_impl(tcx, trait_ref, impl_def_id); if tcx.trait_is_auto(trait_ref.def_id) { @@ -49,58 +46,6 @@ fn do_orphan_check_impl<'tcx>( let sp = tcx.def_span(def_id); let tr = impl_.of_trait.as_ref().unwrap(); - // Ensure no opaque types are present in this impl header. See issues #76202 and #86411 for examples, - // and #84660 where it would otherwise allow unsoundness. - if trait_ref.has_opaque_types() { - trace!("{:#?}", item); - // First we find the opaque type in question. - for ty in trait_ref.substs { - for ty in ty.walk() { - let ty::subst::GenericArgKind::Type(ty) = ty.unpack() else { continue }; - let ty::Opaque(def_id, _) = *ty.kind() else { continue }; - trace!(?def_id); - - // Then we search for mentions of the opaque type's type alias in the HIR - struct SpanFinder<'tcx> { - sp: Span, - def_id: DefId, - tcx: TyCtxt<'tcx>, - } - impl<'v, 'tcx> hir::intravisit::Visitor<'v> for SpanFinder<'tcx> { - #[instrument(level = "trace", skip(self, _id))] - fn visit_path(&mut self, path: &'v hir::Path<'v>, _id: hir::HirId) { - // You can't mention an opaque type directly, so we look for type aliases - if let hir::def::Res::Def(hir::def::DefKind::TyAlias, def_id) = path.res { - // And check if that type alias's type contains the opaque type we're looking for - for arg in self.tcx.type_of(def_id).walk() { - if let GenericArgKind::Type(ty) = arg.unpack() { - if let ty::Opaque(def_id, _) = *ty.kind() { - if def_id == self.def_id { - // Finally we update the span to the mention of the type alias - self.sp = path.span; - return; - } - } - } - } - } - hir::intravisit::walk_path(self, path) - } - } - - let mut visitor = SpanFinder { sp, def_id, tcx }; - hir::intravisit::walk_item(&mut visitor, item); - let reported = tcx - .sess - .struct_span_err(visitor.sp, "cannot implement trait on type alias impl trait") - .span_note(tcx.def_span(def_id), "type alias impl trait defined here") - .emit(); - return Err(reported); - } - } - span_bug!(sp, "opaque type not found, but `has_opaque_types` is set") - } - match traits::orphan_check(tcx, item.owner_id.to_def_id()) { Ok(()) => {} Err(err) => emit_orphan_check_error( @@ -347,7 +292,7 @@ fn emit_newtype_suggestion_for_raw_ptr( diag: &mut Diagnostic, ) { if !self_ty.needs_subst() { - let mut_key = if ptr_ty.mutbl == rustc_middle::mir::Mutability::Mut { "mut " } else { "" }; + let mut_key = ptr_ty.mutbl.prefix_str(); let msg_sugg = "consider introducing a new wrapper type".to_owned(); let sugg = vec![ ( diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs index 346d2e2fc..1183a26d5 100644 --- a/compiler/rustc_hir_analysis/src/collect.rs +++ b/compiler/rustc_hir_analysis/src/collect.rs @@ -24,18 +24,16 @@ use rustc_data_structures::captures::Captures; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed, StashKey}; use rustc_hir as hir; -use rustc_hir::def::CtorKind; use rustc_hir::def_id::{DefId, LocalDefId, LOCAL_CRATE}; use rustc_hir::intravisit::{self, Visitor}; -use rustc_hir::weak_lang_items; -use rustc_hir::{GenericParamKind, Node}; +use rustc_hir::weak_lang_items::WEAK_LANG_ITEMS; +use rustc_hir::{lang_items, GenericParamKind, LangItem, Node}; use rustc_middle::hir::nested_filter; use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs}; use rustc_middle::mir::mono::Linkage; use rustc_middle::ty::query::Providers; use rustc_middle::ty::util::{Discr, IntTypeExt}; -use rustc_middle::ty::ReprOptions; -use rustc_middle::ty::{self, AdtKind, Const, DefIdTree, IsSuggestable, Ty, TyCtxt}; +use rustc_middle::ty::{self, AdtKind, Const, DefIdTree, IsSuggestable, ToPredicate, Ty, TyCtxt}; use rustc_session::lint; use rustc_session::parse::feature_err; use rustc_span::symbol::{kw, sym, Ident, Symbol}; @@ -84,6 +82,7 @@ pub fn provide(providers: &mut Providers) { asm_target_features, collect_mod_item_types, should_inherit_track_caller, + is_type_alias_impl_trait, ..*providers }; } @@ -291,18 +290,15 @@ impl<'tcx> Visitor<'tcx> for CollectItemTypesVisitor<'tcx> { match param.kind { hir::GenericParamKind::Lifetime { .. } => {} hir::GenericParamKind::Type { default: Some(_), .. } => { - let def_id = self.tcx.hir().local_def_id(param.hir_id); - self.tcx.ensure().type_of(def_id); + self.tcx.ensure().type_of(param.def_id); } hir::GenericParamKind::Type { .. } => {} hir::GenericParamKind::Const { default, .. } => { - let def_id = self.tcx.hir().local_def_id(param.hir_id); - self.tcx.ensure().type_of(def_id); + self.tcx.ensure().type_of(param.def_id); if let Some(default) = default { - let default_def_id = self.tcx.hir().local_def_id(default.hir_id); // need to store default and type of default - self.tcx.ensure().type_of(default_def_id); - self.tcx.ensure().const_param_default(def_id); + self.tcx.ensure().type_of(default.def_id); + self.tcx.ensure().const_param_default(param.def_id); } } } @@ -311,9 +307,9 @@ impl<'tcx> Visitor<'tcx> for CollectItemTypesVisitor<'tcx> { } fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) { - if let hir::ExprKind::Closure { .. } = expr.kind { - let def_id = self.tcx.hir().local_def_id(expr.hir_id); - self.tcx.ensure().generics_of(def_id); + if let hir::ExprKind::Closure(closure) = expr.kind { + self.tcx.ensure().generics_of(closure.def_id); + self.tcx.ensure().codegen_fn_attrs(closure.def_id); // We do not call `type_of` for closures here as that // depends on typecheck and would therefore hide // any further errors in case one typeck fails. @@ -379,8 +375,8 @@ impl<'tcx> AstConv<'tcx> for ItemCtxt<'tcx> { self.tcx } - fn item_def_id(&self) -> Option<DefId> { - Some(self.item_def_id) + fn item_def_id(&self) -> DefId { + self.item_def_id } fn get_type_parameter_bounds( @@ -512,8 +508,7 @@ impl<'tcx> AstConv<'tcx> for ItemCtxt<'tcx> { } _ => {} } - err.emit(); - self.tcx().ty_error() + self.tcx().ty_error_with_guaranteed(err.emit()) } } @@ -522,7 +517,7 @@ impl<'tcx> AstConv<'tcx> for ItemCtxt<'tcx> { ty } - fn set_tainted_by_errors(&self) { + fn set_tainted_by_errors(&self, _: ErrorGuaranteed) { // There's no obvious place to track this, so just let it go. } @@ -587,8 +582,12 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) { tcx.ensure().type_of(item.owner_id); tcx.ensure().predicates_of(item.owner_id); match item.kind { - hir::ForeignItemKind::Fn(..) => tcx.ensure().fn_sig(item.owner_id), + hir::ForeignItemKind::Fn(..) => { + tcx.ensure().codegen_fn_attrs(item.owner_id); + tcx.ensure().fn_sig(item.owner_id) + } hir::ForeignItemKind::Static(..) => { + tcx.ensure().codegen_fn_attrs(item.owner_id); let mut visitor = HirPlaceholderCollector::default(); visitor.visit_foreign_item(item); placeholder_type_error( @@ -604,11 +603,11 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) { } } } - hir::ItemKind::Enum(ref enum_definition, _) => { + hir::ItemKind::Enum(..) => { tcx.ensure().generics_of(def_id); tcx.ensure().type_of(def_id); tcx.ensure().predicates_of(def_id); - convert_enum_variant_types(tcx, def_id.to_def_id(), enum_definition.variants); + convert_enum_variant_types(tcx, def_id.to_def_id()); } hir::ItemKind::Impl { .. } => { tcx.ensure().generics_of(def_id); @@ -633,23 +632,16 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) { tcx.ensure().predicates_of(def_id); for f in struct_def.fields() { - let def_id = tcx.hir().local_def_id(f.hir_id); - tcx.ensure().generics_of(def_id); - tcx.ensure().type_of(def_id); - tcx.ensure().predicates_of(def_id); + tcx.ensure().generics_of(f.def_id); + tcx.ensure().type_of(f.def_id); + tcx.ensure().predicates_of(f.def_id); } - if let Some(ctor_hir_id) = struct_def.ctor_hir_id() { - convert_variant_ctor(tcx, ctor_hir_id); + if let Some(ctor_def_id) = struct_def.ctor_def_id() { + convert_variant_ctor(tcx, ctor_def_id); } } - // Desugared from `impl Trait`, so visited by the function's return type. - hir::ItemKind::OpaqueTy(hir::OpaqueTy { - origin: hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..), - .. - }) => {} - // Don't call `type_of` on opaque types, since that depends on type // checking function bodies. `check_item_type` ensures that it's called // instead. @@ -657,27 +649,33 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) { tcx.ensure().generics_of(def_id); tcx.ensure().predicates_of(def_id); tcx.ensure().explicit_item_bounds(def_id); + tcx.ensure().item_bounds(def_id); } - hir::ItemKind::TyAlias(..) - | hir::ItemKind::Static(..) - | hir::ItemKind::Const(..) - | hir::ItemKind::Fn(..) => { + + hir::ItemKind::TyAlias(..) => { tcx.ensure().generics_of(def_id); tcx.ensure().type_of(def_id); tcx.ensure().predicates_of(def_id); - match it.kind { - hir::ItemKind::Fn(..) => tcx.ensure().fn_sig(def_id), - hir::ItemKind::OpaqueTy(..) => tcx.ensure().item_bounds(def_id), - hir::ItemKind::Const(ty, ..) | hir::ItemKind::Static(ty, ..) => { - if !is_suggestable_infer_ty(ty) { - let mut visitor = HirPlaceholderCollector::default(); - visitor.visit_item(it); - placeholder_type_error(tcx, None, visitor.0, false, None, it.kind.descr()); - } - } - _ => (), + } + + hir::ItemKind::Static(ty, ..) | hir::ItemKind::Const(ty, ..) => { + tcx.ensure().generics_of(def_id); + tcx.ensure().type_of(def_id); + tcx.ensure().predicates_of(def_id); + if !is_suggestable_infer_ty(ty) { + let mut visitor = HirPlaceholderCollector::default(); + visitor.visit_item(it); + placeholder_type_error(tcx, None, visitor.0, false, None, it.kind.descr()); } } + + hir::ItemKind::Fn(..) => { + tcx.ensure().generics_of(def_id); + tcx.ensure().type_of(def_id); + tcx.ensure().predicates_of(def_id); + tcx.ensure().fn_sig(def_id); + tcx.ensure().codegen_fn_attrs(def_id); + } } } @@ -688,6 +686,7 @@ fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) { match trait_item.kind { hir::TraitItemKind::Fn(..) => { + tcx.ensure().codegen_fn_attrs(def_id); tcx.ensure().type_of(def_id); tcx.ensure().fn_sig(def_id); } @@ -737,6 +736,7 @@ fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::ImplItemId) { let impl_item = tcx.hir().impl_item(impl_item_id); match impl_item.kind { hir::ImplItemKind::Fn(..) => { + tcx.ensure().codegen_fn_attrs(def_id); tcx.ensure().fn_sig(def_id); } hir::ImplItemKind::Type(_) => { @@ -750,37 +750,34 @@ fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::ImplItemId) { } } -fn convert_variant_ctor(tcx: TyCtxt<'_>, ctor_id: hir::HirId) { - let def_id = tcx.hir().local_def_id(ctor_id); +fn convert_variant_ctor(tcx: TyCtxt<'_>, def_id: LocalDefId) { tcx.ensure().generics_of(def_id); tcx.ensure().type_of(def_id); tcx.ensure().predicates_of(def_id); } -fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::Variant<'_>]) { +fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId) { let def = tcx.adt_def(def_id); let repr_type = def.repr().discr_type(); let initial = repr_type.initial_discriminant(tcx); let mut prev_discr = None::<Discr<'_>>; // fill the discriminant values and field types - for variant in variants { + for variant in def.variants() { let wrapped_discr = prev_discr.map_or(initial, |d| d.wrap_incr(tcx)); prev_discr = Some( - if let Some(ref e) = variant.disr_expr { - let expr_did = tcx.hir().local_def_id(e.hir_id); - def.eval_explicit_discr(tcx, expr_did.to_def_id()) + if let ty::VariantDiscr::Explicit(const_def_id) = variant.discr { + def.eval_explicit_discr(tcx, const_def_id) } else if let Some(discr) = repr_type.disr_incr(tcx, prev_discr) { Some(discr) } else { - struct_span_err!(tcx.sess, variant.span, E0370, "enum discriminant overflowed") - .span_label( - variant.span, - format!("overflowed on value after {}", prev_discr.unwrap()), - ) + let span = tcx.def_span(variant.def_id); + struct_span_err!(tcx.sess, span, E0370, "enum discriminant overflowed") + .span_label(span, format!("overflowed on value after {}", prev_discr.unwrap())) .note(&format!( "explicitly set `{} = {}` if that is desired outcome", - variant.ident, wrapped_discr + tcx.item_name(variant.def_id), + wrapped_discr )) .emit(); None @@ -788,17 +785,16 @@ fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::V .unwrap_or(wrapped_discr), ); - for f in variant.data.fields() { - let def_id = tcx.hir().local_def_id(f.hir_id); - tcx.ensure().generics_of(def_id); - tcx.ensure().type_of(def_id); - tcx.ensure().predicates_of(def_id); + for f in &variant.fields { + tcx.ensure().generics_of(f.did); + tcx.ensure().type_of(f.did); + tcx.ensure().predicates_of(f.did); } // Convert the ctor, if any. This also registers the variant as // an item. - if let Some(ctor_hir_id) = variant.data.ctor_hir_id() { - convert_variant_ctor(tcx, ctor_hir_id); + if let Some(ctor_def_id) = variant.ctor_def_id() { + convert_variant_ctor(tcx, ctor_def_id.expect_local()); } } } @@ -806,7 +802,6 @@ fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::V fn convert_variant( tcx: TyCtxt<'_>, variant_did: Option<LocalDefId>, - ctor_did: Option<LocalDefId>, ident: Ident, discr: ty::VariantDiscr, def: &hir::VariantData<'_>, @@ -818,7 +813,6 @@ fn convert_variant( .fields() .iter() .map(|f| { - let fid = tcx.hir().local_def_id(f.hir_id); let dup_span = seen_fields.get(&f.ident.normalize_to_macros_2_0()).cloned(); if let Some(prev_span) = dup_span { tcx.sess.emit_err(errors::FieldAlreadyDeclared { @@ -830,7 +824,11 @@ fn convert_variant( seen_fields.insert(f.ident.normalize_to_macros_2_0(), f.span); } - ty::FieldDef { did: fid.to_def_id(), name: f.ident.name, vis: tcx.visibility(fid) } + ty::FieldDef { + did: f.def_id.to_def_id(), + name: f.ident.name, + vis: tcx.visibility(f.def_id), + } }) .collect(); let recovered = match def { @@ -840,10 +838,9 @@ fn convert_variant( ty::VariantDef::new( ident.name, variant_did.map(LocalDefId::to_def_id), - ctor_did.map(LocalDefId::to_def_id), + def.ctor().map(|(kind, _, def_id)| (kind, def_id.to_def_id())), discr, fields, - CtorKind::from_hir(def), adt_kind, parent_did.to_def_id(), recovered, @@ -863,7 +860,7 @@ fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::AdtDef<'tcx> { bug!