diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs index c9f5dd0f2c68b..2fa602520dcb0 100644 --- a/compiler/rustc_codegen_llvm/src/llvm_util.rs +++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs @@ -494,6 +494,11 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec= (14, 0, 0) && sess.target.arch == "aarch64" { + features.push("+v8a".into()); + } + if diagnostics && let Some(f) = check_tied_features(sess, &featsmap) { sess.emit_err(TargetFeatureDisableOrEnable { features: f, diff --git a/compiler/rustc_hir_analysis/src/check/compare_method.rs b/compiler/rustc_hir_analysis/src/check/compare_method.rs index ba58672e7595a..82a77416a190c 100644 --- a/compiler/rustc_hir_analysis/src/check/compare_method.rs +++ b/compiler/rustc_hir_analysis/src/check/compare_method.rs @@ -173,13 +173,11 @@ 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 @@ -338,6 +336,7 @@ pub fn collect_trait_impl_trait_tys<'tcx>( // 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; @@ -722,12 +721,14 @@ 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={:?} \ @@ -761,12 +762,16 @@ fn check_region_bounds_on_impl_item<'tcx>( 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 reported = tcx + .sess + .create_err(LifetimesOrBoundsMismatchOnTrait { + span, + item_kind: assoc_item_kind_str(impl_m), + ident: impl_m.ident(tcx), + generics_span, + }) + .emit_unless(delay); + return Err(reported); } @@ -1504,18 +1509,10 @@ 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); diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index 2bcb47cc38399..5aebccac6a295 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -80,7 +80,6 @@ pub struct InferOk<'tcx, T> { } pub type InferResult<'tcx, T> = Result, TypeError<'tcx>>; -pub type Bound = Option; pub type UnitResult<'tcx> = RelateResult<'tcx, ()>; // "unify result" pub type FixupResult<'tcx, T> = Result>; // "fixup result" diff --git a/compiler/rustc_middle/src/values.rs b/compiler/rustc_middle/src/values.rs index f4562cdfb88dc..70b98e59a8bea 100644 --- a/compiler/rustc_middle/src/values.rs +++ b/compiler/rustc_middle/src/values.rs @@ -32,13 +32,23 @@ impl<'tcx> Value> for ty::SymbolName<'_> { } impl<'tcx> Value> for ty::Binder<'_, ty::FnSig<'_>> { - fn from_cycle_error(tcx: TyCtxt<'tcx>, _: &[QueryInfo]) -> Self { + fn from_cycle_error(tcx: TyCtxt<'tcx>, stack: &[QueryInfo]) -> Self { let err = tcx.ty_error(); - // FIXME(compiler-errors): It would be nice if we could get the - // query key, so we could at least generate a fn signature that - // has the right arity. + + let arity = if let Some(frame) = stack.get(0) + && frame.query.name == "fn_sig" + && let Some(def_id) = frame.query.def_id + && let Some(node) = tcx.hir().get_if_local(def_id) + && let Some(sig) = node.fn_sig() + { + sig.decl.inputs.len() + sig.decl.implicit_self.has_implicit_self() as usize + } else { + tcx.sess.abort_if_errors(); + unreachable!() + }; + let fn_sig = ty::Binder::dummy(tcx.mk_fn_sig( - [].into_iter(), + std::iter::repeat(err).take(arity), err, false, rustc_hir::Unsafety::Normal, diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs index 99724fb28db11..899e30275a052 100644 --- a/compiler/rustc_trait_selection/src/traits/coherence.rs +++ b/compiler/rustc_trait_selection/src/traits/coherence.rs @@ -11,8 +11,8 @@ use crate::traits::select::IntercrateAmbiguityCause; use crate::traits::util::impl_subject_and_oblig; use crate::traits::SkipLeakCheck; use crate::traits::{ - self, Normalized, Obligation, ObligationCause, ObligationCtxt, PredicateObligation, - PredicateObligations, SelectionContext, + self, Obligation, ObligationCause, ObligationCtxt, PredicateObligation, PredicateObligations, + SelectionContext, }; use rustc_data_structures::fx::FxIndexSet; use