diff --git a/src/librustc_typeck/check/compare_method.rs b/src/librustc_typeck/check/compare_method.rs index b39cfcb377595..98c341f4bed41 100644 --- a/src/librustc_typeck/check/compare_method.rs +++ b/src/librustc_typeck/check/compare_method.rs @@ -4,15 +4,17 @@ use rustc_hir::def::{DefKind, Res}; use rustc_hir::intravisit; use rustc_hir::{GenericParamKind, ImplItemKind, TraitItemKind}; use rustc_infer::infer::{self, InferOk, TyCtxtInferExt}; +use rustc_middle::ty; use rustc_middle::ty::error::{ExpectedFound, TypeError}; -use rustc_middle::ty::subst::{InternalSubsts, Subst}; +use rustc_middle::ty::subst::{InternalSubsts, Subst, SubstsRef}; use rustc_middle::ty::util::ExplicitSelf; -use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt}; +use rustc_middle::ty::{GenericParamDefKind, ToPredicate, TyCtxt, WithConstness}; use rustc_span::Span; use rustc_trait_selection::traits::error_reporting::InferCtxtExt; use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode, Reveal}; use super::{potentially_plural_count, FnCtxt, Inherited}; +use std::iter; /// Checks that a method from an impl conforms to the signature of /// the same method as declared in the trait. @@ -1057,13 +1059,15 @@ crate fn compare_ty_impl<'tcx>( let _: Result<(), ErrorReported> = (|| { compare_number_of_generics(tcx, impl_ty, impl_ty_span, trait_ty, trait_item_span)?; - compare_type_predicate_entailment(tcx, impl_ty, impl_ty_span, trait_ty, impl_trait_ref) + compare_type_predicate_entailment(tcx, impl_ty, impl_ty_span, trait_ty, impl_trait_ref)?; + + compare_projection_bounds(tcx, trait_ty, impl_ty, impl_ty_span, impl_trait_ref) })(); } /// The equivalent of [compare_predicate_entailment], but for associated types /// instead of associated functions. -fn compare_type_predicate_entailment( +fn compare_type_predicate_entailment<'tcx>( tcx: TyCtxt<'tcx>, impl_ty: &ty::AssocItem, impl_ty_span: Span, @@ -1165,6 +1169,152 @@ fn compare_type_predicate_entailment( }) } +/// Validate that `ProjectionCandidate`s created for this associated type will +/// be valid. +/// +/// Usually given +/// +/// trait X { type Y: Copy } impl X for T { type Y = S; } +/// +/// We are able to normalize `::U` to `S`, and so when we check the +/// impl is well-formed we have to prove `S: Copy`. +/// +/// For default associated types the normalization is not possible (the value +/// from the impl could be overridden). We also can't normalize generic +/// associated types (yet) because they contain bound parameters. +fn compare_projection_bounds<'tcx>( + tcx: TyCtxt<'tcx>, + trait_ty: &ty::AssocItem, + impl_ty: &ty::AssocItem, + impl_ty_span: Span, + impl_trait_ref: ty::TraitRef<'tcx>, +) -> Result<(), ErrorReported> { + let is_gat = !tcx.generics_of(impl_ty.def_id).params.is_empty(); + if impl_ty.defaultness.is_final() && !is_gat { + // For "final", non-generic associate type implementations, we + // don't need this as described above. + return Ok(()); + } + + let param_env = tcx.param_env(impl_ty.def_id); + + let impl_substs = InternalSubsts::identity_for_item(tcx, impl_ty.container.id()); + let impl_ty_value = tcx.type_of(impl_ty.def_id); + + // Map the predicate from the trait to the corresponding one for the impl. + // For example: + // + // trait X { type Y<'a>: PartialEq } impl X for T { type Y<'a> = &'a S; } + // impl<'x> X<&'x u32> for () { type Y<'c> = &'c u32; } + // + // For the `for<'a> <>::Y<'a>: PartialEq` bound, this + // function would translate and partially normalize + // `[>::Y<'a>, A]` to `[&'a u32, &'x u32]`. + let translate_predicate_substs = move |predicate_substs: SubstsRef<'tcx>| { + let normalized_self = if !is_gat { + // projection_predicates only includes projections where the + // substs of the trait ref are exactly the trait's identity + // substs, so we can simply return the value from the impl. + impl_ty_value + } else { + let predicate_self_ty = predicate_substs.type_at(0); + let impl_ty_substs = if let ty::Projection(p) = predicate_self_ty.kind { + assert!