diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs index 9eb91569ed5..b7c7fd4729f 100644 --- a/src/librustc/traits/error_reporting.rs +++ b/src/librustc/traits/error_reporting.rs @@ -715,8 +715,11 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { // these notes will often be of the form // "the type `T` can't be frobnicated" // which is somewhat confusing. - err.help(&format!("consider adding a `where {}` bound", - trait_ref.to_predicate())); + self.suggest_restricting_param_bound( + &mut err, + &trait_ref, + obligation.cause.body_id, + ); } else { if !have_alt_message { // Can't show anything else useful, try to find similar impls. @@ -960,6 +963,96 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { err.emit(); } + fn suggest_restricting_param_bound( + &self, + err: &mut DiagnosticBuilder<'_>, + trait_ref: &ty::PolyTraitRef<'_>, + body_id: hir::HirId, + ) { + let node = self.tcx.hir().find(self.tcx.hir().get_parent_item(body_id)); + if let ty::Param(param_ty) = &trait_ref.self_ty().kind { + let restrict_msg = "consider further restricting this bound"; + let param_name = param_ty.name.as_str(); + + if let Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Struct(_, generics), span, .. + })) | + Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Enum(_, generics), span, .. + })) | + Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Union(_, generics), span, .. + })) | + Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Trait(_, _, generics, ..), span, .. + })) | + Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Impl(_, _, _, generics, ..), span, .. + })) | + Some(hir::Node::Item(hir::Item { + kind: hir::ItemKind::Fn(_, _, generics, _), span, .. + })) = &node { + for param in &generics.params { + if param_name == param.name.ident().as_str() { + if param_name.starts_with("impl ") { + err.span_suggestion( + param.span, + restrict_msg, + // `impl CurrentTrait + MissingTrait` + format!("{} + {}", param.name.ident(), trait_ref), + Applicability::MachineApplicable, + ); + } else { + if generics.where_clause.predicates.is_empty() && + param.bounds.is_empty() + { + err.span_suggestion( + param.span, + "consider restricting this bound", + format!("{}", trait_ref.to_predicate()), + Applicability::MachineApplicable, + ); + } else if !generics.where_clause.predicates.is_empty() { + err.span_suggestion( + generics.where_clause.span().unwrap().shrink_to_hi(), + &format!( + "consider further restricting type parameter `{}`", + param_ty, + ), + format!(", {}", trait_ref.to_predicate()), + Applicability::MachineApplicable, + ); + } else { + let sp = param.span.with_hi(span.hi()); + let span = self.tcx.sess.source_map().span_through_char(sp, ':'); + if sp != param.span && sp != span { + // Only suggest if we have high certainty that the span covers + // the colon in `foo`. + err.span_suggestion(span, restrict_msg, format!( + "{} + ", + trait_ref.to_predicate(), + ), Applicability::MachineApplicable); + } else { + err.span_label(param.span, &format!( + "consider adding a `where {}` bound", + trait_ref.to_predicate(), + )); + } + } + } + return; + } + } + } + } + // FIXME: Add special check for `?Sized` so we don't suggest `T: Sized + ?Sized`. + + // Fallback in case we didn't find the type argument. Can happen on associated types + // bounds and when `Self` needs to be restricted, like in the ui test + // `associated-types-projection-to-unrelated-trait-in-method-without-default.rs`. + err.help(&format!("consider adding a `where {}` bound", trait_ref.to_predicate())); + } + /// When encountering an assignment of an unsized trait, like `let x = ""[..];`, provide a /// suggestion to borrow the initializer in order to use have a slice instead. fn suggest_borrow_on_unsized_slice( diff --git a/src/test/ui/associated-const/associated-const-type-parameter-arrays-2.stderr b/src/test/ui/associated-const/associated-const-type-parameter-arrays-2.stderr index 30b6b4f3909..c258892057b 100644 --- a/src/test/ui/associated-const/associated-const-type-parameter-arrays-2.stderr +++ b/src/test/ui/associated-const/associated-const-type-parameter-arrays-2.stderr @@ -4,10 +4,10 @@ error[E0277]: the trait bound `A: Foo` is not satisfied LL | const Y: usize; | --------------- required