diff options
Diffstat (limited to 'compiler/rustc_ast_lowering/src/lib.rs')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/lib.rs | 139 |
1 files changed, 71 insertions, 68 deletions
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index 88f6e6c3b78..f18ceb62e0b 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -51,9 +51,9 @@ use rustc_data_structures::sorted_map::SortedMap; use rustc_data_structures::stable_hasher::{HashStable, StableHasher}; use rustc_data_structures::sync::Lrc; use rustc_errors::{DiagArgFromDisplay, DiagCtxt, StashKey}; -use rustc_hir as hir; use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res}; use rustc_hir::def_id::{LocalDefId, LocalDefIdMap, CRATE_DEF_ID, LOCAL_CRATE}; +use rustc_hir::{self as hir}; use rustc_hir::{ ConstArg, GenericArg, HirId, ItemLocalMap, MissingLifetimeKind, ParamName, TraitCandidate, }; @@ -1384,6 +1384,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } None } + // Ignore `use` syntax since that is not valid in objects. + GenericBound::Use(_, span) => { + this.dcx() + .span_delayed_bug(*span, "use<> not allowed in dyn types"); + None + } })); let lifetime_bound = lifetime_bound.unwrap_or_else(|| this.elided_dyn_bound(t.span)); @@ -1391,7 +1397,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { }); hir::TyKind::TraitObject(bounds, lifetime_bound, *kind) } - TyKind::ImplTrait(def_node_id, bounds, precise_capturing) => { + TyKind::ImplTrait(def_node_id, bounds) => { let span = t.span; match itctx { ImplTraitContext::OpaqueTy { origin, fn_kind } => self.lower_opaque_impl_trait( @@ -1401,12 +1407,15 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { bounds, fn_kind, itctx, - precise_capturing.as_deref().map(|(args, span)| (args.as_slice(), *span)), ), ImplTraitContext::Universal => { - if let Some(&(_, span)) = precise_capturing.as_deref() { + if let Some(span) = bounds.iter().find_map(|bound| match *bound { + ast::GenericBound::Use(_, span) => Some(span), + _ => None, + }) { self.tcx.dcx().emit_err(errors::NoPreciseCapturesOnApit { span }); - }; + } + let span = t.span; // HACK: pprust breaks strings with newlines when the type @@ -1517,7 +1526,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { bounds: &GenericBounds, fn_kind: Option<FnDeclKind>, itctx: ImplTraitContext, - precise_capturing_args: Option<(&[PreciseCapturingArg], Span)>, ) -> hir::TyKind<'hir> { // Make sure we know that some funky desugaring has been going on here. // This is a first: there is code in other places like for loop @@ -1526,59 +1534,64 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // frequently opened issues show. let opaque_ty_span = self.mark_span_with_reason(DesugaringKind::OpaqueTy, span, None); - let captured_lifetimes_to_duplicate = - if let Some((precise_capturing, _)) = precise_capturing_args { - // We'll actually validate these later on; all we need is the list of - // lifetimes to duplicate during this portion of lowering. - precise_capturing - .iter() - .filter_map(|arg| match arg { - PreciseCapturingArg::Lifetime(lt) => Some(*lt), - PreciseCapturingArg::Arg(..) => None, - }) - // Add in all the lifetimes mentioned in the bounds. We will error - // them out later, but capturing them here is important to make sure - // they actually get resolved in resolve_bound_vars. - .chain(lifetime_collector::lifetimes_in_bounds(self.resolver, bounds)) - .collect() - } else { - match origin { - hir::OpaqueTyOrigin::TyAlias { .. } => { - // type alias impl trait and associated type position impl trait were - // decided to capture all in-scope lifetimes, which we collect for - // all opaques during resolution. + let captured_lifetimes_to_duplicate = if let Some(args) = + // We only look for one `use<...>` syntax since we syntactially reject more than one. + bounds.iter().find_map( + |bound| match bound { + ast::GenericBound::Use(a, _) => Some(a), + _ => None, + }, + ) { + // We'll actually validate these later on; all we need is the list of + // lifetimes to duplicate during this portion of lowering. + args.iter() + .filter_map(|arg| match arg { + PreciseCapturingArg::Lifetime(lt) => Some(*lt), + PreciseCapturingArg::Arg(..) => None, + }) + // Add in all the lifetimes mentioned in the bounds. We will error + // them out later, but capturing them here is important to make sure + // they actually get resolved in resolve_bound_vars. + .chain(lifetime_collector::lifetimes_in_bounds(self.resolver, bounds)) + .collect() + } else { + match origin { + hir::OpaqueTyOrigin::TyAlias { .. } => { + // type alias impl trait and associated type position impl trait were + // decided to capture all in-scope lifetimes, which we collect for + // all opaques during resolution. + self.resolver + .take_extra_lifetime_params(opaque_ty_node_id) + .into_iter() + .map(|(ident, id, _)| Lifetime { id, ident }) + .collect() + } + hir::OpaqueTyOrigin::FnReturn(..) => { + if matches!