rustc_errors::Diagnostic; @@ -30,6 +30,8 @@ use std::fmt::Debug; use std::iter; use std::ops::ControlFlow; +use super::NormalizeExt; + /// Whether we do the orphan check relative to this crate or /// to some remote crate. #[derive(Copy, Clone, Debug)] @@ -128,8 +130,8 @@ fn with_fresh_ty_vars<'cx, 'tcx>( predicates: tcx.predicates_of(impl_def_id).instantiate(tcx, impl_substs).predicates, }; - let Normalized { value: mut header, obligations } = - traits::normalize(selcx, param_env, ObligationCause::dummy(), header); + let InferOk { value: mut header, obligations } = + selcx.infcx.at(&ObligationCause::dummy(), param_env).normalize(header); header.predicates.extend(obligations.into_iter().map(|o| o.predicate)); header diff --git a/compiler/rustc_trait_selection/src/traits/engine.rs b/compiler/rustc_trait_selection/src/traits/engine.rs index 64d01ddb09a49..26d4b94e700d3 100644 --- a/compiler/rustc_trait_selection/src/traits/engine.rs +++ b/compiler/rustc_trait_selection/src/traits/engine.rs @@ -112,6 +112,27 @@ impl<'a, 'tcx> ObligationCtxt<'a, 'tcx> { self.register_infer_ok_obligations(infer_ok) } + /// Makes `expected <: actual`. + /// + /// See [`At::trace_exp`] and [`Trace::eq`] for a version of + /// this method that only requires `T: Relate<'tcx>` + pub fn eq_exp( + &self, + cause: &ObligationCause<'tcx>, + param_env: ty::ParamEnv<'tcx>, + a_is_expected: bool, + a: T, + b: T, + ) -> Result<(), TypeError<'tcx>> + where + T: ToTrace<'tcx>, + { + self.infcx + .at(cause, param_env) + .eq_exp(a_is_expected, a, b) + .map(|infer_ok| self.register_infer_ok_obligations(infer_ok)) + } + pub fn eq>( &self, cause: &ObligationCause<'tcx>, diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs index 049b24b39975d..84e951e80230b 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs @@ -1577,32 +1577,26 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> { } self.probe(|_| { - let mut err = error.err; - let mut values = None; + let ocx = ObligationCtxt::new_in_snapshot(self); // try to find the mismatched types to report the error with. // // this can fail if the problem was higher-ranked, in which // cause I have no idea for a good error message. let bound_predicate = predicate.kind(); - if let ty::PredicateKind::Clause(ty::Clause::Projection(data)) = + let (values, err) = if let ty::PredicateKind::Clause(ty::Clause::Projection(data)) = bound_predicate.skip_binder() { - let mut selcx = SelectionContext::new(self); let data = self.replace_bound_vars_with_fresh_vars( obligation.cause.span, infer::LateBoundRegionConversionTime::HigherRankedType, bound_predicate.rebind(data), ); - let mut obligations = vec![]; - // FIXME(normalization): Change this to use `At::normalize` - let normalized_ty = super::normalize_projection_type( - &mut selcx, + let normalized_ty = ocx.normalize( + &obligation.cause, obligation.param_env, - data.projection_ty, - obligation.cause.clone(), - 0, - &mut obligations, + self.tcx + .mk_projection(data.projection_ty.item_def_id, data.projection_ty.substs), ); debug!(?obligation.cause, ?obligation.param_env); @@ -1618,19 +1612,34 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> { | ObligationCauseCode::ObjectCastObligation(..) | ObligationCauseCode::OpaqueType ); - if let Err(new_err) = self.at(&obligation.cause, obligation.param_env).eq_exp( + let expected_ty = data.term.ty().unwrap(); + + // constrain inference variables a bit more to nested obligations from normalize so + // we can have more helpful errors. + ocx.select_where_possible(); + + if let Err(new_err) = ocx.eq_exp( + &obligation.cause, + obligation.param_env, is_normalized_ty_expected, normalized_ty, - data.term, + expected_ty, ) { - values = Some((data, is_normalized_ty_expected, normalized_ty, data.term)); - err = new_err; + (Some((data, is_normalized_ty_expected, normalized_ty, expected_ty)), new_err) + } else { + (None, error.err) } - } + } else { + (None, error.err) + }; let msg = values .and_then(|(predicate, _, normalized_ty, expected_ty)| { - self.maybe_detailed_projection_msg(predicate, normalized_ty, expected_ty) + self.maybe_detailed_projection_msg( + predicate, + normalized_ty.into(), + expected_ty.into(), + ) }) .unwrap_or_else(|| format!