(); }; - let repr = ReprOptions::new(tcx, def_id.to_def_id()); + let repr = tcx.repr_options_of_def(def_id.to_def_id()); let (kind, variants) = match item.kind { ItemKind::Enum(ref def, _) => { let mut distance_from_explicit = 0; @@ -871,13 +868,9 @@ fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::AdtDef<'tcx> { .variants .iter() .map(|v| { - let variant_did = Some(tcx.hir().local_def_id(v.id)); - let ctor_did = - v.data.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id)); - let discr = if let Some(ref e) = v.disr_expr { distance_from_explicit = 0; - ty::VariantDiscr::Explicit(tcx.hir().local_def_id(e.hir_id).to_def_id()) + ty::VariantDiscr::Explicit(e.def_id.to_def_id()) } else { ty::VariantDiscr::Relative(distance_from_explicit) }; @@ -885,8 +878,7 @@ fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::AdtDef<'tcx> { convert_variant( tcx, - variant_did, - ctor_did, + Some(v.def_id), v.ident, discr, &v.data, @@ -898,41 +890,23 @@ fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::AdtDef<'tcx> { (AdtKind::Enum, variants) } - ItemKind::Struct(ref def, _) => { - let variant_did = None::<LocalDefId>; - let ctor_did = def.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id)); - - let variants = std::iter::once(convert_variant( - tcx, - variant_did, - ctor_did, - item.ident, - ty::VariantDiscr::Relative(0), - def, - AdtKind::Struct, - def_id, - )) - .collect(); - - (AdtKind::Struct, variants) - } - ItemKind::Union(ref def, _) => { - let variant_did = None; - let ctor_did = def.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id)); - + ItemKind::Struct(ref def, _) | ItemKind::Union(ref def, _) => { + let adt_kind = match item.kind { + ItemKind::Struct(..) => AdtKind::Struct, + _ => AdtKind::Union, + }; let variants = std::iter::once(convert_variant( tcx, - variant_did, - ctor_did, + None, item.ident, ty::VariantDiscr::Relative(0), def, - AdtKind::Union, + adt_kind, def_id, )) .collect(); - (AdtKind::Union, variants) + (adt_kind, variants) } _ => bug!(), }; @@ -1181,10 +1155,9 @@ fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> { compute_sig_of_foreign_fn_decl(tcx, def_id.to_def_id(), fn_decl, abi) } - Ctor(data) | Variant(hir::Variant { data, .. }) if data.ctor_hir_id().is_some() => { + Ctor(data) | Variant(hir::Variant { data, .. }) if data.ctor().is_some() => { let ty = tcx.type_of(tcx.hir().get_parent_item(hir_id)); - let inputs = - data.fields().iter().map(|f| tcx.type_of(tcx.hir().local_def_id(f.hir_id))); + let inputs = data.fields().iter().map(|f| tcx.type_of(f.def_id)); ty::Binder::dummy(tcx.mk_fn_sig( inputs, ty, @@ -1394,12 +1367,14 @@ fn predicates_defined_on(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicate "predicates_defined_on: inferred_outlives_of({:?}) = {:?}", def_id, inferred_outlives, ); + let inferred_outlives_iter = + inferred_outlives.iter().map(|(clause, span)| ((*clause).to_predicate(tcx), *span)); if result.predicates.is_empty() { - result.predicates = inferred_outlives; + result.predicates = tcx.arena.alloc_from_iter(inferred_outlives_iter); } else { - result.predicates = tcx - .arena - .alloc_from_iter(result.predicates.iter().chain(inferred_outlives).copied()); + result.predicates = tcx.arena.alloc_from_iter( + result.predicates.into_iter().copied().chain(inferred_outlives_iter), + ); } } @@ -1840,7 +1815,12 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs { ); } else if attr.has_name(sym::linkage) { if let Some(val) = attr.value_str() { - codegen_fn_attrs.linkage = Some(linkage_by_name(tcx, did, val.as_str())); + let linkage = Some(linkage_by_name(tcx, did, val.as_str())); + if tcx.is_foreign_item(did) { + codegen_fn_attrs.import_linkage = linkage; + } else { + codegen_fn_attrs.linkage = linkage; + } } } else if attr.has_name(sym::link_section) { if let Some(val) = attr.value_str() { @@ -2099,17 +2079,25 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs { } } + if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::NAKED) { + codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_COVERAGE; + codegen_fn_attrs.inline = InlineAttr::Never; + } + // Weak lang items have the same semantics as "std internal" symbols in the // sense that they're preserved through all our LTO passes and only // strippable by the linker. // // Additionally weak lang items have predetermined symbol names. - if tcx.is_weak_lang_item(did.to_def_id()) { + if WEAK_LANG_ITEMS.iter().any(|&l| tcx.lang_items().get(l) == Some(did.to_def_id())) { codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL; } - if let Some(name) = weak_lang_items::link_name(attrs) { - codegen_fn_attrs.export_name = Some(name); - codegen_fn_attrs.link_name = Some(name); + if let Some((name, _)) = lang_items::extract(attrs) + && let Some(lang_item) = LangItem::from_name(name) + && let Some(link_name) = lang_item.link_name() + { + codegen_fn_attrs.export_name = Some(link_name); + codegen_fn_attrs.link_name = Some(link_name); } check_link_name_xor_ordinal(tcx, &codegen_fn_attrs, link_ordinal_span); @@ -2170,7 +2158,7 @@ fn should_inherit_track_caller(tcx: TyCtxt<'_>, def_id: DefId) -> bool { } fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<u16> { - use rustc_ast::{Lit, LitIntType, LitKind}; + use rustc_ast::{LitIntType, LitKind, MetaItemLit}; if !tcx.features().raw_dylib && tcx.sess.target.arch == "x86" { feature_err( &tcx.sess.parse_sess, @@ -2181,9 +2169,9 @@ fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<u16> { .emit(); } let meta_item_list = attr.meta_item_list(); - let meta_item_list: Option<&[ast::NestedMetaItem]> = meta_item_list.as_ref().map(Vec::as_ref); + let meta_item_list = meta_item_list.as_deref(); let sole_meta_list = match meta_item_list { - Some([item]) => item.literal(), + Some([item]) => item.lit(), Some(_) => { tcx.sess .struct_span_err(attr.span, "incorrect number of arguments to `#[link_ordinal]`") @@ -2193,7 +2181,9 @@ fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<u16> { } _ => None, }; - if let Some(Lit { kind: LitKind::Int(ordinal, LitIntType::Unsuffixed), .. }) = sole_meta_list { + if let Some(MetaItemLit { kind: LitKind::Int(ordinal, LitIntType::Unsuffixed), .. }) = + sole_meta_list + { // According to the table at https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#import-header, // the ordinal must fit into 16 bits. Similarly, the Ordinal field in COFFShortExport (defined // in llvm/include/llvm/Object/COFFImportFile.h), which we use to communicate import information @@ -2261,3 +2251,13 @@ fn check_target_feature_trait_unsafe(tcx: TyCtxt<'_>, id: LocalDefId, attr_span: } } } + +fn is_type_alias_impl_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool { + match tcx.hir().get_if_local(def_id) { + Some(Node::Item(hir::Item { kind: hir::ItemKind::OpaqueTy(opaque), .. })) => { + matches!(opaque.origin, hir::OpaqueTyOrigin::TyAlias) + } + Some(_) => bug!("tried getting opaque_ty_origin for non-opaque: {:?}", def_id), + _ => bug!("tried getting opaque_ty_origin for non-local def-id {:?}", def_id), + } +} diff --git a/compiler/rustc_hir_analysis/src/collect/generics_of.rs b/compiler/rustc_hir_analysis/src/collect/generics_of.rs index c7777a946..639f81f20 100644 --- a/compiler/rustc_hir_analysis/src/collect/generics_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/generics_of.rs @@ -51,7 +51,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics { // of a const parameter type, e.g. `struct Foo<const N: usize, const M: [u8; N]>` is not allowed. None } else if tcx.lazy_normalization() { - if let Some(param_id) = tcx.hir().opt_const_param_default_param_hir_id(hir_id) { + if let Some(param_id) = tcx.hir().opt_const_param_default_param_def_id(hir_id) { // If the def_id we are calling generics_of on is an anon ct default i.e: // // struct Foo<const N: usize = { .. }>; @@ -77,8 +77,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics { // This has some implications for how we get the predicates available to the anon const // see `explicit_predicates_of` for more information on this let generics = tcx.generics_of(parent_def_id.to_def_id()); - let param_def = tcx.hir().local_def_id(param_id).to_def_id(); - let param_def_idx = generics.param_def_id_to_index[¶m_def]; + let param_def_idx = generics.param_def_id_to_index[¶m_id.to_def_id()]; // In the above example this would be .params[..N#0] let params = generics.params[..param_def_idx as usize].to_owned(); let param_def_id_to_index = @@ -241,7 +240,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics { params.extend(early_lifetimes.enumerate().map(|(i, param)| ty::GenericParamDef { name: param.name.ident().name, index: own_start + i as u32, - def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(), + def_id: param.def_id.to_def_id(), pure_wrt_drop: param.pure_wrt_drop, kind: ty::GenericParamDefKind::Lifetime, })); @@ -286,7 +285,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics { Some(ty::GenericParamDef { index: next_index(), name: param.name.ident().name, - def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(), + def_id: param.def_id.to_def_id(), pure_wrt_drop: param.pure_wrt_drop, kind, }) @@ -303,7 +302,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics { Some(ty::GenericParamDef { index: next_index(), name: param.name.ident().name, - def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(), + def_id: param.def_id.to_def_id(), pure_wrt_drop: param.pure_wrt_drop, kind: ty::GenericParamDefKind::Const { has_default: default.is_some() }, }) @@ -399,7 +398,7 @@ fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<S Some(rl::Region::Static | rl::Region::EarlyBound(..)) => {} Some(rl::Region::LateBound(debruijn, _, _)) if debruijn < self.outer_index => {} Some(rl::Region::LateBound(..) | rl::Region::Free(..)) | None => { - self.has_late_bound_regions = Some(lt.span); + self.has_late_bound_regions = Some(lt.ident.span); } } } diff --git a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs index 0d34a8bfe..0542e2c8f 100644 --- a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs +++ b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs @@ -35,9 +35,11 @@ fn associated_type_bounds<'tcx>( let bounds_from_parent = trait_predicates.predicates.iter().copied().filter(|(pred, _)| { match pred.kind().skip_binder() { - ty::PredicateKind::Trait(tr) => tr.self_ty() == item_ty, - ty::PredicateKind::Projection(proj) => proj.projection_ty.self_ty() == item_ty, - ty::PredicateKind::TypeOutlives(outlives) => outlives.0 == item_ty, + ty::PredicateKind::Clause(ty::Clause::Trait(tr)) => tr.self_ty() == item_ty, + ty::PredicateKind::Clause(ty::Clause::Projection(proj)) => { + proj.projection_ty.self_ty() == item_ty + } + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(outlives)) => outlives.0 == item_ty, _ => false, } }); diff --git a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs index 3f263a6de..e4fe3e90e 100644 --- a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs +++ b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs @@ -15,19 +15,18 @@ use rustc_hir::def_id::LocalDefId; use rustc_hir::intravisit::{self, Visitor}; use rustc_hir::{GenericArg, GenericParam, GenericParamKind, HirIdMap, LifetimeName, Node}; use rustc_middle::bug; -use rustc_middle::hir::map::Map; use rustc_middle::hir::nested_filter; use rustc_middle::middle::resolve_lifetime::*; -use rustc_middle::ty::{self, DefIdTree, TyCtxt}; +use rustc_middle::ty::{self, DefIdTree, TyCtxt, TypeSuperVisitable, TypeVisitor}; use rustc_span::def_id::DefId; use rustc_span::symbol::{sym, Ident}; use rustc_span::Span; use std::fmt; trait RegionExt { - fn early(hir_map: Map<'_>, param: &GenericParam<'_>) -> (LocalDefId, Region); + fn early(param: &GenericParam<'_>) -> (LocalDefId, Region); - fn late(index: u32, hir_map: Map<'_>, param: &GenericParam<'_>) -> (LocalDefId, Region); + fn late(index: u32, param: &GenericParam<'_>) -> (LocalDefId, Region); fn id(&self) -> Option<DefId>; @@ -35,20 +34,18 @@ trait RegionExt { } impl RegionExt for Region { - fn early(hir_map: Map<'_>, param: &GenericParam<'_>) -> (LocalDefId, Region) { - let def_id = hir_map.local_def_id(param.hir_id); - debug!("Region::early: def_id={:?}", def_id); - (def_id, Region::EarlyBound(def_id.to_def_id())) + fn early(param: &GenericParam<'_>) -> (LocalDefId, Region) { + debug!("Region::early: def_id={:?