( + p.item_def_id == trait_ty.def_id, + "projection_predicates returned predicate for the wrong type: {}", + predicate_self_ty, + ); + p.substs.rebase_onto(tcx, impl_trait_ref.def_id, impl_substs) + } else { + bug!( + "projection_predicates returned predicate for the wrong type `{}`", + predicate_self_ty, + ); + }; + impl_ty_value.subst(tcx, impl_ty_substs) + }; + + tcx.mk_substs( + iter::once(normalized_self.into()) + .chain(predicate_substs[1..].iter().map(|s| s.subst(tcx, impl_trait_ref.substs))), + ) + }; + + tcx.infer_ctxt().enter(move |infcx| { + let inh = Inherited::new(infcx, impl_ty.def_id.expect_local()); + let infcx = &inh.infcx; + let mut selcx = traits::SelectionContext::new(&infcx); + + let impl_ty_hir_id = tcx.hir().as_local_hir_id(impl_ty.def_id.expect_local()); + let normalize_cause = traits::ObligationCause::misc(impl_ty_span, impl_ty_hir_id); + let cause = ObligationCause::new( + impl_ty_span, + impl_ty_hir_id, + ObligationCauseCode::ItemObligation(trait_ty.def_id), + ); + + let predicates = tcx.projection_predicates(trait_ty.def_id); + + debug!("compare_projection_bounds: projection_predicates={:?}", predicates); + + for predicate in predicates { + let concrete_ty_predicate = match predicate.kind() { + ty::PredicateKind::Trait(poly_tr, c) => poly_tr + .map_bound(|tr| { + let trait_substs = translate_predicate_substs(tr.trait_ref.substs); + ty::TraitRef { def_id: tr.def_id(), substs: trait_substs } + }) + .with_constness(*c) + .to_predicate(tcx), + ty::PredicateKind::Projection(poly_projection) => poly_projection + .map_bound(|projection| { + let projection_substs = + translate_predicate_substs(projection.projection_ty.substs); + ty::ProjectionPredicate { + projection_ty: ty::ProjectionTy { + substs: projection_substs, + item_def_id: projection.projection_ty.item_def_id, + }, + ty: projection.ty.subst(tcx, impl_trait_ref.substs), + } + }) + .to_predicate(tcx), + _ => bug!("unexepected projection predicate kind: `{:?}`", predicate), + }; + + let traits::Normalized { value: normalized_predicate, obligations } = traits::normalize( + &mut selcx, + param_env, + normalize_cause.clone(), + &concrete_ty_predicate, + ); + + debug!("compare_projection_bounds: normalized predicate = {:?}", normalized_predicate); + + inh.register_predicates(obligations); + inh.register_predicate(traits::Obligation::new( + cause.clone(), + param_env, + normalized_predicate, + )); + } + + // Check that all obligations are satisfied by the implementation's + // version. + if let Err(ref errors) = inh.fulfillment_cx.borrow_mut().select_all_or_error(&infcx) { + infcx.report_fulfillment_errors(errors, None, false); + return Err(ErrorReported); + } + + // Finally, resolve all regions. This catches wily misuses of + // lifetime parameters. + let fcx = FnCtxt::new(&inh, param_env, impl_ty_hir_id); + fcx.regionck_item(impl_ty_hir_id, impl_ty_span, &[]); + + Ok(()) + }) +} + fn assoc_item_kind_str(impl_item: &ty::AssocItem) -> &'static str { match impl_item.kind { ty::AssocKind::Const => "const", diff --git a/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.rs b/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.rs new file mode 100644 index 0000000000000..71f9b2967dc58 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.rs @@ -0,0 +1,32 @@ +// Regression test for #68641 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait UnsafeCopy { + type Item<'a>: Copy; + + fn copy<'a>(item: &Self::Item<'a>) -> Self::Item<'a> { + *item + } +} + +impl UnsafeCopy for T { + type Item<'a> = T; + //~^ ERROR the trait bound `T: std::marker::Copy` is not satisfied +} + +fn main() { + let mut s = String::from("Hello world!"); + + let copy = String::copy(&s); + + // Do we indeed point to the samme memory? + assert!