("type mismatch resolving `{}`", predicate)); let mut diag = struct_span_err!(self.tcx.sess, obligation.cause.span, E0271, "{msg}"); @@ -1672,11 +1681,11 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> { &mut diag, &obligation.cause, secondary_span, - values.map(|(_, is_normalized_ty_expected, normalized_ty, term)| { + values.map(|(_, is_normalized_ty_expected, normalized_ty, expected_ty)| { infer::ValuePairs::Terms(ExpectedFound::new( is_normalized_ty_expected, - normalized_ty, - term, + normalized_ty.into(), + expected_ty.into(), )) }), err, diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index 371367f0deb3e..c6818a4e57d42 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -56,7 +56,6 @@ pub use self::object_safety::astconv_object_safety_violations; pub use self::object_safety::is_vtable_safe_method; pub use self::object_safety::MethodViolationCode; pub use self::object_safety::ObjectSafetyViolation; -pub(crate) use self::project::{normalize, normalize_to}; pub use self::project::{normalize_projection_type, NormalizeExt}; pub use self::select::{EvaluationCache, SelectionCache, SelectionContext}; pub use self::select::{EvaluationResult, IntercrateAmbiguityCause, OverflowError}; diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs index 113803cd1790a..051660be9c474 100644 --- a/compiler/rustc_trait_selection/src/traits/project.rs +++ b/compiler/rustc_trait_selection/src/traits/project.rs @@ -50,6 +50,10 @@ pub type ProjectionTyObligation<'tcx> = Obligation<'tcx, ty::ProjectionTy<'tcx>> pub(super) struct InProgress; pub trait NormalizeExt<'tcx> { + /// Normalize a value using the `AssocTypeNormalizer`. + /// + /// This normalization should be used when the type contains inference variables or the + /// projection may be fallible. fn normalize>(&self, t: T) -> InferOk<'tcx, T>; } @@ -57,7 +61,7 @@ impl<'tcx> NormalizeExt<'tcx> for At<'_, 'tcx> { fn normalize>(&self, value: T) -> InferOk<'tcx, T> { let mut selcx = SelectionContext::new(self.infcx); let Normalized { value, obligations } = - normalize(&mut selcx, self.param_env, self.cause.clone(), value); + normalize_with_depth(&mut selcx, self.param_env, self.cause.clone(), 0, value); InferOk { value, obligations } } } @@ -303,37 +307,6 @@ fn project_and_unify_type<'cx, 'tcx>( } } -/// Normalizes any associated type projections in `value`, replacing -/// them with a fully resolved type where possible. The return value -/// combines the normalized result and any additional obligations that -/// were incurred as result. -pub(crate) fn normalize<'a, 'b, 'tcx, T>( - selcx: &'a mut SelectionContext<'b, 'tcx>, - param_env: ty::ParamEnv<'tcx>, - cause: ObligationCause<'tcx>, - value: T, -) -> Normalized<'tcx, T> -where - T: TypeFoldable<'tcx>, -{ - let mut obligations = Vec::new(); - let value = normalize_to(selcx, param_env, cause, value, &mut obligations); - Normalized { value, obligations } -} - -pub(crate) fn normalize_to<'a, 'b, 'tcx, T>( - selcx: &'a mut SelectionContext<'b, 'tcx>, - param_env: ty::ParamEnv<'tcx>, - cause: ObligationCause<'tcx>, - value: T, - obligations: &mut Vec>, -) -> T -where - T: TypeFoldable<'tcx>, -{ - normalize_with_depth_to(selcx, param_env, cause, 0, value, obligations) -} - /// As `normalize`, but with a custom