( + fn_kind.expect("expected RPITs to be lowered with a FnKind"), + FnDeclKind::Impl | FnDeclKind::Trait + ) || self.tcx.features().lifetime_capture_rules_2024 + || span.at_least_rust_2024() + { + // return-position impl trait in trait was decided to capture all + // in-scope lifetimes, which we collect for all opaques during resolution. self.resolver .take_extra_lifetime_params(opaque_ty_node_id) .into_iter() .map(|(ident, id, _)| Lifetime { id, ident }) .collect() - } - hir::OpaqueTyOrigin::FnReturn(..) => { - if matches!( - fn_kind.expect("expected RPITs to be lowered with a FnKind"), - FnDeclKind::Impl | FnDeclKind::Trait - ) || self.tcx.features().lifetime_capture_rules_2024 - || span.at_least_rust_2024() - { - // return-position impl trait in trait was decided to capture all - // in-scope lifetimes, which we collect for all opaques during resolution. - self.resolver - .take_extra_lifetime_params(opaque_ty_node_id) - .into_iter() - .map(|(ident, id, _)| Lifetime { id, ident }) - .collect() - } else { - // in fn return position, like the `fn test<'a>() -> impl Debug + 'a` - // example, we only need to duplicate lifetimes that appear in the - // bounds, since those are the only ones that are captured by the opaque. - lifetime_collector::lifetimes_in_bounds(self.resolver, bounds) - } - } - hir::OpaqueTyOrigin::AsyncFn(..) => { - unreachable!("should be using `lower_async_fn_ret_ty`") + } else { + // in fn return position, like the `fn test<'a>() -> impl Debug + 'a` + // example, we only need to duplicate lifetimes that appear in the + // bounds, since those are the only ones that are captured by the opaque. + lifetime_collector::lifetimes_in_bounds(self.resolver, bounds) } } - }; + hir::OpaqueTyOrigin::AsyncFn(..) => { + unreachable!("should be using `lower_async_fn_ret_ty`") + } + } + }; debug!(?captured_lifetimes_to_duplicate); self.lower_opaque_inner( @@ -1588,7 +1601,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { captured_lifetimes_to_duplicate, span, opaque_ty_span, - precise_capturing_args, |this| this.lower_param_bounds(bounds, itctx), ) } @@ -1601,7 +1613,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { captured_lifetimes_to_duplicate: FxIndexSet<Lifetime>, span: Span, opaque_ty_span: Span, - precise_capturing_args: Option<(&[PreciseCapturingArg], Span)>, lower_item_bounds: impl FnOnce(&mut Self) -> &'hir [hir::GenericBound<'hir>], ) -> hir::TyKind<'hir> { let opaque_ty_def_id = self.create_def( @@ -1688,18 +1699,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Install the remapping from old to new (if any). This makes sure that // any lifetimes that would have resolved to the def-id of captured // lifetimes are remapped to the new *synthetic* lifetimes of the opaque. - let (bounds, precise_capturing_args) = - this.with_remapping(captured_to_synthesized_mapping, |this| { - ( - lower_item_bounds(this), - precise_capturing_args.map(|(precise_capturing, span)| { - ( - this.lower_precise_capturing_args(precise_capturing), - this.lower_span(span), - ) - }), - ) - }); + let bounds = this + .with_remapping(captured_to_synthesized_mapping, |this| lower_item_bounds(this)); let generic_params = this.arena.alloc_from_iter(synthesized_lifetime_definitions.iter().map( @@ -1744,7 +1745,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { origin, lifetime_mapping, in_trait, - precise_capturing_args, }; // Generate an `type Foo = impl Trait;` declaration. @@ -1955,7 +1955,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { captured_lifetimes, span, opaque_ty_span, - None, |this| { let bound = this.lower_coroutine_fn_output_type_to_bound( output, @@ -2038,6 +2037,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { GenericBound::Outlives(lifetime) => { hir::GenericBound::Outlives(self.lower_lifetime(lifetime)) } + GenericBound::Use(args, span) => hir::GenericBound::Use( + self.lower_precise_capturing_args(args), + self.lower_span(*span), + ), } } |