}", param.def_id); + (param.def_id, Region::EarlyBound(param.def_id.to_def_id())) } - fn late(idx: u32, hir_map: Map<'_>, param: &GenericParam<'_>) -> (LocalDefId, Region) { + fn late(idx: u32, param: &GenericParam<'_>) -> (LocalDefId, Region) { let depth = ty::INNERMOST; - let def_id = hir_map.local_def_id(param.hir_id); debug!( "Region::late: idx={:?}, param={:?} depth={:?} def_id={:?}", - idx, param, depth, def_id, + idx, param, depth, param.def_id, ); - (def_id, Region::LateBound(depth, idx, def_id.to_def_id())) + (param.def_id, Region::LateBound(depth, idx, param.def_id.to_def_id())) } fn id(&self) -> Option<DefId> { @@ -94,11 +91,6 @@ struct LifetimeContext<'a, 'tcx> { tcx: TyCtxt<'tcx>, map: &'a mut NamedRegionMap, scope: ScopeRef<'a>, - - /// Indicates that we only care about the definition of a trait. This should - /// be false if the `Item` we are resolving lifetimes for is not a trait or - /// we eventually need lifetimes resolve for trait items. - trait_definition_only: bool, } #[derive(Debug)] @@ -166,7 +158,9 @@ enum Scope<'a> { s: ScopeRef<'a>, }, - Root, + Root { + opt_parent_item: Option<LocalDefId>, + }, } #[derive(Copy, Clone, Debug)] @@ -214,95 +208,58 @@ impl<'a> fmt::Debug for TruncatedScopeDebug<'a> { .field("s", &"..") .finish(), Scope::TraitRefBoundary { s: _ } => f.debug_struct("TraitRefBoundary").finish(), - Scope::Root => f.debug_struct("Root").finish(), + Scope::Root { opt_parent_item } => { + f.debug_struct("Root").field("opt_parent_item", &opt_parent_item).finish() + } } } } type ScopeRef<'a> = &'a Scope<'a>; -const ROOT_SCOPE: ScopeRef<'static> = &Scope::Root; - pub(crate) fn provide(providers: &mut ty::query::Providers) { *providers = ty::query::Providers { - resolve_lifetimes_trait_definition, resolve_lifetimes, - named_region_map: |tcx, id| resolve_lifetimes_for(tcx, id).defs.get(&id), + named_region_map: |tcx, id| tcx.resolve_lifetimes(id).defs.get(&id), is_late_bound_map, object_lifetime_default, - late_bound_vars_map: |tcx, id| resolve_lifetimes_for(tcx, id).late_bound_vars.get(&id), + late_bound_vars_map: |tcx, id| tcx.resolve_lifetimes(id).late_bound_vars.get(&id), ..*providers }; } -/// Like `resolve_lifetimes`, but does not resolve lifetimes for trait items. -/// Also does not generate any diagnostics. -/// -/// This is ultimately a subset of the `resolve_lifetimes` work. It effectively -/// resolves lifetimes only within the trait "header" -- that is, the trait -/// and supertrait list. In contrast, `resolve_lifetimes` resolves all the -/// lifetimes within the trait and its items. There is room to refactor this, -/// for example to resolve lifetimes for each trait item in separate queries, -/// but it's convenient to do the entire trait at once because the lifetimes -/// from the trait definition are in scope within the trait items as well. -/// -/// The reason for this separate call is to resolve what would otherwise -/// be a cycle. Consider this example: -/// -/// ```ignore UNSOLVED (maybe @jackh726 knows what lifetime parameter to give Sub) -/// trait Base<'a> { -/// type BaseItem; -/// } -/// trait Sub<'b>: for<'a> Base<'a> { -/// type SubItem: Sub<BaseItem = &'b u32>; -/// } -/// ``` -/// -/// When we resolve `Sub` and all its items, we also have to resolve `Sub<BaseItem = &'b u32>`. -/// To figure out the index of `'b`, we have to know about the supertraits -/// of `Sub` so that we can determine that the `for<'a>` will be in scope. -/// (This is because we -- currently at least -- flatten all the late-bound -/// lifetimes into a single binder.) This requires us to resolve the -/// *trait definition* of `Sub`; basically just enough lifetime information -/// to look at the supertraits. -#[instrument(level = "debug", skip(tcx))] -fn resolve_lifetimes_trait_definition( - tcx: TyCtxt<'_>, - local_def_id: LocalDefId, -) -> ResolveLifetimes { - convert_named_region_map(do_resolve(tcx, local_def_id, true)) -} - /// Computes the `ResolveLifetimes` map that contains data for an entire `Item`. /// You should not read the result of this query directly, but rather use /// `named_region_map`, `is_late_bound_map`, etc. #[instrument(level = "debug", skip(tcx))] -fn resolve_lifetimes(tcx: TyCtxt<'_>, local_def_id: LocalDefId) -> ResolveLifetimes { - convert_named_region_map(do_resolve(tcx, local_def_id, false)) -} - -fn do_resolve( - tcx: TyCtxt<'_>, - local_def_id: LocalDefId, - trait_definition_only: bool, -) -> NamedRegionMap { - let item = tcx.hir().expect_item(local_def_id); +fn resolve_lifetimes(tcx: TyCtxt<'_>, local_def_id: hir::OwnerId) -> ResolveLifetimes { let mut named_region_map = NamedRegionMap { defs: Default::default(), late_bound_vars: Default::default() }; let mut visitor = LifetimeContext { tcx, map: &mut named_region_map, - scope: ROOT_SCOPE, - trait_definition_only, + scope: &Scope::Root { opt_parent_item: None }, }; - visitor.visit_item(item); - - named_region_map -} + match tcx.hir().owner(local_def_id) { + hir::OwnerNode::Item(item) => visitor.visit_item(item), + hir::OwnerNode::ForeignItem(item) => visitor.visit_foreign_item(item), + hir::OwnerNode::TraitItem(item) => { + let scope = + Scope::Root { opt_parent_item: Some(tcx.local_parent(item.owner_id.def_id)) }; + visitor.scope = &scope; + visitor.visit_trait_item(item) + } + hir::OwnerNode::ImplItem(item) => { + let scope = + Scope::Root { opt_parent_item: Some(tcx.local_parent(item.owner_id.def_id)) }; + visitor.scope = &scope; + visitor.visit_impl_item(item) + } + hir::OwnerNode::Crate(_) => {} + } -fn convert_named_region_map(named_region_map: NamedRegionMap) -> ResolveLifetimes { let mut rl = ResolveLifetimes::default(); for (hir_id, v) in named_region_map.defs { @@ -319,53 +276,6 @@ fn convert_named_region_map(named_region_map: NamedRegionMap) -> ResolveLifetime rl } -/// Given `any` owner (structs, traits, trait methods, etc.), does lifetime resolution. -/// There are two important things this does. -/// First, we have to resolve lifetimes for -/// the entire *`Item`* that contains this owner, because that's the largest "scope" -/// where we can have relevant lifetimes. -/// Second, if we are asking for lifetimes in a trait *definition*, we use `resolve_lifetimes_trait_definition` -/// instead of `resolve_lifetimes`, which does not descend into the trait items and does not emit diagnostics. -/// This allows us to avoid cycles. Importantly, if we ask for lifetimes for lifetimes that have an owner -/// other than the trait itself (like the trait methods or associated types), then we just use the regular -/// `resolve_lifetimes`. -fn resolve_lifetimes_for<'tcx>(tcx: TyCtxt<'tcx>, def_id: hir::OwnerId) -> &'tcx ResolveLifetimes { - let item_id = item_for(tcx, def_id.def_id); - let local_def_id = item_id.owner_id.def_id; - if item_id.owner_id == def_id { - let item = tcx.hir().item(item_id); - match item.kind { - hir::ItemKind::Trait(..) => tcx.resolve_lifetimes_trait_definition(local_def_id), - _ => tcx.resolve_lifetimes(local_def_id), - } - } else { - tcx.resolve_lifetimes(local_def_id) - } -} - -/// Finds the `Item` that contains the given `LocalDefId` -fn item_for(tcx: TyCtxt<'_>, local_def_id: LocalDefId) -> hir::ItemId { - match tcx.hir().find_by_def_id(local_def_id) { - Some(Node::Item(item)) => { - return item.item_id(); - } - _ => {} - } - let item = { - let hir_id = tcx.hir().local_def_id_to_hir_id(local_def_id); - let mut parent_iter = tcx.hir().parent_iter(hir_id); - loop { - let node = parent_iter.next().map(|n| n.1); - match node { - Some(hir::Node::Item(item)) => break item.item_id(), - Some(hir::Node::Crate(_)) | None => bug!("Called `item_for` on an Item."), - _ => {} - } - } - }; - item -} - fn late_region_as_bound_region<'tcx>(tcx: TyCtxt<'tcx>, region: &Region) -> ty::BoundVariableKind { match region { Region::LateBound(_, _, def_id) => { @@ -383,7 +293,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { let mut supertrait_lifetimes = vec![]; loop { match scope { - Scope::Body { .. } | Scope::Root => { + Scope::Body { .. } | Scope::Root { .. } => { break (vec![], BinderScopeType::Normal); } @@ -414,21 +324,12 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { } } impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { - type NestedFilter = nested_filter::All; + type NestedFilter = nested_filter::OnlyBodies; fn nested_visit_map(&mut self) -> Self::Map { self.tcx.hir() } - // We want to nest trait/impl items in their parent, but nothing else. - fn visit_nested_item(&mut self, _: hir::ItemId) {} - - fn visit_trait_item_ref(&mut self, ii: &'tcx hir::TraitItemRef) { - if !self.trait_definition_only { - intravisit::walk_trait_item_ref(self, ii) - } - } - fn visit_nested_body(&mut self, body: hir::BodyId) { let body = self.tcx.hir().body(body); self.with(Scope::Body { id: body.id(), s: self.scope }, |this| { @@ -491,7 +392,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .filter(|param| matches!(param.kind, GenericParamKind::Lifetime { .. })) .enumerate() .map(|(late_bound_idx, param)| { - let pair = Region::late(late_bound_idx as u32, self.tcx.hir(), param); + let pair = Region::late(late_bound_idx as u32, param); let r = late_region_as_bound_region(self.tcx, &pair.1); (pair, r) }) @@ -548,7 +449,9 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { intravisit::walk_item(this, item) }); } - hir::ItemKind::OpaqueTy(hir::OpaqueTy { .. }) => { + hir::ItemKind::OpaqueTy(hir::OpaqueTy { + origin: hir::OpaqueTyOrigin::TyAlias, .. + }) => { // Opaque types are visited when we visit the // `TyKind::OpaqueDef`, so that they have the lifetimes from // their parent opaque_ty in scope. @@ -557,34 +460,53 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { // their owner, we can keep going until we find the Item that owns that. We then // conservatively add all resolved lifetimes. Otherwise we run into problems in // cases like `type Foo<'a> = impl Bar<As = impl Baz + 'a>`. - for (_hir_id, node) in self.tcx.hir().parent_iter(item.owner_id.into()) { - match node { - hir::Node::Item(parent_item) => { - let resolved_lifetimes: &ResolveLifetimes = self.tcx.resolve_lifetimes( - item_for(self.tcx, parent_item.owner_id.def_id).owner_id.def_id, - ); - // We need to add *all* deps, since opaque tys may want them from *us* - for (&owner, defs) in resolved_lifetimes.defs.iter() { - defs.iter().for_each(|(&local_id, region)| { - self.map.defs.insert(hir::HirId { owner, local_id }, *region); - }); - } - for (&owner, late_bound_vars) in - resolved_lifetimes.late_bound_vars.iter() - { - late_bound_vars.iter().for_each(|(&local_id, late_bound_vars)| { - self.record_late_bound_vars( - hir::HirId { owner, local_id }, - late_bound_vars.clone(), - ); - }); - } - break; + let parent_item = self.tcx.hir().get_parent_item(item.hir_id()); + let resolved_lifetimes: &ResolveLifetimes = self.tcx.resolve_lifetimes(parent_item); + // We need to add *all* deps, since opaque tys may want them from *us* + for (&owner, defs) in resolved_lifetimes.defs.iter() { + defs.iter().for_each(|(&local_id, region)| { + self.map.defs.insert(hir::HirId { owner, local_id }, *region); + }); + } + for (&owner, late_bound_vars) in resolved_lifetimes.late_bound_vars.iter() { + late_bound_vars.iter().for_each(|(&local_id, late_bound_vars)| { + self.record_late_bound_vars( + hir::HirId { owner, local_id }, + late_bound_vars.clone(), + ); + }); + } + } + hir::ItemKind::OpaqueTy(hir::OpaqueTy { + origin: hir::OpaqueTyOrigin::FnReturn(_) | hir::OpaqueTyOrigin::AsyncFn(_), + generics, + .. + }) => { + // We want to start our early-bound indices at the end of the parent scope, + // not including any parent `impl Trait`s. + let mut lifetimes = FxIndexMap::default(); + debug!(?generics.params); + for param in generics.params { + match param.kind { + GenericParamKind::Lifetime { .. } => { + let (def_id, reg) = Region::early(¶m); + lifetimes.insert(def_id, reg); } - hir::Node::Crate(_) => bug!("No Item about an OpaqueTy"), - _ => {} + GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {} } } + + let scope = Scope::Binder { + hir_id: item.hir_id(), + lifetimes, + s: self.scope, + scope_type: BinderScopeType::Normal, + where_bound_origin: None, + }; + self.with(scope, |this| { + let scope = Scope::TraitRefBoundary { s: this.scope }; + this.with(scope, |this| intravisit::walk_item(this, item)) + }); } hir::ItemKind::TyAlias(_, ref generics) | hir::ItemKind::Enum(_, ref generics) @@ -598,9 +520,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .params .iter() .filter_map(|param| match param.kind { - GenericParamKind::Lifetime { .. } => { - Some(Region::early(self.tcx.hir(), param)) - } + GenericParamKind::Lifetime { .. } => Some(Region::early(param)), GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => None, }) .collect(); @@ -609,7 +529,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { hir_id: item.hir_id(), lifetimes, scope_type: BinderScopeType::Normal, - s: ROOT_SCOPE, + s: self.scope, where_bound_origin: None, }; self.with(scope, |this| { @@ -648,7 +568,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .filter(|param| matches!