diff options
Diffstat (limited to 'compiler/rustc_ty_utils')
| -rw-r--r-- | compiler/rustc_ty_utils/Cargo.toml | 1 | ||||
| -rw-r--r-- | compiler/rustc_ty_utils/src/layout.rs | 28 | ||||
| -rw-r--r-- | compiler/rustc_ty_utils/src/opaque_types.rs | 132 | 
3 files changed, 91 insertions, 70 deletions
| diff --git a/compiler/rustc_ty_utils/Cargo.toml b/compiler/rustc_ty_utils/Cargo.toml index 4c7a57f2931..7e96b64408c 100644 --- a/compiler/rustc_ty_utils/Cargo.toml +++ b/compiler/rustc_ty_utils/Cargo.toml @@ -7,6 +7,7 @@ edition = "2024" # tidy-alphabetical-start itertools = "0.12" rustc_abi = { path = "../rustc_abi" } +rustc_attr_parsing = { path = "../rustc_attr_parsing" } rustc_data_structures = { path = "../rustc_data_structures" } rustc_errors = { path = "../rustc_errors" } rustc_fluent_macro = { path = "../rustc_fluent_macro" } diff --git a/compiler/rustc_ty_utils/src/layout.rs b/compiler/rustc_ty_utils/src/layout.rs index 5a4bb2c95da..7334beb52c9 100644 --- a/compiler/rustc_ty_utils/src/layout.rs +++ b/compiler/rustc_ty_utils/src/layout.rs @@ -220,6 +220,34 @@ fn layout_of_uncached<'tcx>( .try_to_bits(tcx, cx.typing_env) .ok_or_else(|| error(cx, LayoutError::Unknown(ty)))?; + // FIXME(pattern_types): create implied bounds from pattern types in signatures + // that require that the range end is >= the range start so that we can't hit + // this error anymore without first having hit a trait solver error. + // Very fuzzy on the details here, but pattern types are an internal impl detail, + // so we can just go with this for now + if scalar.is_signed() { + let range = scalar.valid_range_mut(); + let start = layout.size.sign_extend(range.start); + let end = layout.size.sign_extend(range.end); + if end < start { + let guar = tcx.dcx().err(format!( + "pattern type ranges cannot wrap: {start}..={end}" + )); + + return Err(error(cx, LayoutError::ReferencesError(guar))); + } + } else { + let range = scalar.valid_range_mut(); + if range.end < range.start { + let guar = tcx.dcx().err(format!( + "pattern type ranges cannot wrap: {}..={}", + range.start, range.end + )); + + return Err(error(cx, LayoutError::ReferencesError(guar))); + } + }; + let niche = Niche { offset: Size::ZERO, value: scalar.primitive(), diff --git a/compiler/rustc_ty_utils/src/opaque_types.rs b/compiler/rustc_ty_utils/src/opaque_types.rs index 98881905bcf..a107925fb18 100644 --- a/compiler/rustc_ty_utils/src/opaque_types.rs +++ b/compiler/rustc_ty_utils/src/opaque_types.rs @@ -1,8 +1,8 @@ use rustc_data_structures::fx::FxHashSet; use rustc_hir::def::DefKind; use rustc_hir::def_id::LocalDefId; +use rustc_hir::intravisit; use rustc_hir::intravisit::Visitor; -use rustc_hir::{CRATE_HIR_ID, intravisit}; use rustc_middle::bug; use rustc_middle::query::Providers; use rustc_middle::ty::util::{CheckRegions, NotUniqueParam}; @@ -30,14 +30,21 @@ enum CollectionMode { /// For impl trait in assoc types we only permit collecting them from /// associated types of the same impl block. ImplTraitInAssocTypes, - TypeAliasImplTraitTransition, + /// When collecting for an explicit `#[define_opaque]` attribute, find all TAITs + Taits, + /// The default case, only collect RPITs and AsyncFn return types, as these are + /// always defined by the current item. + RpitAndAsyncFnOnly, } impl<'tcx> OpaqueTypeCollector<'tcx> { fn new(tcx: TyCtxt<'tcx>, item: LocalDefId) -> Self { - let mode = match