depth. pub(crate) fn normalize_with_depth<'a, 'b, 'tcx, T>( selcx: &'a mut SelectionContext<'b, 'tcx>, @@ -2324,10 +2297,11 @@ fn confirm_impl_trait_in_trait_candidate<'tcx>( }, )); - let ty = super::normalize_to( + let ty = normalize_with_depth_to( selcx, obligation.param_env, cause.clone(), + obligation.recursion_depth + 1, tcx.bound_trait_impl_trait_tys(impl_fn_def_id) .map_bound(|tys| { tys.map_or_else(|_| tcx.ty_error(), |tys| tys[&obligation.predicate.item_def_id]) diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs index 1aed66308709e..f899321fc01e1 100644 --- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs +++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs @@ -23,6 +23,13 @@ use super::NoSolution; pub use rustc_middle::traits::query::NormalizationResult; pub trait QueryNormalizeExt<'tcx> { + /// Normalize a value using the `QueryNormalizer`. + /// + /// This normalization should *only* be used when the projection does not + /// have possible ambiguity or may not be well-formed. + /// + /// After codegen, when lifetimes do not matter, it is preferable to instead + /// use [`TyCtxt::normalize_erasing_regions`], which wraps this procedure. fn query_normalize(&self, value: T) -> Result, NoSolution> where T: TypeFoldable<'tcx>; diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css index 6bff2cd2f1aa0..e9f2e025774e5 100644 --- a/src/librustdoc/html/static/css/rustdoc.css +++ b/src/librustdoc/html/static/css/rustdoc.css @@ -908,6 +908,7 @@ so that we can apply CSS-filters to change the arrow color in themes */ .popover { position: absolute; + top: 100%; right: 0; z-index: 2; display: block; @@ -1357,22 +1358,24 @@ a.test-arrow:hover { } #settings-menu, #help-button { margin-left: 4px; - outline: none; + display: flex; } #settings-menu > a, #help-button > a, #copy-path { width: 33px; - line-height: 1.5; } #settings-menu > a, #help-button > a { - padding: 5px; - height: 100%; - display: block; + display: flex; + align-items: center; + justify-content: center; background-color: var(--button-background-color); border: 1px solid var(--border-color); border-radius: 2px; color: var(--settings-button-color); + /* Rare exception to specifying font sizes in rem. Since this is acting + as an icon, it's okay to specify their sizes in pixels. */ + font-size: 20px; } #settings-menu > a:hover, #settings-menu > a:focus, @@ -1408,14 +1411,6 @@ a.test-arrow:hover { animation: rotating 2s linear infinite; } -#help-button > a { - text-align: center; - /* Rare exception to specifying font sizes in rem. Since this is acting - as an icon, it's okay to specify their sizes in pixels. */ - font-size: 20px; - padding-top: 2px; -} - kbd { display: inline-block; padding: 3px 5px; @@ -1658,10 +1653,6 @@ in storage.js content: "Since "; } - #copy-path { - display: none; - } - /* Hide the logo and item name from the sidebar. Those are displayed in the mobile-topbar instead. */ .sidebar .sidebar-logo, @@ -1795,8 +1786,8 @@ in storage.js border-bottom: 1px solid; } - /* We don't display the help button on mobile devices. */ - #help-button { + /* We don't display these buttons on mobile devices. */ + #copy-path, #help-button { display: none; } diff --git a/src/test/assembly/asm/aarch64-el2vmsa.rs b/src/test/assembly/asm/aarch64-el2vmsa.rs new file mode 100644 index 0000000000000..1908ffb8ff3f0 --- /dev/null +++ b/src/test/assembly/asm/aarch64-el2vmsa.rs @@ -0,0 +1,37 @@ +// assembly-output: emit-asm +// compile-flags: --target aarch64-unknown-linux-gnu +// needs-llvm-components: aarch64 + +#![feature(no_core, lang_items, rustc_attrs)] +#![crate_type = "rlib"] +#![no_core] + +#[rustc_builtin_macro] +macro_rules! asm { + () => {}; +} + +#[lang = "sized"] +trait Sized {} + +// CHECK-LABEL: ttbr0_el2: +#[no_mangle] +pub fn ttbr0_el2() { + // CHECK: //APP + // CHECK-NEXT: msr TTBR0_EL2, x0 + // CHECK-NEXT: //NO_APP + unsafe { + asm!