(param.kind, GenericParamKind::Lifetime { .. })) .enumerate() .map(|(late_bound_idx, param)| { - let pair = Region::late(late_bound_idx as u32, self.tcx.hir(), param); + let pair = Region::late(late_bound_idx as u32, param); let r = late_region_as_bound_region(self.tcx, &pair.1); (pair, r) }) @@ -675,7 +595,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { this.visit_poly_trait_ref(bound); } }); - match lifetime.name { + match lifetime.res { LifetimeName::ImplicitObjectLifetimeDefault => { // If the user does not write *anything*, we // use the object lifetime defaulting @@ -712,7 +632,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { // ^ ^ this gets resolved in the scope of // the opaque_ty generics let opaque_ty = self.tcx.hir().item(item_id); - let (generics, bounds) = match opaque_ty.kind { + match opaque_ty.kind { hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin: hir::OpaqueTyOrigin::TyAlias, .. @@ -733,10 +653,8 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { } hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin: hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..), - ref generics, - bounds, .. - }) => (generics, bounds), + }) => {} ref i => bug!("`impl Trait` pointed to non-opaque type?? {:#?}", i), }; @@ -766,65 +684,28 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { // Ensure that the parent of the def is an item, not HRTB let parent_id = self.tcx.hir().get_parent_node(hir_id); if !parent_id.is_owner() { - if !self.trait_definition_only { - struct_span_err!( - self.tcx.sess, - lifetime.span, - E0657, - "`impl Trait` can only capture lifetimes \ - bound at the fn or impl level" - ) - .emit(); - } + struct_span_err!( + self.tcx.sess, + lifetime.ident.span, + E0657, + "`impl Trait` can only capture lifetimes bound at the fn or impl level" + ) + .emit(); self.uninsert_lifetime_on_error(lifetime, def.unwrap()); } if let hir::Node::Item(hir::Item { kind: hir::ItemKind::OpaqueTy { .. }, .. }) = self.tcx.hir().get(parent_id) { - if !self.trait_definition_only { - let mut err = self.tcx.sess.struct_span_err( - lifetime.span, - "higher kinded lifetime bounds on nested opaque types are not supported yet", - ); - err.span_note(self.tcx.def_span(def_id), "lifetime declared here"); - err.emit(); - } + let mut err = self.tcx.sess.struct_span_err( + lifetime.ident.span, + "higher kinded lifetime bounds on nested opaque types are not supported yet", + ); + err.span_note(self.tcx.def_span(def_id), "lifetime declared here"); + err.emit(); self.uninsert_lifetime_on_error(lifetime, def.unwrap()); } } - - // We want to start our early-bound indices at the end of the parent scope, - // not including any parent `impl Trait`s. - let mut lifetimes = FxIndexMap::default(); - debug!(?generics.params); - for param in generics.params { - match param.kind { - GenericParamKind::Lifetime { .. } => { - let (def_id, reg) = Region::early(self.tcx.hir(), ¶m); - lifetimes.insert(def_id, reg); - } - GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {} - } - } - self.record_late_bound_vars(ty.hir_id, vec![]); - - let scope = Scope::Binder { - hir_id: ty.hir_id, - lifetimes, - s: self.scope, - scope_type: BinderScopeType::Normal, - where_bound_origin: None, - }; - self.with(scope, |this| { - let scope = Scope::TraitRefBoundary { s: this.scope }; - this.with(scope, |this| { - this.visit_generics(generics); - for bound in bounds { - this.visit_param_bound(bound); - } - }) - }); } _ => intravisit::walk_ty(self, ty), } @@ -845,9 +726,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .params .iter() .filter_map(|param| match param.kind { - GenericParamKind::Lifetime { .. } => { - Some(Region::early(self.tcx.hir(), param)) - } + GenericParamKind::Lifetime { .. } => Some(Region::early(param)), GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => None, }) .collect(); @@ -893,9 +772,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .params .iter() .filter_map(|param| match param.kind { - GenericParamKind::Lifetime { .. } => { - Some(Region::early(self.tcx.hir(), param)) - } + GenericParamKind::Lifetime { .. } => Some(Region::early(param)), GenericParamKind::Const { .. } | GenericParamKind::Type { .. } => None, }) .collect(); @@ -925,9 +802,9 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { #[instrument(level = "debug", skip(self))] fn visit_lifetime(&mut self, lifetime_ref: &'tcx hir::Lifetime) { - match lifetime_ref.name { + match lifetime_ref.res { hir::LifetimeName::Static => self.insert_lifetime(lifetime_ref, Region::Static), - hir::LifetimeName::Param(param_def_id, _) => { + hir::LifetimeName::Param(param_def_id) => { self.resolve_lifetime_ref(param_def_id, lifetime_ref) } // If we've already reported an error, just ignore `lifetime_ref`. @@ -937,7 +814,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { } } - fn visit_path(&mut self, path: &'tcx hir::Path<'tcx>, _: hir::HirId) { + fn visit_path(&mut self, path: &hir::Path<'tcx>, _: hir::HirId) { for (i, segment) in path.segments.iter().enumerate() { let depth = path.segments.len() - i - 1; if let Some(ref args) = segment.args { @@ -1000,7 +877,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { }) .enumerate() .map(|(late_bound_idx, param)| { - Region::late(late_bound_idx as u32, this.tcx.hir(), param) + Region::late(late_bound_idx as u32, param) }) .collect(); let binders: Vec<_> = @@ -1035,27 +912,27 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { this.visit_lifetime(lifetime); walk_list!(this, visit_param_bound, bounds); - if lifetime.name != hir::LifetimeName::Static { + if lifetime.res != hir::LifetimeName::Static { for bound in bounds { let hir::GenericBound::Outlives(ref lt) = bound else { continue; }; - if lt.name != hir::LifetimeName::Static { + if lt.res != hir::LifetimeName::Static { continue; } this.insert_lifetime(lt, Region::Static); this.tcx .sess .struct_span_warn( - lifetime.span, + lifetime.ident.span, &format!( "unnecessary lifetime parameter `{}`", - lifetime.name.ident(), + lifetime.ident, ), ) .help(&format!( "you can use the `'static` lifetime directly, in place of `{}`", - lifetime.name.ident(), + lifetime.ident, )) .emit(); } @@ -1113,8 +990,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { .filter(|param| matches!(param.kind, GenericParamKind::Lifetime { .. })) .enumerate() .map(|(late_bound_idx, param)| { - let pair = - Region::late(initial_bound_vars + late_bound_idx as u32, self.tcx.hir(), param); + let pair = Region::late(initial_bound_vars + late_bound_idx as u32, param); let r = late_region_as_bound_region(self.tcx, &pair.1); lifetimes.insert(pair.0, pair.1); r @@ -1167,7 +1043,7 @@ fn object_lifetime_default<'tcx>(tcx: TyCtxt<'tcx>, param_def_id: DefId) -> Obje for bound in bound.bounds { if let hir::GenericBound::Outlives(ref lifetime) = *bound { - set.insert(lifetime.name.normalize_to_macros_2_0()); + set.insert(lifetime.res); } } } @@ -1175,7 +1051,7 @@ fn object_lifetime_default<'tcx>(tcx: TyCtxt<'tcx>, param_def_id: DefId) -> Obje match set { Set1::Empty => ObjectLifetimeDefault::Empty, Set1::One(hir::LifetimeName::Static) => ObjectLifetimeDefault::Static, - Set1::One(hir::LifetimeName::Param(param_def_id, _)) => { + Set1::One(hir::LifetimeName::Param(param_def_id)) => { ObjectLifetimeDefault::Param(param_def_id.to_def_id()) } _ => ObjectLifetimeDefault::Ambiguous, @@ -1193,12 +1069,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { F: for<'b> FnOnce(&mut LifetimeContext<'b, 'tcx>), { let LifetimeContext { tcx, map, .. } = self; - let mut this = LifetimeContext { - tcx: *tcx, - map, - scope: &wrap_scope, - trait_definition_only: self.trait_definition_only, - }; + let mut this = LifetimeContext { tcx: *tcx, map, scope: &wrap_scope }; let span = debug_span!("scope", scope = ?TruncatedScopeDebug(&this.scope)); { let _enter = span.enter(); @@ -1250,9 +1121,9 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { if self.tcx.is_late_bound(param.hir_id) { let late_bound_idx = named_late_bound_vars; named_late_bound_vars += 1; - Some(Region::late(late_bound_idx, self.tcx.hir(), param)) + Some(Region::late(late_bound_idx, param)) } else { - Some(Region::early(self.tcx.hir(), param)) + Some(Region::early(param)) } } GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => None, @@ -1268,7 +1139,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { }) .enumerate() .map(|(late_bound_idx, param)| { - let pair = Region::late(late_bound_idx as u32, self.tcx.hir(), param); + let pair = Region::late(late_bound_idx as u32, param); late_region_as_bound_region(self.tcx, &pair.1) }) .collect(); @@ -1303,7 +1174,13 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { scope = s; } - Scope::Root => { + Scope::Root { opt_parent_item } => { + if let Some(parent_item) = opt_parent_item + && let parent_generics = self.tcx.generics_of(parent_item) + && parent_generics.param_def_id_to_index.contains_key(®ion_def_id.to_def_id()) + { + break Some(Region::EarlyBound(region_def_id.to_def_id())); + } break None; } @@ -1318,42 +1195,52 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { // Fresh lifetimes in APIT used to be allowed in async fns and forbidden in // regular fns. if let Some(hir::PredicateOrigin::ImplTrait) = where_bound_origin - && let hir::LifetimeName::Param(_, hir::ParamName::Fresh) = lifetime_ref.name + && let hir::LifetimeName::Param(param_id) = lifetime_ref.res + && let Some(generics) = self.tcx.hir().get_generics(self.tcx.local_parent(param_id)) + && let Some(param) = generics.params.iter().find(|p| p.def_id == param_id) + && param.is_elided_lifetime() && let hir::IsAsync::NotAsync = self.tcx.asyncness(lifetime_ref.hir_id.owner.def_id) && !self.tcx.features().anonymous_lifetime_in_impl_trait { let mut diag = rustc_session::parse::feature_err( &self.tcx.sess.parse_sess, sym::anonymous_lifetime_in_impl_trait, - lifetime_ref.span, + lifetime_ref.ident.span, "anonymous lifetimes in `impl Trait` are unstable", ); - match self.tcx.hir().get_generics(lifetime_ref.hir_id.owner.def_id) { - Some(generics) => { - - let new_param_sugg_tuple; - - new_param_sugg_tuple = match generics.span_for_param_suggestion() { - Some(_) => { - Some((self.tcx.sess.source_map().span_through_char(generics.span, '<').shrink_to_hi(), "'a, ".to_owned())) - }, - None => Some((generics.span, "<'a>".to_owned())) - }; - - let mut multi_sugg_vec = vec![(lifetime_ref.span.shrink_to_hi(), "'a ".to_owned())]; - - if let Some(new_tuple) = new_param_sugg_tuple{ - multi_sugg_vec.push(new_tuple); - } - - diag.span_label(lifetime_ref.span, "expected named lifetime parameter"); - diag.multipart_suggestion("consider introducing a named lifetime parameter", - multi_sugg_vec, - rustc_errors::Applicability::MaybeIncorrect); - - }, - None => { } + if let Some(generics) = + self.tcx.hir().get_generics(lifetime_ref.hir_id.owner.def_id) + { + let new_param_sugg = if let Some(span) = + generics.span_for_lifetime_suggestion() + { + (span, "'a, ".to_owned()) + } else { + (generics.span, "<'a>".to_owned()) + }; + + let lifetime_sugg = match lifetime_ref.suggestion_position() { + (hir::LifetimeSuggestionPosition::Normal, span) => (span, "'a".to_owned()), + (hir::LifetimeSuggestionPosition::Ampersand, span) => (span, "'a ".to_owned()), + (hir::LifetimeSuggestionPosition::ElidedPath, span) => (span, "<'a>".to_owned()), + (hir::LifetimeSuggestionPosition::ElidedPathArgument, span) => (span, "'a, ".to_owned()), + (hir::LifetimeSuggestionPosition::ObjectDefault, span) => (span, "+ 'a".to_owned()), + }; + let suggestions = vec![ + lifetime_sugg, + new_param_sugg, + ]; + + diag.span_label( + lifetime_ref.ident.span, + "expected named lifetime parameter", + ); + diag.multipart_suggestion( + "consider introducing a named lifetime parameter", + suggestions, + rustc_errors::Applicability::MaybeIncorrect, + ); } diag.emit(); @@ -1377,11 +1264,12 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { } else if let Some(body_id) = outermost_body { let fn_id = self.tcx.hir().body_owner(body_id); match self.tcx.hir().get(fn_id) { - Node::Item(&hir::Item { kind: hir::ItemKind::Fn(..), .. }) - | Node::TraitItem(&hir::TraitItem { + Node::Item(hir::Item { kind: hir::ItemKind::Fn(..), .. }) + | Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Fn(..), .. }) - | Node::ImplItem(&hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }) => { + | Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }) + | Node::Expr(hir::Expr { kind: hir::ExprKind::Closure(..), .. }) => { let scope = self.tcx.hir().local_def_id(fn_id); def = Region::Free(scope.to_def_id(), def.id().unwrap()); } @@ -1409,14 +1297,14 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { where_bound_origin: Some(hir::PredicateOrigin::ImplTrait), .. } => { let mut err = self.tcx.sess.struct_span_err( - lifetime_ref.span, + lifetime_ref.ident.span, "`impl Trait` can only mention lifetimes bound at the fn or impl level", ); err.span_note(self.tcx.def_span(region_def_id), "lifetime declared here"); err.emit(); return; } - Scope::Root => break, + Scope::Root { .. } => break, Scope::Binder { s, .. } | Scope::Body { s, .. } | Scope::Elision { s, .. } @@ -1429,7 +1317,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { } self.tcx.sess.delay_span_bug( - lifetime_ref.span, + lifetime_ref.ident.span, &format!