(s.as_ptr() == copy.as_ptr()); + + // Any use of `copy` is certeinly UB after this + drop(s); + + // UB UB UB UB UB!! + println!("{}", copy); +} diff --git a/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.stderr b/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.stderr new file mode 100644 index 0000000000000..eeff7c340ac96 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68641-check-gat-bounds.stderr @@ -0,0 +1,26 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68641-check-gat-bounds.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied + --> $DIR/issue-68641-check-gat-bounds.rs:15:5 + | +LL | trait UnsafeCopy { + | ---------------- required by `UnsafeCopy` +... +LL | type Item<'a> = T; + | ^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T` + | +help: consider restricting type parameter `T` + | +LL | impl UnsafeCopy for T { + | ^^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.rs b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.rs new file mode 100644 index 0000000000000..c99073c13284d --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.rs @@ -0,0 +1,21 @@ +// Regression test for #68642 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait Fun { + type F<'a>: Fn() -> u32; + + fn callme<'a>(f: Self::F<'a>) -> u32 { + f() + } +} + +impl Fun for T { + type F<'a> = Self; + //~^ ERROR expected a `std::ops::Fn<()>` closure, found `T` +} + +fn main() { + usize>::callme(|| 1); +} diff --git a/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr new file mode 100644 index 0000000000000..b3d4b8d465180 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68642-broken-llvm-ir.stderr @@ -0,0 +1,28 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68642-broken-llvm-ir.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0277]: expected a `std::ops::Fn<()>` closure, found `T` + --> $DIR/issue-68642-broken-llvm-ir.rs:15:5 + | +LL | trait Fun { + | --------- required by `Fun` +... +LL | type F<'a> = Self; + | ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T` + | + = help: the trait `std::ops::Fn<()>` is not implemented for `T` + = note: wrap the `T` in a closure with no arguments: `|| { /* code */ } +help: consider restricting type parameter `T` + | +LL | impl> Fun for T { + | ^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/generic-associated-types/issue-68643-broken-mir.rs b/src/test/ui/generic-associated-types/issue-68643-broken-mir.rs new file mode 100644 index 0000000000000..24133e75cccee --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68643-broken-mir.rs @@ -0,0 +1,21 @@ +// Regression test for #68643 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait Fun { + type F<'a>: Fn() -> u32; + + fn callme<'a>(f: Self::F<'a>) -> u32 { + f() + } +} + +impl Fun for T { + type F<'a> = Self; + //~^ ERROR expected a `std::ops::Fn<()>` closure, found `T` +} + +pub fn main() { + ::callme(|| {}); +} diff --git a/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr b/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr new file mode 100644 index 0000000000000..6e23fe02de8cd --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68643-broken-mir.stderr @@ -0,0 +1,28 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68643-broken-mir.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0277]: expected a `std::ops::Fn<()>` closure, found `T` + --> $DIR/issue-68643-broken-mir.rs:15:5 + | +LL | trait Fun { + | --------- required by `Fun` +... +LL | type F<'a> = Self; + | ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T` + | + = help: the trait `std::ops::Fn<()>` is not implemented for `T` + = note: wrap the `T` in a closure with no arguments: `|| { /* code */ } +help: consider restricting type parameter `T` + | +LL | impl> Fun for T { + | ^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/generic-associated-types/issue-68644-codegen-selection.rs