tcx.def_kind(tcx.local_parent(item)) { - DefKind::Impl { of_trait: true } => CollectionMode::ImplTraitInAssocTypes, - _ => CollectionMode::TypeAliasImplTraitTransition, + let mode = match tcx.def_kind(item) { + DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy => { + CollectionMode::ImplTraitInAssocTypes + } + DefKind::TyAlias => CollectionMode::Taits, + _ => CollectionMode::RpitAndAsyncFnOnly, }; Self { tcx, opaques: Vec::new(), item, seen: Default::default(), span: None, mode } } @@ -73,40 +80,6 @@ impl<'tcx> OpaqueTypeCollector<'tcx> { } } - /// Returns `true` if `opaque_hir_id` is a sibling or a child of a sibling of `self.item`. - /// - /// Example: - /// ```ignore UNSOLVED (is this a bug?) - /// # #![feature(type_alias_impl_trait)] - /// pub mod foo { - /// pub mod bar { - /// pub trait Bar { /* ... */ } - /// pub type Baz = impl Bar; - /// - /// # impl Bar for () {} - /// fn f1() -> Baz { /* ... */ } - /// } - /// fn f2() -> bar::Baz { /* ... */ } - /// } - /// ``` - /// - /// and `opaque_def_id` is the `DefId` of the definition of the opaque type `Baz`. - /// For the above example, this function returns `true` for `f1` and `false` for `f2`. - #[instrument(level = "trace", skip(self), ret)] - fn check_tait_defining_scope(&self, opaque_def_id: LocalDefId) -> bool { - let mut hir_id = self.tcx.local_def_id_to_hir_id(self.item); - let opaque_hir_id = self.tcx.local_def_id_to_hir_id(opaque_def_id); - - // Named opaque types can be defined by any siblings or children of siblings. - let scope = self.tcx.hir_get_defining_scope(opaque_hir_id); - // We walk up the node tree until we hit the root or the scope of the opaque type. - while hir_id != scope && hir_id != CRATE_HIR_ID { - hir_id = self.tcx.hir_get_parent_item(hir_id).into(); - } - // Syntactically, we are allowed to define the concrete type if: - hir_id == scope - } - #[instrument(level = "trace", skip(self))] fn collect_taits_declared_in_body(&mut self) { let body = self.tcx.hir_body_owned_by(self.item).value; @@ -139,18 +112,31 @@ impl<'tcx> OpaqueTypeCollector<'tcx> { } // TAITs outside their defining scopes are ignored. - let origin = self.tcx.local_opaque_ty_origin(alias_ty.def_id.expect_local()); - trace!(?origin); - match origin { + match self.tcx.local_opaque_ty_origin(alias_ty.def_id.expect_local()) { rustc_hir::OpaqueTyOrigin::FnReturn { .. } | rustc_hir::OpaqueTyOrigin::AsyncFn { .. } => {} - rustc_hir::OpaqueTyOrigin::TyAlias { in_assoc_ty, .. } => { - if !in_assoc_ty && !self.check_tait_defining_scope(alias_ty.def_id.expect_local()) { - return; + rustc_hir::OpaqueTyOrigin::TyAlias { in_assoc_ty, .. } => match self.mode { + // If we are collecting opaques in an assoc method, we are only looking at assoc types + // mentioned in the assoc method and only at opaques defined in there. We do not + // want to collect TAITs + CollectionMode::ImplTraitInAssocTypes => { + if !in_assoc_ty { + return; + } } - } + // If we are collecting opaques referenced from a `define_opaque` attribute, we + // do not want to look at opaques defined in associated types. Those can only be + // defined by methods on the same impl. + CollectionMode::Taits => { + if in_assoc_ty { + return; + } + } + CollectionMode::RpitAndAsyncFnOnly => return, + }, } + trace!