("Could not resolve {:?} in scope {:#?}", lifetime_ref, self.scope,), ); } @@ -1494,7 +1382,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { let mut scope = self.scope; loop { match *scope { - Scope::Root => break false, + Scope::Root { .. } => break false, Scope::Body { .. } => break true, @@ -1680,7 +1568,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { let obligations = predicates.predicates.iter().filter_map(|&(pred, _)| { let bound_predicate = pred.kind(); match bound_predicate.skip_binder() { - ty::PredicateKind::Trait(data) => { + ty::PredicateKind::Clause(ty::Clause::Trait(data)) => { // The order here needs to match what we would get from `subst_supertrait` let pred_bound_vars = bound_predicate.bound_vars(); let mut all_bound_vars = bound_vars.clone(); @@ -1731,7 +1619,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { scope = s; } - Scope::Root | Scope::Elision { .. } => break Region::Static, + Scope::Root { .. } | Scope::Elision { .. } => break Region::Static, Scope::Body { .. } | Scope::ObjectLifetimeDefault { lifetime: None, .. } => return, @@ -1747,10 +1635,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { #[instrument(level = "debug", skip(self))] fn insert_lifetime(&mut self, lifetime_ref: &'tcx hir::Lifetime, def: Region) { - debug!( - node = ?self.tcx.hir().node_to_string(lifetime_ref.hir_id), - span = ?self.tcx.sess.source_map().span_to_diagnostic_string(lifetime_ref.span) - ); + debug!(span = ?lifetime_ref.ident.span); self.map.defs.insert(lifetime_ref.hir_id, def); } @@ -1780,7 +1665,7 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet< let mut late_bound = FxIndexSet::default(); - let mut constrained_by_input = ConstrainedCollector::default(); + let mut constrained_by_input = ConstrainedCollector { regions: Default::default(), tcx }; for arg_ty in decl.inputs { constrained_by_input.visit_ty(arg_ty); } @@ -1833,12 +1718,65 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet< debug!(?late_bound); return Some(tcx.arena.alloc(late_bound)); - #[derive(Default)] - struct ConstrainedCollector { + /// Visits a `ty::Ty` collecting information about what generic parameters are constrained. + /// + /// The visitor does not operate on `hir::Ty` so that it can be called on the rhs of a `type Alias<...> = ...;` + /// which may live in a separate crate so there would not be any hir available. Instead we use the `type_of` + /// query to obtain a `ty::Ty` which will be present even in cross crate scenarios. It also naturally + /// handles cycle detection as we go through the query system. + /// + /// This is necessary in the first place for the following case: + /// ``` + /// type Alias<'a, T> = <T as Trait<'a>>::Assoc; + /// fn foo<'a>(_: Alias<'a, ()>) -> Alias<'a, ()> { ... } + /// ``` + /// + /// If we conservatively considered `'a` unconstrained then we could break users who had written code before + /// we started correctly handling aliases. If we considered `'a` constrained then it would become late bound + /// causing an error during astconv as the `'a` is not constrained by the input type `<() as Trait<'a>>::Assoc` + /// but appears in the output type `<() as Trait<'a>>::Assoc`. + /// + /// We must therefore "look into" the `Alias` to see whether we should consider `'a` constrained or not. + /// + /// See #100508 #85533 #47511 for additional context + struct ConstrainedCollectorPostAstConv { + arg_is_constrained: Box<[bool]>, + } + + use std::ops::ControlFlow; + use ty::Ty; + impl<'tcx> TypeVisitor<'tcx> for ConstrainedCollectorPostAstConv { + fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<!> { + match t.kind() { + ty::Param(param_ty) => { + self.arg_is_constrained[param_ty.index as usize] = true; + } + ty::Projection(_) => return ControlFlow::Continue(()), + _ => (), + } + t.super_visit_with(self) + } + + fn visit_const(&mut self, _: ty::Const<'tcx>) -> ControlFlow<!> { + ControlFlow::Continue(()) + } + + fn visit_region(&mut self, r: ty::Region<'tcx>) -> ControlFlow<!> { + debug!("r={:?}", r.kind()); + if let ty::RegionKind::ReEarlyBound(region) = r.kind() { + self.arg_is_constrained[region.index as usize] = true; + } + + ControlFlow::Continue(()) + } + } + + struct ConstrainedCollector<'tcx> { + tcx: TyCtxt<'tcx>, regions: FxHashSet<LocalDefId>, } - impl<'v> Visitor<'v> for ConstrainedCollector { + impl<'v> Visitor<'v> for ConstrainedCollector<'_> { fn visit_ty(&mut self, ty: &'v hir::Ty<'v>) { match ty.kind { hir::TyKind::Path( @@ -1849,6 +1787,47 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet< // (defined above) } + hir::TyKind::Path(hir::QPath::Resolved( + None, + hir::Path { res: Res::Def(DefKind::TyAlias, alias_def), segments, span }, + )) => { + // See comments on `ConstrainedCollectorPostAstConv` for why this arm does not just consider + // substs to be unconstrained. + let generics = self.tcx.generics_of(alias_def); + let mut walker = ConstrainedCollectorPostAstConv { + arg_is_constrained: vec![false; generics.params.len()].into_boxed_slice(), + }; + walker.visit_ty(self.tcx.type_of(alias_def)); + + match segments.last() { + Some(hir::PathSegment { args: Some(args), .. }) => { + let tcx = self.tcx; + for constrained_arg in + args.args.iter().enumerate().flat_map(|(n, arg)| { + match walker.arg_is_constrained.get(n) { + Some(true) => Some(arg), + Some(false) => None, + None => { + tcx.sess.delay_span_bug( + *span, + format!( + "Incorrect generic arg count for alias {:?}", + alias_def + ), + ); + None + } + } + }) + { + self.visit_generic_arg(constrained_arg); + } + } + Some(_) => (), + None => bug!("Path with no segments or self type"), + } + } + hir::TyKind::Path(hir::QPath::Resolved(None, ref path)) => { // consider only the lifetimes on the final // segment; I am not sure it's even currently @@ -1867,7 +1846,7 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet< } fn visit_lifetime(&mut self, lifetime_ref: &'v hir::Lifetime) { - if let hir::LifetimeName::Param(def_id, _) = lifetime_ref.name { + if let hir::LifetimeName::Param(def_id) = lifetime_ref.res { self.regions.insert(def_id); } } @@ -1880,7 +1859,7 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet< impl<'v> Visitor<'v> for AllCollector { fn visit_lifetime(&mut self, lifetime_ref: &'v hir::Lifetime) { - if let hir::LifetimeName::Param(def_id, _) = lifetime_ref.name { + if let hir::LifetimeName::Param(def_id) = lifetime_ref.res { self.regions.insert(def_id); } } diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs index 2e84e1d01..45e241f4e 100644 --- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs @@ -84,60 +84,30 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP Node::ImplItem(item) => item.generics, - Node::Item(item) => { - match item.kind { - ItemKind::Impl(ref impl_) => { - if impl_.defaultness.is_default() { - is_default_impl_trait = tcx.impl_trait_ref(def_id).map(ty::Binder::dummy); - } - &impl_.generics - } - ItemKind::Fn(.., ref generics, _) - | ItemKind::TyAlias(_, ref generics) - | ItemKind::Enum(_, ref generics) - | ItemKind::Struct(_, ref generics) - | ItemKind::Union(_, ref generics) => *generics, - - ItemKind::Trait(_, _, ref generics, ..) => { - is_trait = Some(ty::TraitRef::identity(tcx, def_id)); - *generics + Node::Item(item) => match item.kind { + ItemKind::Impl(ref impl_) => { + if impl_.defaultness.is_default() { + is_default_impl_trait = tcx.impl_trait_ref(def_id).map(ty::Binder::dummy); } - ItemKind::TraitAlias(ref generics, _) => { - is_trait = Some(ty::TraitRef::identity(tcx, def_id)); - *generics - } - ItemKind::OpaqueTy(OpaqueTy { - origin: hir::OpaqueTyOrigin::AsyncFn(..) | hir::OpaqueTyOrigin::FnReturn(..), - .. - }) => { - // return-position impl trait - // - // We don't inherit predicates from the parent here: - // If we have, say `fn f<'a, T: 'a>() -> impl Sized {}` - // then the return type is `f::<'static, T>::{{opaque}}`. - // - // If we inherited the predicates of `f` then we would - // require that `T: 'static` to show that the return - // type is well-formed. - // - // The only way to have something with this opaque type - // is from the return type of the containing function, - // which will ensure that the function's predicates - // hold. - return ty::GenericPredicates { parent: None, predicates: &[] }; - } - ItemKind::OpaqueTy(OpaqueTy { - ref generics, - origin: hir::OpaqueTyOrigin::TyAlias, - .. - }) => { - // type-alias impl trait - generics - } - - _ => NO_GENERICS, + &impl_.generics } - } + ItemKind::Fn(.., ref generics, _) + | ItemKind::TyAlias(_, ref generics) + | ItemKind::Enum(_, ref generics) + | ItemKind::Struct(_, ref generics) + | ItemKind::Union(_, ref generics) => *generics, + + ItemKind::Trait(_, _, ref generics, ..) => { + is_trait = Some(ty::TraitRef::identity(tcx, def_id)); + *generics + } + ItemKind::TraitAlias(ref generics, _) => { + is_trait = Some(ty::TraitRef::identity(tcx, def_id)); + *generics + } + ItemKind::OpaqueTy(OpaqueTy { ref generics, .. }) => generics, + _ => NO_GENERICS, + }, Node::ForeignItem(item) => match item.kind { ForeignItemKind::Static(..) => NO_GENERICS, @@ -181,6 +151,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP trace!(?predicates); trace!(?ast_generics); + trace!(?generics); // Collect the predicates that were written inline by the user on each // type parameter (e.g., `<T: Foo>`). @@ -199,7 +170,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP &icx, &mut bounds, &[], - Some((param.hir_id, ast_generics.predicates)), + Some((param.def_id, ast_generics.predicates)), param.span, ); trace!(?bounds); @@ -258,12 +229,12 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP predicates.extend(region_pred.bounds.iter().map(|bound| { let (r2, span) = match bound { hir::GenericBound::Outlives(lt) => { - (<dyn AstConv<'_>>::ast_region_to_region(&icx, lt, None), lt.span) + (<dyn AstConv<'_>>::ast_region_to_region(&icx, lt, None), lt.ident.span) } _ => bug!(), }; - let pred = ty::Binder::dummy(ty::PredicateKind::RegionOutlives( - ty::OutlivesPredicate(r1, r2), + let pred = ty::Binder::dummy(ty::PredicateKind::Clause( + ty::Clause::RegionOutlives(ty::OutlivesPredicate(r1, r2)), )) .to_predicate(icx.tcx); @@ -299,6 +270,52 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP ); } + // Opaque types duplicate some of their generic parameters. + // We create bi-directional Outlives predicates between the original + // and the duplicated parameter, to ensure that they do not get out of sync. + if let Node::Item(&Item { kind: ItemKind::OpaqueTy(..), .. }) = node { + let opaque_ty_id = tcx.hir().get_parent_node(hir_id); + let opaque_ty_node = tcx.hir().get(opaque_ty_id); + let Node::Ty(&Ty { kind: TyKind::OpaqueDef(_, lifetimes, _), .. }) = opaque_ty_node else { + bug!("unexpected {opaque_ty_node:?}") + }; + debug!(?lifetimes); + for (arg, duplicate) in std::iter::zip(lifetimes, ast_generics.params) { + let hir::GenericArg::Lifetime(arg) = arg else { bug!() }; + let orig_region = <dyn AstConv<'_>>::ast_region_to_region(&icx, &arg, None); + if !matches!(orig_region.kind(), ty::ReEarlyBound(..)) { + // Only early-bound regions can point to the original generic parameter. + continue; + } + + let hir::GenericParamKind::Lifetime { .. } = duplicate.kind else { continue }; + let dup_def = tcx.hir().local_def_id(duplicate.hir_id).to_def_id(); + + let Some(dup_index) = generics.param_def_id_to_index(tcx, dup_def) else { bug!() }; + + let dup_region = tcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion { + def_id: dup_def, + index: dup_index, + name: duplicate.name.ident().name, + })); + predicates.push(( + ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::RegionOutlives( + ty::OutlivesPredicate(orig_region, dup_region), + ))) + .to_predicate(icx.tcx), + duplicate.span, + )); + predicates.push(( + ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::RegionOutlives( + ty::OutlivesPredicate(dup_region, orig_region), + ))) + .to_predicate(icx.tcx), + duplicate.span, + )); + } + debug!(?predicates); + } + ty::GenericPredicates { parent: generics.parent, predicates: tcx.arena.alloc_from_iter(predicates), @@ -316,10 +333,9 @@ fn const_evaluatable_predicates_of<'tcx>( impl<'tcx> intravisit::Visitor<'tcx> for ConstCollector<'tcx> { fn visit_anon_const(&mut self, c: &'tcx hir::AnonConst) { - let def_id = self.tcx.hir().local_def_id(c.hir_id); - let ct = ty::Const::from_anon_const(self.tcx, def_id); + let ct = ty::Const::from_anon_const(self.tcx, c.def_id); if let ty::ConstKind::Unevaluated(_) = ct.kind() { - let span = self.tcx.hir().span(c.hir_id); + let span = self.tcx.def_span(c.def_id); self.preds.insert(( ty::Binder::dummy(ty::PredicateKind::ConstEvaluatable(ct)) .to_predicate(self.tcx), @@ -408,11 +424,13 @@ pub(super) fn explicit_predicates_of<'tcx>( .iter() .copied() .filter(|(pred, _)| match pred.kind().skip_binder() { - ty::PredicateKind::Trait(tr) => !is_assoc_item_ty(tr.self_ty()), - ty::PredicateKind::Projection(proj) => { + ty::PredicateKind::Clause(ty::Clause::Trait(tr)) => !is_assoc_item_ty(tr.self_ty()), + ty::PredicateKind::Clause(ty::Clause::Projection(proj)) => { !is_assoc_item_ty(proj.projection_ty.self_ty()) } - ty::PredicateKind::TypeOutlives(outlives) => !is_assoc_item_ty(outlives.0), + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(outlives)) => { + !is_assoc_item_ty(outlives.0) + } _ => true, }) .collect(); @@ -427,7 +445,9 @@ pub(super) fn explicit_predicates_of<'tcx>( } else { if matches!