("msr ttbr0_el2, x0"); + } +} + +// CHECK-LABEL: vttbr_el2: +#[no_mangle] +pub fn vttbr_el2() { + // CHECK: //APP + // CHECK-NEXT: msr VTTBR_EL2, x0 + // CHECK-NEXT: //NO_APP + unsafe { + asm!("msr vttbr_el2, x0"); + } +} diff --git a/src/test/assembly/sparc-struct-abi.rs b/src/test/assembly/sparc-struct-abi.rs index 6a898b2974a65..6309dd420ffa4 100644 --- a/src/test/assembly/sparc-struct-abi.rs +++ b/src/test/assembly/sparc-struct-abi.rs @@ -44,12 +44,16 @@ pub unsafe extern "C" fn callee(arg: Franta) { tst_use(arg.b); tst_use(arg.c); tst_use(arg.d); + tail_call_avoidance_fn(); } extern "C" { fn opaque_callee(arg: Franta, intarg: i32); fn tst_use(arg: f32); fn clobber(); + // This exists so that post-https://reviews.llvm.org/D138741 LLVM doesn't + // tail-call away some of our assertions. + fn tail_call_avoidance_fn(); } #[no_mangle] @@ -62,4 +66,5 @@ pub unsafe extern "C" fn caller() { // CHECK: call opaque_callee // CHECK: mov 3, %o2 opaque_callee(Franta { a: 1.0, b: 2.0, c: 3.0, d: 4.0 }, 3); + tail_call_avoidance_fn(); } diff --git a/src/test/ui/async-await/in-trait/lifetime-mismatch.rs b/src/test/ui/async-await/in-trait/lifetime-mismatch.rs new file mode 100644 index 0000000000000..45ede193c0fc6 --- /dev/null +++ b/src/test/ui/async-await/in-trait/lifetime-mismatch.rs @@ -0,0 +1,20 @@ +// edition:2021 + +#![feature(async_fn_in_trait)] +//~^ WARN the feature `async_fn_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes + +trait MyTrait { + async fn foo<'a>(&self); + async fn bar(&self); +} + +impl MyTrait for i32 { + async fn foo(&self) {} + //~^ ERROR lifetime parameters or bounds on method `foo` do not match the trait declaration + + async fn bar(&self) { + self.foo(); + } +} + +fn main() {} diff --git a/src/test/ui/async-await/in-trait/lifetime-mismatch.stderr b/src/test/ui/async-await/in-trait/lifetime-mismatch.stderr new file mode 100644 index 0000000000000..d87adcc78b6c8 --- /dev/null +++ b/src/test/ui/async-await/in-trait/lifetime-mismatch.stderr @@ -0,0 +1,21 @@ +warning: the feature `async_fn_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/lifetime-mismatch.rs:3:12 + | +LL | #![feature(async_fn_in_trait)] + | ^^^^^^^^^^^^^^^^^ + | + = note: see issue #91611 for more information + = note: `#[warn(incomplete_features)]` on by default + +error[E0195]: lifetime parameters or bounds on method `foo` do not match the trait declaration + --> $DIR/lifetime-mismatch.rs:12:17 + | +LL | async fn foo<'a>(&self); + | ---- lifetimes in impl do not match this method in trait +... +LL | async fn foo(&self) {} + | ^ lifetimes do not match method in trait + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0195`. diff --git a/src/test/ui/query-system/fn-sig-cycle-arity.rs b/src/test/ui/query-system/fn-sig-cycle-arity.rs new file mode 100644 index 0000000000000..7a9b8469c9e19 --- /dev/null +++ b/src/test/ui/query-system/fn-sig-cycle-arity.rs @@ -0,0 +1,8 @@ +trait Dancer { + fn dance(&self) -> _ { + //~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types + self.dance() + } +} + +fn main() {} diff --git a/src/test/ui/query-system/fn-sig-cycle-arity.stderr b/src/test/ui/query-system/fn-sig-cycle-arity.stderr new file mode 100644 index 0000000000000..67e0c2545515e --- /dev/null +++ b/src/test/ui/query-system/fn-sig-cycle-arity.stderr @@ -0,0 +1,9 @@ +error[E0121]: the placeholder `_` is not allowed within types on item signatures for return types + --> $DIR/fn-sig-cycle-arity.rs:2:24 + | +LL | fn dance(&self) -> _ { + | ^ not allowed in type signatures + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0121`.