b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.rs new file mode 100644 index 0000000000000..22620c61b8390 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.rs @@ -0,0 +1,21 @@ +// Regression test for #68644 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait Fun { + type F<'a>: Fn() -> u32; + + fn callme<'a>(f: Self::F<'a>) -> u32 { + f() + } +} + +impl Fun for T { + type F<'a> = Self; + //~^ ERROR expected a `std::ops::Fn<()>` closure, found `T` +} + +fn main() { + ::callme(0); +} diff --git a/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr new file mode 100644 index 0000000000000..234f5c8a0cc02 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68644-codegen-selection.stderr @@ -0,0 +1,28 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68644-codegen-selection.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0277]: expected a `std::ops::Fn<()>` closure, found `T` + --> $DIR/issue-68644-codegen-selection.rs:15:5 + | +LL | trait Fun { + | --------- required by `Fun` +... +LL | type F<'a> = Self; + | ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T` + | + = help: the trait `std::ops::Fn<()>` is not implemented for `T` + = note: wrap the `T` in a closure with no arguments: `|| { /* code */ } +help: consider restricting type parameter `T` + | +LL | impl> Fun for T { + | ^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.rs b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.rs new file mode 100644 index 0000000000000..423b80e8476f4 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.rs @@ -0,0 +1,21 @@ +// Regression test for #68645 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait Fun { + type F<'a>: Fn() -> u32; + + fn callme<'a>(f: Self::F<'a>) -> u32 { + f() + } +} + +impl Fun for T { + type F<'a> = Self; + //~^ ERROR expected a `std::ops::Fn<()>` closure, found `T` +} + +fn main() { + <&dyn Iterator>::callme(&std::iter::once(1)); +} diff --git a/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr new file mode 100644 index 0000000000000..ac2d5063fbb5d --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68645-codegen-fulfillment.stderr @@ -0,0 +1,28 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68645-codegen-fulfillment.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0277]: expected a `std::ops::Fn<()>` closure, found `T` + --> $DIR/issue-68645-codegen-fulfillment.rs:15:5 + | +LL | trait Fun { + | --------- required by `Fun` +... +LL | type F<'a> = Self; + | ^^^^^^^^^^^^^^^^^^ expected an `Fn<()>` closure, found `T` + | + = help: the trait `std::ops::Fn<()>` is not implemented for `T` + = note: wrap the `T` in a closure with no arguments: `|| { /* code */ } +help: consider restricting type parameter `T` + | +LL | impl> Fun for T { + | ^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/generic-associated-types/issue-68656-unsized-values.rs b/src/test/ui/generic-associated-types/issue-68656-unsized-values.rs new file mode 100644 index 0000000000000..4ccd42ba6432d --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68656-unsized-values.rs @@ -0,0 +1,22 @@ +// Regression test for #68656 + +#![feature(generic_associated_types)] +//~^ WARNING the feature `generic_associated_types` is incomplete and may not + +trait UnsafeCopy { + type Item<'a>: std::ops::Deref; + + fn bug<'a>(item: &Self::Item<'a>) -> () { + let x: T = **item; + &x as *const _; + } +} + +impl UnsafeCopy for T { + type Item<'a> = T; + //~^ ERROR type mismatch resolving `::Target == T` +} + +fn main() { + <&'static str>::bug(&""); +} diff --git a/src/test/ui/generic-associated-types/issue-68656-unsized-values.stderr b/src/test/ui/generic-associated-types/issue-68656-unsized-values.stderr new file mode 100644 index 0000000000000..e4eb7991f7637 --- /dev/null +++ b/src/test/ui/generic-associated-types/issue-68656-unsized-values.stderr @@ -0,0 +1,30 @@ +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/issue-68656-unsized-values.rs:3:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #44265 for more information + +error[E0271]: type mismatch resolving `::Target == T` + --> $DIR/issue-68656-unsized-values.rs:16:5 + | +LL | trait UnsafeCopy { + | ------------------------- required by `UnsafeCopy` +... +LL | impl UnsafeCopy for T { + | - this type parameter +LL | type Item<'a> = T; + | ^^^^^^^^^^^^^^^^^^ expected type parameter `T`, found associated type + | + = note: expected type parameter `T` + found associated type `::Target` +help: consider further restricting this bound + | +LL | impl> UnsafeCopy for T { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0271`. diff --git a/src/test/ui/issues/issue-38091.rs b/src/test/ui/issues/issue-38091.rs index c126243050244..a84391b94d1de 100644 --- a/src/test/ui/issues/issue-38091.rs +++ b/src/test/ui/issues/issue-38091.rs @@ -1,4 +1,3 @@ -// run-pass #![feature(specialization)] //~^ WARN the feature `specialization` is incomplete @@ -8,6 +7,7 @@ trait Iterate<'a> { } impl<'a, T> Iterate<'a> for T where T: Check { default type Ty = (); + //~^ ERROR the trait bound `(): Valid` is not satisfied default fn iterate(self) {} } diff --git a/src/test/ui/issues/issue-38091.stderr b/src/test/ui/issues/issue-38091.stderr index a9855445f6668..4d3369c5b6486 100644 --- a/src/test/ui/issues/issue-38091.stderr +++ b/src/test/ui/issues/issue-38091.stderr @@ -7,5 +7,15 @@ LL | #![feature(specialization)] = note: `#[warn(incomplete_features)]` on by default = note: see issue #31844 for more information -warning: 1 warning emitted +error[E0277]: the trait bound `(): Valid` is not satisfied + --> $DIR/issue-38091.rs:8:5 + | +LL | trait Iterate<'a> { + | ----------------- required by `Iterate` +... +LL | default type Ty = (); + | ^^^^^^^^^^^^^^^^^^^^^ the trait `Valid` is not implemented for `()` + +error: aborting due to previous error +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/specialization/deafult-associated-type-bound-1.rs b/src/test/ui/specialization/deafult-associated-type-bound-1.rs new file mode 100644 index 0000000000000..272a5e3fe10c6 --- /dev/null +++ b/src/test/ui/specialization/deafult-associated-type-bound-1.rs @@ -0,0 +1,24 @@ +// Check that we check that default associated types satisfy the required +// bounds on them. + +#![feature(specialization)] +//~^ WARNING `specialization` is incomplete + +trait X { + type U: Clone; + fn unsafe_clone(&self, x: Option<&Self::U>) { + x.cloned(); + } +} + +// We cannot normalize `::U` to `str` here, because the default could +// be overridden. The error here must therefore be found by a method other than +// normalization. +impl X for T { + default type U = str; + //~^ ERROR the trait bound `str: std::clone::Clone` is not satisfied +} + +pub fn main() { + 1.unsafe_clone(None); +} diff --git a/src/test/ui/specialization/deafult-associated-type-bound-1.stderr b/src/test/ui/specialization/deafult-associated-type-bound-1.stderr new file mode 100644 index 0000000000000..8b3d6a913a7a0 --- /dev/null +++ b/src/test/ui/specialization/deafult-associated-type-bound-1.stderr @@ -0,0 +1,21 @@ +warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/deafult-associated-type-bound-1.rs:4:12 + | +LL | #![feature(specialization)] + | ^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #31844 for more information + +error[E0277]: the trait bound `str: std::clone::Clone` is not satisfied + --> $DIR/deafult-associated-type-bound-1.rs:18:5 + | +LL | trait X { + | ------- required by `X` +... +LL | default type U = str; + | ^^^^^^^^^^^^^^^^^^^^^ the trait `std::clone::Clone` is not implemented for `str` + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/specialization/deafult-associated-type-bound-2.rs b/src/test/ui/specialization/deafult-associated-type-bound-2.rs new file mode 100644 index 0000000000000..0a21b1f09106b --- /dev/null +++ b/src/test/ui/specialization/deafult-associated-type-bound-2.rs @@ -0,0 +1,22 @@ +// Check that generic predicates are also checked for default associated types. +#![feature(specialization)] +//~^ WARNING `specialization` is incomplete + +trait X { + type U: PartialEq; + fn unsafe_compare(x: Option, y: Option) { + match (x, y) { + (Some(a), Some(b)) => a == b, + _ => false, + }; + } +} + +impl X for T { + default type U = &'static B; + //~^ ERROR can't compare `&'static B` with `B` +} + +pub fn main() { + >::unsafe_compare(None, None); +} diff --git a/src/test/ui/specialization/deafult-associated-type-bound-2.stderr b/src/test/ui/specialization/deafult-associated-type-bound-2.stderr new file mode 100644 index 0000000000000..4d21f47051fab --- /dev/null +++ b/src/test/ui/specialization/deafult-associated-type-bound-2.stderr @@ -0,0 +1,23 @@ +warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/deafult-associated-type-bound-2.rs:2:12 + | +LL | #![feature(specialization)] + | ^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #31844 for more information + +error[E0277]: can't compare `&'static B` with `B` + --> $DIR/deafult-associated-type-bound-2.rs:16:5 + | +LL | trait X { + | ---------- required by `X` +... +LL | default type U = &'static B; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `&'static B == B` + | + = help: the trait `std::cmp::PartialEq` is not implemented for `&'static B` + +error: aborting due to previous error; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/specialization/deafult-generic-associated-type-bound.rs b/src/test/ui/specialization/deafult-generic-associated-type-bound.rs new file mode 100644 index 0000000000000..8a94ea658d2d0 --- /dev/null +++ b/src/test/ui/specialization/deafult-generic-associated-type-bound.rs @@ -0,0 +1,27 @@ +// Check that default generics associated types are validated. + +#![feature(specialization)] +#![feature(generic_associated_types)] +//~^^ WARNING `specialization` is incomplete +//~^^ WARNING the feature `generic_associated_types` is incomplete + +trait X { + type U<'a>: PartialEq<&'a Self>; + fn unsafe_compare<'b>(x: Option>, y: Option<&'b Self>) { + match (x, y) { + (Some(a), Some(b)) => a == b, + _ => false, + }; + } +} + +impl X for T { + default type U<'a> = &'a T; + //~^ ERROR can't compare `T` with `T` +} + +struct NotComparable; + +pub fn main() { + ::unsafe_compare(None, None); +} diff --git a/src/test/ui/specialization/deafult-generic-associated-type-bound.stderr b/src/test/ui/specialization/deafult-generic-associated-type-bound.stderr new file mode 100644 index 0000000000000..1aac9e70d87d8 --- /dev/null +++ b/src/test/ui/specialization/deafult-generic-associated-type-bound.stderr @@ -0,0 +1,36 @@ +warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/deafult-generic-associated-type-bound.rs:3:12 + | +LL | #![feature(specialization)] + | ^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + = note: see issue #31844 for more information + +warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/deafult-generic-associated-type-bound.rs:4:12 + | +LL | #![feature(generic_associated_types)] + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: see issue #44265 for more information + +error[E0277]: can't compare `T` with `T` + --> $DIR/deafult-generic-associated-type-bound.rs:19:5 + | +LL | trait X { + | ------- required by `X` +... +LL | default type U<'a> = &'a T; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `T == T` + | + = help: the trait `std::cmp::PartialEq` is not implemented for `T` + = note: required because of the requirements on the impl of `for<'a> std::cmp::PartialEq` for `&'a T` +help: consider further restricting this bound + | +LL | impl X for T { + | ^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error; 2 warnings emitted + +For more information about this error, try `rustc --explain E0277`.