(def_kind, DefKind::AnonConst) && tcx.lazy_normalization() { let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local()); - if tcx.hir().opt_const_param_default_param_hir_id(hir_id).is_some() { + let parent_def_id = tcx.hir().get_parent_item(hir_id); + + if tcx.hir().opt_const_param_default_param_def_id(hir_id).is_some() { // In `generics_of` we set the generics' parent to be our parent's parent which means that // we lose out on the predicates of our actual parent if we dont return those predicates here. // (See comment in `generics_of` for more information on why the parent shenanigans is necessary) @@ -439,8 +459,33 @@ pub(super) fn explicit_predicates_of<'tcx>( // parent of generics returned by `generics_of` // // In the above code we want the anon const to have predicates in its param env for `T: Trait` - let item_def_id = tcx.hir().get_parent_item(hir_id); - // In the above code example we would be calling `explicit_predicates_of(Foo)` here + // and we would be calling `explicit_predicates_of(Foo)` here + return tcx.explicit_predicates_of(parent_def_id); + } + + let parent_def_kind = tcx.def_kind(parent_def_id); + if matches!(parent_def_kind, DefKind::OpaqueTy) { + // In `instantiate_identity` we inherit the predicates of our parent. + // However, opaque types do not have a parent (see `gather_explicit_predicates_of`), which means + // that we lose out on the predicates of our actual parent if we dont return those predicates here. + // + // + // fn foo<T: Trait>() -> impl Iterator<Output = Another<{ <T as Trait>::ASSOC }> > { todo!() } + // ^^^^^^^^^^^^^^^^^^^ the def id we are calling + // explicit_predicates_of on + // + // In the above code we want the anon const to have predicates in its param env for `T: Trait`. + // However, the anon const cannot inherit predicates from its parent since it's opaque. + // + // To fix this, we call `explicit_predicates_of` directly on `foo`, the parent's parent. + + // In the above example this is `foo::{opaque#0}` or `impl Iterator` + let parent_hir_id = tcx.hir().local_def_id_to_hir_id(parent_def_id.def_id); + + // In the above example this is the function `foo` + let item_def_id = tcx.hir().get_parent_item(parent_hir_id); + + // In the above code example we would be calling `explicit_predicates_of(foo)` here return tcx.explicit_predicates_of(item_def_id); } } @@ -504,7 +549,7 @@ pub(super) fn super_predicates_that_define_assoc_type( let is_trait_alias = tcx.is_trait_alias(trait_def_id); let superbounds2 = icx.type_parameter_bounds_in_generics( generics, - item.hir_id(), + item.owner_id.def_id, self_param_ty, OnlySelfBounds(!is_trait_alias), assoc_name, @@ -521,7 +566,9 @@ pub(super) fn super_predicates_that_define_assoc_type( // which will, in turn, reach indirect supertraits. for &(pred, span) in superbounds { debug!("superbound: {:?}", pred); - if let ty::PredicateKind::Trait(bound) = pred.kind().skip_binder() { + if let ty::PredicateKind::Clause(ty::Clause::Trait(bound)) = + pred.kind().skip_binder() + { tcx.at(span).super_predicates_of(bound.def_id()); } } @@ -614,14 +661,14 @@ pub(super) fn type_param_predicates( let extra_predicates = extend.into_iter().chain( icx.type_parameter_bounds_in_generics( ast_generics, - param_id, + def_id, ty, OnlySelfBounds(true), Some(assoc_name), ) .into_iter() .filter(|(predicate, _)| match predicate.kind().skip_binder() { - ty::PredicateKind::Trait(data) => data.self_ty().is_param(index), + ty::PredicateKind::Clause(ty::Clause::Trait(data)) => data.self_ty().is_param(index), _ => false, }), ); @@ -639,13 +686,11 @@ impl<'tcx> ItemCtxt<'tcx> { fn type_parameter_bounds_in_generics( &self, ast_generics: &'tcx hir::Generics<'tcx>, - param_id: hir::HirId, + param_def_id: LocalDefId, ty: Ty<'tcx>, only_self_bounds: OnlySelfBounds, assoc_name: Option<Ident>, ) -> Vec<(ty::Predicate<'tcx>, Span)> { - let param_def_id = self.tcx.hir().local_def_id(param_id).to_def_id(); - trace!(?param_def_id); ast_generics .predicates .iter() @@ -654,7 +699,7 @@ impl<'tcx> ItemCtxt<'tcx> { _ => None, }) .flat_map(|bp| { - let bt = if bp.is_param_bound(param_def_id) { + let bt = if bp.is_param_bound(param_def_id.to_def_id()) { Some(ty) } else if !only_self_bounds.0 { Some(self.to_ty(bp.bounded_ty)) diff --git a/compiler/rustc_hir_analysis/src/collect/type_of.rs b/compiler/rustc_hir_analysis/src/collect/type_of.rs index c29a645eb..9bd1715ce 100644 --- a/compiler/rustc_hir_analysis/src/collect/type_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/type_of.rs @@ -514,10 +514,10 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { } Node::GenericParam(&GenericParam { - hir_id: param_hir_id, + def_id: param_def_id, kind: GenericParamKind::Const { default: Some(ct), .. }, .. - }) if ct.hir_id == hir_id => tcx.type_of(tcx.hir().local_def_id(param_hir_id)), + }) if ct.hir_id == hir_id => tcx.type_of(param_def_id), x => tcx.ty_error_with_message( DUMMY_SP, @@ -636,9 +636,8 @@ fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> T self.tcx.hir() } fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) { - if let hir::ExprKind::Closure { .. } = ex.kind { - let def_id = self.tcx.hir().local_def_id(ex.hir_id); - self.check(def_id); + if let hir::ExprKind::Closure(closure) = ex.kind { + self.check(closure.def_id); } intravisit::walk_expr(self, ex); } @@ -698,7 +697,7 @@ fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> T } let Some(hidden) = locator.found else { - tcx.sess.emit_err(UnconstrainedOpaqueType { + let reported = tcx.sess.emit_err(UnconstrainedOpaqueType { span: tcx.def_span(def_id), name: tcx.item_name(tcx.local_parent(def_id).to_def_id()), what: match tcx.hir().get(scope) { @@ -708,7 +707,7 @@ fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> T _ => "item", }, }); - return tcx.ty_error(); + return tcx.ty_error_with_guaranteed(reported); }; // Only check against typeck if we didn't already error @@ -771,9 +770,8 @@ fn find_opaque_ty_constraints_for_rpit( self.tcx.hir() } fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) { - if let hir::ExprKind::Closure { .. } = ex.kind { - let def_id = self.tcx.hir().local_def_id(ex.hir_id); - self.check(def_id); + if let hir::ExprKind::Closure(closure) = ex.kind { + self.check(closure.def_id); } intravisit::walk_expr(self, ex); } diff --git a/compiler/rustc_hir_analysis/src/constrained_generic_params.rs b/compiler/rustc_hir_analysis/src/constrained_generic_params.rs index 213b89fc7..b4057df78 100644 --- a/compiler/rustc_hir_analysis/src/constrained_generic_params.rs +++ b/compiler/rustc_hir_analysis/src/constrained_generic_params.rs @@ -187,7 +187,8 @@ pub fn setup_constraining_predicates<'tcx>( for j in i..predicates.len() { // Note that we don't have to care about binders here, // as the impl trait ref never contains any late-bound regions. - if let ty::PredicateKind::Projection(projection) = predicates[j].0.kind().skip_binder() + if let ty::PredicateKind::Clause(ty::Clause::Projection(projection)) = + predicates[j].0.kind().skip_binder() { // Special case: watch out for some kind of sneaky attempt // to project out an associated type defined by this very diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs index d5b1a7ce1..c92ab749b 100644 --- a/compiler/rustc_hir_analysis/src/errors.rs +++ b/compiler/rustc_hir_analysis/src/errors.rs @@ -43,6 +43,10 @@ pub struct LifetimesOrBoundsMismatchOnTrait { pub span: Span, #[label(generics_label)] pub generics_span: Option<Span>, + #[label(where_label)] + pub where_span: Option<Span>, + #[label(bounds_label)] + pub bounds_span: Vec<Span>, pub item_kind: &'static str, pub ident: Ident, } @@ -120,7 +124,7 @@ pub struct TypeofReservedKeywordUsed<'tcx> { #[primary_span] #[label] pub span: Span, - #[suggestion_verbose(code = "{ty}")] + #[suggestion(style = "verbose", code = "{ty}")] pub opt_sugg: Option<(Span, Applicability)>, } @@ -156,6 +160,7 @@ pub struct MissingTypeParams { // Manual implementation of `IntoDiagnostic` to be able to call `span_to_snippet`. impl<'a> IntoDiagnostic<'a> for MissingTypeParams { + #[track_caller] fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, ErrorGuaranteed> { let mut err = handler.struct_span_err_with_code( self.span, @@ -238,7 +243,11 @@ pub struct UnusedExternCrate { #[derive(LintDiagnostic)] #[diag(hir_analysis_extern_crate_not_idiomatic)] pub struct ExternCrateNotIdiomatic { - #[suggestion_short(applicability = "machine-applicable", code = "{suggestion_code}")] + #[suggestion( + style = "short", + applicability = "machine-applicable", + code = "{suggestion_code}" + )] pub span: Span, pub msg_code: String, pub suggestion_code: String, @@ -280,3 +289,10 @@ pub struct SelfInImplSelf { #[note] pub note: (), } + +#[derive(Diagnostic)] +#[diag(hir_analysis_linkage_type, code = "E0791")] +pub(crate) struct LinkageType { + #[primary_span] + pub span: Span, +} diff --git a/compiler/rustc_hir_analysis/src/hir_wf_check.rs b/compiler/rustc_hir_analysis/src/hir_wf_check.rs index b0fdfcf38..4f9d58265 100644 --- a/compiler/rustc_hir_analysis/src/hir_wf_check.rs +++ b/compiler/rustc_hir_analysis/src/hir_wf_check.rs @@ -5,7 +5,7 @@ use rustc_hir::{ForeignItem, ForeignItemKind, HirId}; use rustc_infer::infer::TyCtxtInferExt; use rustc_infer::traits::{ObligationCause, WellFormedLoc}; use rustc_middle::ty::query::Providers; -use rustc_middle::ty::{self, Region, ToPredicate, TyCtxt, TypeFoldable, TypeFolder}; +use rustc_middle::ty::{self, Region, TyCtxt, TypeFoldable, TypeFolder}; use rustc_trait_selection::traits; pub fn provide(providers: &mut Providers) { @@ -74,10 +74,10 @@ fn diagnostic_hir_wf_check<'tcx>( let errors = traits::fully_solve_obligation( &infcx, traits::Obligation::new( + self.tcx, cause, self.param_env, - ty::Binder::dummy(ty::PredicateKind::WellFormed(tcx_ty.into())) - .to_predicate(self.tcx), + ty::Binder::dummy(ty::PredicateKind::WellFormed(tcx_ty.into())), ), ); if !errors.is_empty() { diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs index e806e9487..fd8e8ed7b 100644 --- a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs +++ b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs @@ -69,6 +69,7 @@ use crate::constrained_generic_params as cgp; use crate::errors::SubstsOnOverriddenImpl; use rustc_data_structures::fx::FxHashSet; +use rustc_hir as hir; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::TyCtxtInferExt; @@ -80,6 +81,7 @@ use rustc_span::Span; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _; use rustc_trait_selection::traits::{self, translate_substs, wf, ObligationCtxt}; +use tracing::instrument; pub(super) fn check_min_specialization(tcx: TyCtxt<'_>, impl_def_id: LocalDefId) { if let Some(node) = parent_specialization_node(tcx, impl_def_id) { @@ -103,13 +105,11 @@ fn parent_specialization_node(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId) -> Opti } /// Check that `impl1` is a sound specialization +#[instrument(level = "debug", skip(tcx))] fn check_always_applicable(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node: Node) { if let Some((impl1_substs, impl2_substs)) = get_impl_substs(tcx, impl1_def_id, impl2_node) { let impl2_def_id = impl2_node.def_id(); - debug!( - "check_always_applicable(\nimpl1_def_id={:?},\nimpl2_def_id={:?},\nimpl2_substs={:?}\n)", - impl1_def_id, impl2_def_id, impl2_substs - ); + debug!