(?alias_ty, "adding"); self.opaques.push(alias_ty.def_id.expect_local()); let parent_count = self.tcx.generics_of(alias_ty.def_id).parent_count; @@ -192,6 +178,32 @@ impl<'tcx> OpaqueTypeCollector<'tcx> { } } } + + /// Checks the `#[define_opaque]` attributes on items and collectes opaques to define + /// from the referenced types. + #[instrument(level = "trace", skip(self))] + fn collect_taits_from_defines_attr(&mut self) { + let hir_id = self.tcx.local_def_id_to_hir_id(self.item); + if !hir_id.is_owner() { + return; + } + let Some(defines) = self.tcx.hir_attrs(hir_id.owner).define_opaque else { + return; + }; + for &(span, define) in defines { + trace!(?define); + let mode = std::mem::replace(&mut self.mode, CollectionMode::Taits); + let n = self.opaques.len(); + super::sig_types::walk_types(self.tcx, define, self); + if n == self.opaques.len() { + self.tcx.dcx().span_err(span, "item does not contain any opaque types"); + } + self.mode = mode; + } + // Allow using `#[define_opaque]` on assoc methods and type aliases to override the default collection mode in + // case it was capturing too much. + self.mode = CollectionMode::RpitAndAsyncFnOnly; + } } impl<'tcx> super::sig_types::SpannedTypeVisitor<'tcx> for OpaqueTypeCollector<'tcx> { @@ -210,6 +222,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for OpaqueTypeCollector<'tcx> { self.visit_opaque_ty(alias_ty); } // Skips type aliases, as they are meant to be transparent. + // FIXME(type_alias_impl_trait): can we require mentioning nested type aliases explicitly? ty::Alias(ty::Weak, alias_ty) if alias_ty.def_id.is_local() => { self.tcx .type_of(alias_ty.def_id) @@ -283,28 +296,6 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for OpaqueTypeCollector<'tcx> { self.visit_opaque_ty(alias_ty); } } - ty::Adt(def, _) if def.did().is_local() => { - if let CollectionMode::ImplTraitInAssocTypes = self.mode { - return; - } - if !self.seen.insert(def.did().expect_local()) { - return; - } - for variant in def.variants().iter() { - for field in variant.fields.iter() { - // Don't use the `ty::Adt` args, we either - // * found the opaque in the args - // * will find the opaque in the uninstantiated fields - // The only other situation that can occur is that after instantiating, - // some projection resolves to an opaque that we would have otherwise - // not found. While we could instantiate and walk those, that would mean we - // would have to walk all generic parameters of an Adt, which can quickly - // degenerate into looking at an exponential number of types. - let ty = self.tcx.type_of(field.did).instantiate_identity(); - self.visit_spanned(self.tcx.def_span(field.did), ty); - } - } - } _ => trace!(kind=?t.kind()), } } @@ -317,7 +308,9 @@ fn opaque_types_defined_by<'tcx>( let kind = tcx.def_kind(item); trace!(?kind); let mut collector = OpaqueTypeCollector::new(tcx, item); + collector.collect_taits_from_defines_attr(); super::sig_types::walk_types(tcx, item, &mut collector); + match kind { DefKind::AssocFn | DefKind::Fn @@ -350,8 +343,7 @@ fn opaque_types_defined_by<'tcx>( | DefKind::GlobalAsm | DefKind::Impl { .. } | DefKind::SyntheticCoroutineBody => {} - // Closures and coroutines are type checked with their parent, so we need to allow all - // opaques from the closure signature *and* from the parent body. + // Closures and coroutines are type checked with their parent DefKind::Closure | DefKind::InlineConst => { collector.opaques.extend(tcx.opaque_types_defined_by(tcx.local_parent(item))); } | 