(?impl2_def_id, ?impl2_substs); let parent_substs = if impl2_node.is_from_trait() { impl2_substs.to_vec() @@ -118,12 +118,33 @@ fn check_always_applicable(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node }; let span = tcx.def_span(impl1_def_id); + check_constness(tcx, impl1_def_id, impl2_node, span); check_static_lifetimes(tcx, &parent_substs, span); check_duplicate_params(tcx, impl1_substs, &parent_substs, span); check_predicates(tcx, impl1_def_id, impl1_substs, impl2_node, impl2_substs, span); } } +/// Check that the specializing impl `impl1` is at least as const as the base +/// impl `impl2` +fn check_constness(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node: Node, span: Span) { + if impl2_node.is_from_trait() { + // This isn't a specialization + return; + } + + let impl1_constness = tcx.constness(impl1_def_id.to_def_id()); + let impl2_constness = tcx.constness(impl2_node.def_id()); + + if let hir::Constness::Const = impl2_constness { + if let hir::Constness::NotConst = impl1_constness { + tcx.sess + .struct_span_err(span, "cannot specialize on const impl with non-const impl") + .emit(); + } + } +} + /// Given a specializing impl `impl1`, and the base impl `impl2`, returns two /// substitutions `(S1, S2)` that equate their trait references. The returned /// types are expressed in terms of the generics of `impl1`. @@ -155,7 +176,7 @@ fn get_impl_substs<'tcx>( let errors = ocx.select_all_or_error(); if !errors.is_empty() { - ocx.infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + ocx.infcx.err_ctxt().report_fulfillment_errors(&errors, None); return None; } @@ -193,7 +214,9 @@ fn unconstrained_parent_impl_substs<'tcx>( // the functions in `cgp` add the constrained parameters to a list of // unconstrained parameters. for (predicate, _) in impl_generic_predicates.predicates.iter() { - if let ty::PredicateKind::Projection(proj) = predicate.kind().skip_binder() { + if let ty::PredicateKind::Clause(ty::Clause::Projection(proj)) = + predicate.kind().skip_binder() + { let projection_ty = proj.projection_ty; let projected_ty = proj.term; @@ -278,15 +301,15 @@ fn check_static_lifetimes<'tcx>( /// Check whether predicates on the specializing impl (`impl1`) are allowed. /// -/// Each predicate `P` must be: +/// Each predicate `P` must be one of: /// -/// * global (not reference any parameters) -/// * `T: Tr` predicate where `Tr` is an always-applicable trait -/// * on the base `impl impl2` -/// * Currently this check is done using syntactic equality, which is -/// conservative but generally sufficient. -/// * a well-formed predicate of a type argument of the trait being implemented, +/// * Global (not reference any parameters). +/// * A `T: Tr` predicate where `Tr` is an always-applicable trait. +/// * Present on the base impl `impl2`. +/// * This check is done using the `trait_predicates_eq` function below. +/// * A well-formed predicate of a type argument of the trait being implemented, /// including the `Self`-type. +#[instrument(level = "debug", skip(tcx))] fn check_predicates<'tcx>( tcx: TyCtxt<'tcx>, impl1_def_id: LocalDefId, @@ -322,10 +345,7 @@ fn check_predicates<'tcx>( .map(|obligation| obligation.predicate) .collect() }; - debug!( - "check_always_applicable(\nimpl1_predicates={:?},\nimpl2_predicates={:?}\n)", - impl1_predicates, impl2_predicates, - ); + debug!(?impl1_predicates, ?impl2_predicates); // Since impls of always applicable traits don't get to assume anything, we // can also assume their supertraits apply. @@ -373,25 +393,90 @@ fn check_predicates<'tcx>( ); for (predicate, span) in impl1_predicates { - if !impl2_predicates.contains(&predicate) { + if !impl2_predicates.iter().any(|pred2| trait_predicates_eq(tcx, predicate, *pred2, span)) { check_specialization_on(tcx, predicate, span) } } } +/// Checks if some predicate on the specializing impl (`predicate1`) is the same +/// as some predicate on the base impl (`predicate2`). +/// +/// This basically just checks syntactic equivalence, but is a little more +/// forgiving since we want to equate `T: Tr` with `T: ~const Tr` so this can work: +/// +/// ```ignore (illustrative) +/// #[rustc_specialization_trait] +/// trait Specialize { } +/// +/// impl<T: Bound> Tr for T { } +/// impl<T: ~const Bound + Specialize> const Tr for T { } +/// ``` +/// +/// However, we *don't* want to allow the reverse, i.e., when the bound on the +/// specializing impl is not as const as the bound on the base impl: +/// +/// ```ignore (illustrative) +/// impl<T: ~const Bound> const Tr for T { } +/// impl<T: Bound + Specialize> const Tr for T { } // should be T: ~const Bound +/// ``` +/// +/// So we make that check in this function and try to raise a helpful error message. +fn trait_predicates_eq<'tcx>( + tcx: TyCtxt<'tcx>, + predicate1: ty::Predicate<'tcx>, + predicate2: ty::Predicate<'tcx>, + span: Span, +) -> bool { + let pred1_kind = predicate1.kind().skip_binder(); + let pred2_kind = predicate2.kind().skip_binder(); + let (trait_pred1, trait_pred2) = match (pred1_kind, pred2_kind) { + ( + ty::PredicateKind::Clause(ty::Clause::Trait(pred1)), + ty::PredicateKind::Clause(ty::Clause::Trait(pred2)), + ) => (pred1, pred2), + // Just use plain syntactic equivalence if either of the predicates aren't + // trait predicates or have bound vars. + _ => return predicate1 == predicate2, + }; + + let predicates_equal_modulo_constness = { + let pred1_unconsted = + ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..trait_pred1 }; + let pred2_unconsted = + ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..trait_pred2 }; + pred1_unconsted == pred2_unconsted + }; + + if !predicates_equal_modulo_constness { + return false; + } + + // Check that the predicate on the specializing impl is at least as const as + // the one on the base. + match (trait_pred2.constness, trait_pred1.constness) { + (ty::BoundConstness::ConstIfConst, ty::BoundConstness::NotConst) => { + tcx.sess.struct_span_err(span, "missing `~const` qualifier for specialization").emit(); + } + _ => {} + } + + true +} + +#[instrument(level = "debug", skip(tcx))] fn check_specialization_on<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tcx>, span: Span) { - debug!("can_specialize_on(predicate = {:?})", predicate); match predicate.kind().skip_binder() { // Global predicates are either always true or always false, so we // are fine to specialize on. _ if predicate.is_global() => (), // We allow specializing on explicitly marked traits with no associated // items. - ty::PredicateKind::Trait(ty::TraitPredicate { + ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate { trait_ref, - constness: ty::BoundConstness::NotConst, + constness: _, polarity: _, - }) => { + })) => { if !matches!( trait_predicate_kind(tcx, predicate), Some(TraitSpecializationKind::Marker) @@ -407,7 +492,10 @@ fn check_specialization_on<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tc .emit(); } } - ty::PredicateKind::Projection(ty::ProjectionPredicate { projection_ty, term }) => { + ty::PredicateKind::Clause(ty::Clause::Projection(ty::ProjectionPredicate { + projection_ty, + term, + })) => { tcx.sess .struct_span_err( span, @@ -428,12 +516,14 @@ fn trait_predicate_kind<'tcx>( predicate: ty::Predicate<'tcx>, ) -> Option<TraitSpecializationKind> { match predicate.kind().skip_binder() { - ty::PredicateKind::Trait(ty::TraitPredicate { trait_ref, constness: _, polarity: _ }) => { - Some(tcx.trait_def(trait_ref.def_id).specialization_kind) - } - ty::PredicateKind::RegionOutlives(_) - | ty::PredicateKind::TypeOutlives(_) - | ty::PredicateKind::Projection(_) + ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate { + trait_ref, + constness: _, + polarity: _, + })) => Some(tcx.trait_def(trait_ref.def_id).specialization_kind), + ty::PredicateKind::Clause(ty::Clause::RegionOutlives(_)) + | ty::PredicateKind::Clause(ty::Clause::TypeOutlives(_)) + | ty::PredicateKind::Clause(ty::Clause::Projection(_)) | ty::PredicateKind::WellFormed(_) | ty::PredicateKind::Subtype(_) | ty::PredicateKind::Coerce(_) @@ -441,6 +531,7 @@ fn trait_predicate_kind<'tcx>( | ty::PredicateKind::ClosureKind(..) | ty::PredicateKind::ConstEvaluatable(..) | ty::PredicateKind::ConstEquate(..) + | ty::PredicateKind::Ambiguous | ty::PredicateKind::TypeWellFormedFromEnv(..) => None, } } diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index 525cd2419..2058832d5 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -106,7 +106,7 @@ use rustc_middle::middle; use rustc_middle::ty::query::Providers; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::util; -use rustc_session::config::EntryFnType; +use rustc_session::{config::EntryFnType, parse::feature_err}; use rustc_span::{symbol::sym, Span, DUMMY_SP}; use rustc_target::spec::abi::Abi; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _; @@ -118,20 +118,40 @@ use astconv::AstConv; use bounds::Bounds; fn require_c_abi_if_c_variadic(tcx: TyCtxt<'_>, decl: &hir::FnDecl<'_>, abi: Abi, span: Span) { - match (decl.c_variadic, abi) { - // The function has the correct calling convention, or isn't a "C-variadic" function. - (false, _) | (true, Abi::C { .. }) | (true, Abi::Cdecl { .. }) => {} - // The function is a "C-variadic" function with an incorrect calling convention. - (true, _) => { - let mut err = struct_span_err!( - tcx.sess, + const ERROR_HEAD: &str = "C-variadic function must have a compatible calling convention"; + const CONVENTIONS_UNSTABLE: &str = "`C`, `cdecl`, `win64`, `sysv64` or `efiapi`"; + const CONVENTIONS_STABLE: &str = "`C` or `cdecl`"; + const UNSTABLE_EXPLAIN: &str = + "using calling conventions other than `C` or `cdecl` for varargs functions is unstable"; + + if !decl.c_variadic || matches!(abi, Abi::C { .. } | Abi::Cdecl { .. }) { + return; + } + + let extended_abi_support = tcx.features().extended_varargs_abi_support; + let conventions = match (extended_abi_support, abi.supports_varargs()) { + // User enabled additional ABI support for varargs and function ABI matches those ones. + (true, true) => return, + + // Using this ABI would be ok, if the feature for additional ABI support was enabled. + // Return CONVENTIONS_STABLE, because we want the other error to look the same. + (false, true) => { + feature_err( + &tcx.sess.parse_sess, + sym::extended_varargs_abi_support, span, - E0045, - "C-variadic function must have C or cdecl calling convention" - ); - err.span_label(span, "C-variadics require C or cdecl calling convention").emit(); + UNSTABLE_EXPLAIN, + ) + .emit(); + CONVENTIONS_STABLE } - } + + (false, false) => CONVENTIONS_STABLE, + (true, false) => CONVENTIONS_UNSTABLE, + }; + + let mut err = struct_span_err!(tcx.sess, span, E0045, "{}, like {}", ERROR_HEAD, conventions); + err.span_label(span, ERROR_HEAD).emit(); } fn require_same_types<'tcx>( @@ -153,7 +173,7 @@ fn require_same_types<'tcx>( match &errors[..] { [] => true, errors => { - infcx.err_ctxt().report_fulfillment_errors(errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(errors, None); false } } @@ -312,11 +332,11 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { ObligationCauseCode::MainFunctionType, ); let ocx = traits::ObligationCtxt::new(&infcx); - let norm_return_ty = ocx.normalize(cause.clone(), param_env, return_ty); + let norm_return_ty = ocx.normalize(&cause, param_env, return_ty); ocx.register_bound(cause, param_env, norm_return_ty, term_did); let errors = ocx.select_all_or_error(); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); error = true; } // now we can take the return type of the given main function diff --git a/compiler/rustc_hir_analysis/src/outlives/explicit.rs b/compiler/rustc_hir_analysis/src/outlives/explicit.rs index 7534482cc..663f1c49d 100644 --- a/compiler/rustc_hir_analysis/src/outlives/explicit.rs +++ b/compiler/rustc_hir_analysis/src/outlives/explicit.rs @@ -30,28 +30,30 @@ impl<'tcx> ExplicitPredicatesMap<'tcx> { // process predicates and convert to `RequiredPredicates` entry, see below for &(predicate, span) in predicates.predicates { match predicate.kind().skip_binder() { - ty::PredicateKind::TypeOutlives(OutlivesPredicate(ty, reg)) => { - insert_outlives_predicate( - tcx, - ty.into(), - reg, - span, - &mut required_predicates, - ) - } + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(OutlivesPredicate( + ty, + reg, + ))) => insert_outlives_predicate( + tcx, + ty.into(), + reg, + span, + &mut required_predicates, + ), - ty::PredicateKind::RegionOutlives(OutlivesPredicate(reg1, reg2)) => { - insert_outlives_predicate( - tcx, - reg1.into(), - reg2, - span, - &mut required_predicates, - ) - } + ty::PredicateKind::Clause(ty::Clause::RegionOutlives(OutlivesPredicate( + reg1, + reg2, + ))) => insert_outlives_predicate( + tcx, + reg1.into(), + reg2, + span, + &mut required_predicates, + ), - ty::PredicateKind::Trait(..) - | ty::PredicateKind::Projection(..) + ty::PredicateKind::Clause(ty::Clause::Trait(..)) + | ty::PredicateKind::Clause(ty::Clause::Projection(..)) | ty::PredicateKind::WellFormed(..) | ty::PredicateKind::ObjectSafe(..) | ty::PredicateKind::ClosureKind(..) @@ -59,6 +61,7 @@ impl<'tcx> ExplicitPredicatesMap<'tcx> { | ty::PredicateKind::Coerce(..) | ty::PredicateKind::ConstEvaluatable(..) | ty::PredicateKind::ConstEquate(..) + | ty::PredicateKind::Ambiguous | ty::PredicateKind::TypeWellFormedFromEnv(..) => (), } } diff --git a/compiler/rustc_hir_analysis/src/outlives/mod.rs b/compiler/rustc_hir_analysis/src/outlives/mod.rs index e50c26765..81fe32000 100644 --- a/compiler/rustc_hir_analysis/src/outlives/mod.rs +++ b/compiler/rustc_hir_analysis/src/outlives/mod.rs @@ -3,7 +3,7 @@ use rustc_hir as hir; use rustc_hir::def_id::DefId; use rustc_middle::ty::query::Providers; use rustc_middle::ty::subst::GenericArgKind; -use rustc_middle::ty::{self, CratePredicatesMap, ToPredicate, TyCtxt}; +use rustc_middle::ty::{self, CratePredicatesMap, TyCtxt}; use rustc_span::symbol::sym; use rustc_span::Span; @@ -17,12 +17,12 @@ pub fn provide(providers: &mut Providers) { *providers = Providers { inferred_outlives_of, inferred_outlives_crate, ..*providers }; } -fn inferred_outlives_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[(ty::Predicate<'_>, Span)] { +fn inferred_outlives_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[(ty::Clause<'_>, Span)] { let id = tcx.hir().local_def_id_to_hir_id(item_def_id.expect_local()); if matches!(tcx.def_kind(item_def_id), hir::def::DefKind::AnonConst) && tcx.lazy_normalization() { - if tcx.hir().opt_const_param_default_param_hir_id(id).is_some() { + if tcx.hir().opt_const_param_default_param_def_id(id).is_some() { // In `generics_of` we set the generics' parent to be our parent's parent which means that // we lose out on the predicates of our actual parent if we dont return those predicates here. // (See comment in `generics_of` for more information on why the parent shenanigans is necessary) @@ -50,10 +50,10 @@ fn inferred_outlives_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[(ty::Predicate if tcx.has_attr(item_def_id, sym::rustc_outlives) { let mut pred: Vec<String> = predicates .iter() - .map(|(out_pred, _)| match out_pred.kind().skip_binder() { - ty::PredicateKind::RegionOutlives(p) => p.to_string(), - ty::PredicateKind::TypeOutlives(p) => p.to_string(), - err => bug!("unexpected predicate {:?}", err), + .map(|(out_pred, _)| match out_pred { + ty::Clause::RegionOutlives(p) => p.to_string(), + ty::Clause::TypeOutlives(p) => p.to_string(), + err => bug!("unexpected clause {:?}", err), }) .collect(); pred.sort(); @@ -101,17 +101,11 @@ fn inferred_outlives_crate(tcx: TyCtxt<'_>, (): ()) -> CratePredicatesMap<'_> { |(ty::OutlivesPredicate(kind1, region2), &span)| { match kind1.unpack() { GenericArgKind::Type(ty1) => Some(( - ty::Binder::dummy(ty::PredicateKind::TypeOutlives( - ty::OutlivesPredicate(ty1, *region2), - )) - .to_predicate(tcx), + ty::Clause::TypeOutlives(ty::OutlivesPredicate(ty1, *region2)), span, )), GenericArgKind::Lifetime(region1) => Some(( - ty::Binder::dummy(ty::PredicateKind::RegionOutlives( - ty::OutlivesPredicate(region1, *region2), - )) - .to_predicate(tcx), + ty::Clause::RegionOutlives(ty::OutlivesPredicate(region1, *region2)), span, )), GenericArgKind::Const(_) => { diff --git a/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs b/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs index 435912464..4451db19f 100644 --- a/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs +++ b/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs @@ -296,25 +296,35 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { ) -> String { debug!(?path_hir_id); + // If there was already a lifetime among the arguments, just replicate that one. + if let Some(lt) = self.gen_args.args.iter().find_map(|arg| match arg { + hir::GenericArg::Lifetime(lt) => Some(lt), + _ => None, + }) { + return std::iter::repeat(lt.to_string()) + .take(num_params_to_take) + .collect::<Vec<_>>() + .join(", "); + } + let mut ret = Vec::new(); + let mut ty_id = None; for (id, node) in self.tcx.hir().parent_iter(path_hir_id) { debug!(?id); - let params = if let Some(generics) = node.generics() { - generics.params - } else if let hir::Node::Ty(ty) = node - && let hir::TyKind::BareFn(bare_fn) = ty.kind - { - bare_fn.generic_params - } else { - &[] - }; - ret.extend(params.iter().filter_map(|p| { - let hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Explicit } - = p.kind - else { return None }; - let hir::ParamName::Plain(name) = p.name else { return None }; - Some(name.to_string()) - })); + if let hir::Node::Ty(_) = node { + ty_id = Some(id); + } + + // Suggest `'_` when in function parameter or elided function return. + if let Some(fn_decl) = node.fn_decl() && let Some(ty_id) = ty_id { + let in_arg = fn_decl.inputs.iter().any(|t| t.hir_id == ty_id); + let in_ret = matches!(fn_decl.output, hir::FnRetTy::Return(ty) if ty.hir_id == ty_id); + + if in_arg || (in_ret && fn_decl.lifetime_elision_allowed) { + return std::iter::repeat("'_".to_owned()).take(num_params_to_take).collect::<Vec<_>>().join(", "); + } + } + // Suggest `'static` when in const/static item-like. if let hir::Node::Item(hir::Item { kind: hir::ItemKind::Static { .. } | hir::ItemKind::Const { .. }, @@ -334,11 +344,29 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { }) | hir::Node::AnonConst(..) = node { - ret.extend( - std::iter::repeat("'static".to_owned()) - .take(num_params_to_take.saturating_sub(ret.len())), - ); + return std::iter::repeat("'static".to_owned()) + .take(num_params_to_take.saturating_sub(ret.len())) + .collect::<Vec<_>>() + .join(", "); } + + let params = if let Some(generics) = node.generics() { + generics.params + } else if let hir::Node::Ty(ty) = node + && let hir::TyKind::BareFn(bare_fn) = ty.kind + { + bare_fn.generic_params + } else { + &[] + }; + ret.extend(params.iter().filter_map(|p| { + let hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Explicit } + = p.kind + else { return None }; + let hir::ParamName::Plain(name) = p.name else { return None }; + Some(name.to_string()) + })); + if ret.len() >= num_params_to_take { return ret[..num_params_to_take].join(", "); } @@ -728,7 +756,8 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { && let Some(trait_path_segment) = path.segments.get(0) { let num_generic_args_supplied_to_trait = trait_path_segment.args().num_generic_params(); - if num_assoc_fn_excess_args == num_trait_generics_except_self - num_generic_args_supplied_to_trait { + if num_generic_args_supplied_to_trait + num_assoc_fn_excess_args == num_trait_generics_except_self + { if let Some(span) = self.gen_args.span_ext() && let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) { let sugg = vec![ diff --git a/compiler/rustc_hir_analysis/src/variance/constraints.rs b/compiler/rustc_hir_analysis/src/variance/constraints.rs index eaf0310d5..6ce0c18bf 100644 --- a/compiler/rustc_hir_analysis/src/variance/constraints.rs +++ b/compiler/rustc_hir_analysis/src/variance/constraints.rs @@ -72,8 +72,8 @@ pub fn add_constraints_from_crate<'a, 'tcx>( let adt = tcx.adt_def(def_id); for variant in adt.variants() { - if let Some(ctor) = variant.ctor_def_id { - constraint_cx.build_constraints_for_item(ctor.expect_local()); + if let Some(ctor_def_id) = variant.ctor_def_id() { + constraint_cx.build_constraints_for_item(ctor_def_id.expect_local()); } } } diff --git a/compiler/rustc_hir_analysis/src/variance/mod.rs b/compiler/rustc_hir_analysis/src/variance/mod.rs index 82103c5a0..8b2719c2f 100644 --- a/compiler/rustc_hir_analysis/src/variance/mod.rs +++ b/compiler/rustc_hir_analysis/src/variance/mod.rs @@ -5,9 +5,11 @@ use rustc_arena::DroplessArena; use rustc_hir::def::DefKind; -use rustc_hir::def_id::DefId; +use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::ty::query::Providers; -use rustc_middle::ty::{self, CrateVariancesMap, TyCtxt}; +use rustc_middle::ty::{self, CrateVariancesMap, SubstsRef, Ty, TyCtxt}; +use rustc_middle::ty::{DefIdTree, TypeSuperVisitable, TypeVisitable}; +use std::ops::ControlFlow; /// Defines the `TermsContext` basically houses an arena where we can /// allocate terms. @@ -50,6 +52,9 @@ fn variances_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[ty::Variance] { | DefKind::Union | DefKind::Variant | DefKind::Ctor(..) => {} + DefKind::OpaqueTy | DefKind::ImplTraitPlaceholder => { + return variance_of_opaque(tcx, item_def_id.expect_local()); + } _ => { // Variance not relevant. span_bug!(tcx.def_span(item_def_id), "asked to compute variance for wrong kind of item") @@ -61,3 +66,125 @@ fn variances_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[ty::Variance] { let crate_map = tcx.crate_variances(()); crate_map.variances.get(&item_def_id).copied().unwrap_or(&[]) } + +#[instrument(level = "trace", skip(tcx), ret)] +fn variance_of_opaque(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Variance] { + let generics = tcx.generics_of(item_def_id); + + // Opaque types may only use regions that are bound. So for + // ```rust + // type Foo<'a, 'b, 'c> = impl Trait<'a> + 'b; + // ``` + // we may not use `'c` in the hidden type. + struct OpaqueTypeLifetimeCollector<'tcx> { + tcx: TyCtxt<'tcx>, + root_def_id: DefId, + variances: Vec<ty::Variance>, + } + + impl<'tcx> OpaqueTypeLifetimeCollector<'tcx> { + #[instrument(level = "trace", skip(self), ret)] + fn visit_opaque(&mut self, def_id: DefId, substs: SubstsRef<'tcx>) -> ControlFlow<!> { + if def_id != self.root_def_id && self.tcx.is_descendant_of(def_id, self.root_def_id) { + let child_variances = self.tcx.variances_of(def_id); + for (a, v) in substs.iter().zip(child_variances) { + if *v != ty::Bivariant { + a.visit_with(self)?; + } + } + ControlFlow::CONTINUE + } else { + substs.visit_with(self) + } + } + } + + impl<'tcx> ty::TypeVisitor<'tcx> for OpaqueTypeLifetimeCollector<'tcx> { + #[instrument(level = "trace", skip(self), ret)] + fn visit_region(&mut self, r: ty::Region<'tcx>) -> ControlFlow<Self::BreakTy> { + if let ty::RegionKind::ReEarlyBound(ebr) = r.kind() { + self.variances[ebr.index as usize] = ty::Invariant; + } + r.super_visit_with(self) + } + + #[instrument(level = "trace", skip(self), ret)] + fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> { + match t.kind() { + ty::Opaque(def_id, substs) => self.visit_opaque(*def_id, substs), + ty::Projection(proj) + if self.tcx.def_kind(proj.item_def_id) == DefKind::ImplTraitPlaceholder => + { + self.visit_opaque(proj.item_def_id, proj.substs) + } + _ => t.super_visit_with(self), + } + } + } + + // By default, RPIT are invariant wrt type and const generics, but they are bivariant wrt + // lifetime generics. + let mut variances: Vec<_> = std::iter::repeat(ty::Invariant).take(generics.count()).collect(); + + // Mark all lifetimes from parent generics as unused (Bivariant). + // This will be overridden later if required. + { + let mut generics = generics; + while let Some(def_id) = generics.parent { + generics = tcx.generics_of(def_id); + for param in &generics.params { + match param.kind { + ty::GenericParamDefKind::Lifetime => { + variances[param.index as usize] = ty::Bivariant; + } + ty::GenericParamDefKind::Type { .. } + | ty::GenericParamDefKind::Const { .. } => {} + } + } + } + } + + let mut collector = + OpaqueTypeLifetimeCollector { tcx, root_def_id: item_def_id.to_def_id(), variances }; + let id_substs = ty::InternalSubsts::identity_for_item(tcx, item_def_id.to_def_id()); + for pred in tcx.bound_explicit_item_bounds(item_def_id.to_def_id()).transpose_iter() { + let pred = pred.map_bound(|(pred, _)| *pred).subst(tcx, id_substs); + debug!(?pred); + + // We only ignore opaque type substs if the opaque type is the outermost type. + // The opaque type may be nested within itself via recursion in e.g. + // type Foo<'a> = impl PartialEq<Foo<'a>>; + // which thus mentions `'a` and should thus accept hidden types that borrow 'a + // instead of requiring an additional `+ 'a`. + match pred.kind().skip_binder() { + ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate { + trait_ref: ty::TraitRef { def_id: _, substs }, + constness: _, + polarity: _, + })) => { + for subst in &substs[1..] { + subst.visit_with(&mut collector); + } + } + ty::PredicateKind::Clause(ty::Clause::Projection(ty::ProjectionPredicate { + projection_ty: ty::ProjectionTy { substs, item_def_id: _ }, + term, + })) => { + for subst in &substs[1..] { + subst.visit_with(&mut collector); + } + term.visit_with(&mut collector); + } + ty::PredicateKind::Clause(ty::Clause::TypeOutlives(ty::OutlivesPredicate( + _, + region, + ))) => { + region.visit_with(&mut collector); + } + _ => { + pred.visit_with(&mut collector); + } + } + } + tcx.arena.alloc_from_iter(collector.variances.into_iter()) +} diff --git a/compiler/rustc_hir_analysis/src/variance/terms.rs b/compiler/rustc_hir_analysis/src/variance/terms.rs index 1f763011e..3b286bb9c 100644 --- a/compiler/rustc_hir_analysis/src/variance/terms.rs +++ b/compiler/rustc_hir_analysis/src/variance/terms.rs @@ -42,22 +42,22 @@ impl<'a> fmt::Debug for VarianceTerm<'a> { } } -// The first pass over the crate simply builds up the set of inferreds. +/// The first pass over the crate simply builds up the set of inferreds. pub struct TermsContext<'a, 'tcx> { pub tcx: TyCtxt<'tcx>, pub arena: &'a DroplessArena, - // For marker types, UnsafeCell, and other lang items where - // variance is hardcoded, records the item-id and the hardcoded - // variance. + /// For marker types, `UnsafeCell`, and other lang items where + /// variance is hardcoded, records the item-id and the hardcoded + /// variance. pub lang_items: Vec<(LocalDefId, Vec<ty::Variance>)>, - // Maps from the node id of an item to the first inferred index - // used for its type & region parameters. + /// Maps from the node id of an item to the first inferred index + /// used for its type & region parameters. pub inferred_starts: LocalDefIdMap<InferredIndex>, - // Maps from an InferredIndex to the term for that variable. + /// Maps from an InferredIndex to the term for that variable. pub inferred_terms: Vec<VarianceTermPtr<'a>>, } @@ -91,8 +91,8 @@ pub fn determine_parameters_to_be_inferred<'a, 'tcx>( let adt = tcx.adt_def(def_id); for variant in adt.variants() { - if let Some(ctor) = variant.ctor_def_id { - terms_cx.add_inferreds_for_item(ctor.expect_local()); + if let Some(ctor_def_id) = variant.ctor_def_id() { + terms_cx.add_inferreds_for_item(ctor_def_id.expect_local()); } } } |