by `Foo::Y` ... +LL | pub fn test() { + | -- help: consider further restricting this bound: `A: Foo +` LL | let _array = [4; ::Y]; | ^^^^^^^^^^^^^ the trait `Foo` is not implemented for `A` - | - = help: consider adding a `where A: Foo` bound error: aborting due to previous error diff --git a/src/test/ui/associated-const/associated-const-type-parameter-arrays.stderr b/src/test/ui/associated-const/associated-const-type-parameter-arrays.stderr index 30fa9891a13..f6c8e99e27a 100644 --- a/src/test/ui/associated-const/associated-const-type-parameter-arrays.stderr +++ b/src/test/ui/associated-const/associated-const-type-parameter-arrays.stderr @@ -4,10 +4,10 @@ error[E0277]: the trait bound `A: Foo` is not satisfied LL | const Y: usize; | --------------- required by `Foo::Y` ... +LL | pub fn test() { + | -- help: consider further restricting this bound: `A: Foo +` LL | let _array: [u32; ::Y]; | ^^^^^^^^^^^^^ the trait `Foo` is not implemented for `A` - | - = help: consider adding a `where A: Foo` bound error: aborting due to previous error diff --git a/src/test/ui/associated-types/associated-types-invalid-trait-ref-issue-18865.stderr b/src/test/ui/associated-types/associated-types-invalid-trait-ref-issue-18865.stderr index 01f66a18d25..0b8b7fab135 100644 --- a/src/test/ui/associated-types/associated-types-invalid-trait-ref-issue-18865.stderr +++ b/src/test/ui/associated-types/associated-types-invalid-trait-ref-issue-18865.stderr @@ -1,10 +1,10 @@ error[E0277]: the trait bound `T: Foo` is not satisfied --> $DIR/associated-types-invalid-trait-ref-issue-18865.rs:10:12 | +LL | fn f>(t: &T) { + | -- help: consider further restricting this bound: `T: Foo +` LL | let u: >::Bar = t.get_bar(); | ^^^^^^^^^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `T` - | - = help: consider adding a `where T: Foo` bound error: aborting due to previous error diff --git a/src/test/ui/bad/bad-method-typaram-kind.stderr b/src/test/ui/bad/bad-method-typaram-kind.stderr index c72b9652360..740667f1466 100644 --- a/src/test/ui/bad/bad-method-typaram-kind.stderr +++ b/src/test/ui/bad/bad-method-typaram-kind.stderr @@ -1,11 +1,12 @@ error[E0277]: `T` cannot be sent between threads safely --> $DIR/bad-method-typaram-kind.rs:2:7 | +LL | fn foo() { + | -- help: consider further restricting this bound: `T: std::marker::Send +` LL | 1.bar::(); | ^^^ `T` cannot be sent between threads safely | = help: the trait `std::marker::Send` is not implemented for `T` - = help: consider adding a `where T: std::marker::Send` bound error: aborting due to previous error diff --git a/src/test/ui/closures/closure-bounds-subtype.stderr b/src/test/ui/closures/closure-bounds-subtype.stderr index 4b703eded69..05d5bb1e8d5 100644 --- a/src/test/ui/closures/closure-bounds-subtype.stderr +++ b/src/test/ui/closures/closure-bounds-subtype.stderr @@ -4,11 +4,13 @@ error[E0277]: `F` cannot be shared between threads safely LL | fn take_const_owned(_: F) where F: FnOnce() + Sync + Send { | ---------------- ---- required by this bound in `take_const_owned` ... +LL | fn give_owned(f: F) where F: FnOnce() + Send { + | - help: consider further restricting type parameter `F`: `, F: std::marker::Sync` +LL | take_any(f); LL | take_const_owned(f); | ^ `F` cannot be shared between threads safely | = help: the trait `std::marker::Sync` is not implemented for `F` - = help: consider adding a `where F: std::marker::Sync` bound error: aborting due to previous error diff --git a/src/test/ui/dst/dst-object-from-unsized-type.stderr b/src/test/ui/dst/dst-object-from-unsized-type.stderr index 55ac625fc98..40db575eabd 100644 --- a/src/test/ui/dst/dst-object-from-unsized-type.stderr +++ b/src/test/ui/dst/dst-object-from-unsized-type.stderr @@ -1,23 +1,25 @@ error[E0277]: the size for values of type `T` cannot be known at compilation time --> $DIR/dst-object-from-unsized-type.rs:8:23 | +LL | fn test1(t: &T) { + | -- help: consider further restricting this bound: `T: std::marker::Sized +` LL | let u: &dyn Foo = t; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound = note: required for the cast to the object type `dyn Foo` error[E0277]: the size for values of type `T` cannot be known at compilation time --> $DIR/dst-object-from-unsized-type.rs:13:23 | +LL | fn test2(t: &T) { + | -- help: consider further restricting this bound: `T: std::marker::Sized +` LL | let v: &dyn Foo = t as &dyn Foo; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound = note: required for the cast to the object type `dyn Foo` error[E0277]: the size for values of type `str` cannot be known at compilation time diff --git a/src/test/ui/hrtb/hrtb-higher-ranker-supertraits-transitive.stderr b/src/test/ui/hrtb/hrtb-higher-ranker-supertraits-transitive.stderr index c2cc8ebad27..afcb467ad47 100644 --- a/src/test/ui/hrtb/hrtb-higher-ranker-supertraits-transitive.stderr +++ b/src/test/ui/hrtb/hrtb-higher-ranker-supertraits-transitive.stderr @@ -6,10 +6,11 @@ LL | fn want_bar_for_any_ccx(b: &B) LL | where B : for<'ccx> Bar<'ccx> | ------------------- required by this bound in `want_bar_for_any_ccx` ... +LL | where B : Qux + | - help: consider further restricting type parameter `B`: `, for<'ccx> B: Bar<'ccx>` +... LL | want_bar_for_any_ccx(b); | ^ the trait `for<'ccx> Bar<'ccx>` is not implemented for `B` - | - = help: consider adding a `where for<'ccx> B: Bar<'ccx>` bound error: aborting due to previous error diff --git a/src/test/ui/hrtb/hrtb-higher-ranker-supertraits.stderr b/src/test/ui/hrtb/hrtb-higher-ranker-supertraits.stderr index a93814ad4c2..20913b4f28c 100644 --- a/src/test/ui/hrtb/hrtb-higher-ranker-supertraits.stderr +++ b/src/test/ui/hrtb/hrtb-higher-ranker-supertraits.stderr @@ -1,6 +1,9 @@ error[E0277]: the trait bound `for<'tcx> F: Foo<'tcx>` is not satisfied --> $DIR/hrtb-higher-ranker-supertraits.rs:18:26 | +LL | where F : Foo<'x> + | - help: consider further restricting type parameter `F`: `, for<'tcx> F: Foo<'tcx>` +... LL | want_foo_for_any_tcx(f); | ^ the trait `for<'tcx> Foo<'tcx>` is not implemented for `F` ... @@ -8,12 +11,13 @@ LL | fn want_foo_for_any_tcx(f: &F) | -------------------- LL | where F : for<'tcx> Foo<'tcx> | ------------------- required by this bound in `want_foo_for_any_tcx` - | - = help: consider adding a `where for<'tcx> F: Foo<'tcx>` bound error[E0277]: the trait bound `for<'ccx> B: Bar<'ccx>` is not satisfied --> $DIR/hrtb-higher-ranker-supertraits.rs:35:26 | +LL | where B : Bar<'x> + | - help: consider further restricting type parameter `B`: `, for<'ccx> B: Bar<'ccx>` +... LL | want_bar_for_any_ccx(b); | ^ the trait `for<'ccx> Bar<'ccx>` is not implemented for `B` ... @@ -21,8 +25,6 @@ LL | fn want_bar_for_any_ccx(b: &B) | -------------------- LL | where B : for<'ccx> Bar<'ccx> | ------------------- required by this bound in `want_bar_for_any_ccx` - | - = help: consider adding a `where for<'ccx> B: Bar<'ccx>` bound error: aborting due to 2 previous errors diff --git a/src/test/ui/kindck/kindck-impl-type-params.stderr b/src/test/ui/kindck/kindck-impl-type-params.stderr index e6f7088bd46..777a553c2a5 100644 --- a/src/test/ui/kindck/kindck-impl-type-params.stderr +++ b/src/test/ui/kindck/kindck-impl-type-params.stderr @@ -1,42 +1,50 @@ error[E0277]: `T` cannot be sent between threads safely --> $DIR/kindck-impl-type-params.rs:18:13 | +LL | fn f(val: T) { + | - help: consider restricting this bound: `T: std::marker::Send` +LL | let t: S = S(marker::PhantomData); LL | let a = &t as &dyn Gettable; | ^^ `T` cannot be sent between threads safely | = help: the trait `std::marker::Send` is not implemented for `T` - = help: consider adding a `where T: std::marker::Send` bound = note: required because of the requirements on the impl of `Gettable` for `S` = note: required for the cast to the object type `dyn Gettable` error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied --> $DIR/kindck-impl-type-params.rs:18:13 | +LL | fn f(val: T) { + | - help: consider restricting this bound: `T: std::marker::Copy` +LL | let t: S = S(marker::PhantomData); LL | let a = &t as &dyn Gettable; | ^^ the trait `std::marker::Copy` is not implemented for `T` | - = help: consider adding a `where T: std::marker::Copy` bound = note: required because of the requirements on the impl of `Gettable` for `S` = note: required for the cast to the object type `dyn Gettable` error[E0277]: `T` cannot be sent between threads safely --> $DIR/kindck-impl-type-params.rs:25:31 | +LL | fn g(val: T) { + | - help: consider restricting this bound: `T: std::marker::Send` +LL | let t: S = S(marker::PhantomData); LL | let a: &dyn Gettable = &t; | ^^ `T` cannot be sent between threads safely | = help: the trait `std::marker::Send` is not implemented for `T` - = help: consider adding a `where T: std::marker::Send` bound = note: required because of the requirements on the impl of `Gettable` for `S` = note: required for the cast to the object type `dyn Gettable` error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied --> $DIR/kindck-impl-type-params.rs:25:31 | +LL | fn g(val: T) { + | - help: consider restricting this bound: `T: std::marker::Copy` +LL | let t: S = S(marker::PhantomData); LL | let a: &dyn Gettable = &t; | ^^ the trait `std::marker::Copy` is not implemented for `T` | - = help: consider adding a `where T: std::marker::Copy` bound = note: required because of the requirements on the impl of `Gettable` for `S` = note: required for the cast to the object type `dyn Gettable` diff --git a/src/test/ui/phantom-oibit.stderr b/src/test/ui/phantom-oibit.stderr index ac48ee0cb0f..4d9d06b8986 100644 --- a/src/test/ui/phantom-oibit.stderr +++ b/src/test/ui/phantom-oibit.stderr @@ -3,12 +3,13 @@ error[E0277]: `T` cannot be shared between threads safely | LL | fn is_zen(_: T) {} | ------ --- required by this bound in `is_zen` -... +LL | +LL | fn not_sync(x: Guard) { + | - help: consider restricting this bound: `T: std::marker::Sync` LL | is_zen(x) | ^ `T` cannot be shared between threads safely | = help: the trait `std::marker::Sync` is not implemented for `T` - = help: consider adding a `where T: std::marker::Sync` bound = note: required because of the requirements on the impl of `Zen` for `&T` = note: required because it appears within the type `std::marker::PhantomData<&T>` = note: required because it appears within the type `Guard<'_, T>` @@ -19,11 +20,12 @@ error[E0277]: `T` cannot be shared between threads safely LL | fn is_zen(_: T) {} | ------ --- required by this bound in `is_zen` ... +LL | fn nested_not_sync(x: Nested>) { + | - help: consider restricting this bound: `T: std::marker::Sync` LL | is_zen(x) | ^ `T` cannot be shared between threads safely | = help: the trait `std::marker::Sync` is not implemented for `T` - = help: consider adding a `where T: std::marker::Sync` bound = note: required because of the requirements on the impl of `Zen` for `&T` = note: required because it appears within the type `std::marker::PhantomData<&T>` = note: required because it appears within the type `Guard<'_, T>` diff --git a/src/test/ui/suggestions/restrict-type-argument.rs b/src/test/ui/suggestions/restrict-type-argument.rs new file mode 100644 index 00000000000..c4ebfbe922c --- /dev/null +++ b/src/test/ui/suggestions/restrict-type-argument.rs @@ -0,0 +1,31 @@ +fn is_send(val: T) {} + +fn use_impl_sync(val: impl Sync) { + is_send(val); //~ ERROR `impl Sync` cannot be sent between threads safely +} + +fn use_where(val: S) where S: Sync { + is_send(val); //~ ERROR `S` cannot be sent between threads safely +} + +fn use_bound(val: S) { + is_send(val); //~ ERROR `S` cannot be sent between threads safely +} + +fn use_bound_2< + S // Make sure we can synthezise a correct suggestion span for this case + : + Sync +>(val: S) { + is_send(val); //~ ERROR `S` cannot be sent between threads safely +} + +fn use_bound_and_where(val: S) where S: std::fmt::Debug { + is_send(val); //~ ERROR `S` cannot be sent between threads safely +} + +fn use_unbound(val: S) { + is_send(val); //~ ERROR `S` cannot be sent between threads safely +} + +fn main() {} diff --git a/src/test/ui/suggestions/restrict-type-argument.stderr b/src/test/ui/suggestions/restrict-type-argument.stderr new file mode 100644 index 00000000000..d6840ca4d72 --- /dev/null +++ b/src/test/ui/suggestions/restrict-type-argument.stderr @@ -0,0 +1,83 @@ +error[E0277]: `impl Sync` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:4:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +LL | +LL | fn use_impl_sync(val: impl Sync) { + | --------- help: consider further restricting this bound: `impl Sync + std::marker::Send` +LL | is_send(val); + | ^^^ `impl Sync` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `impl Sync` + +error[E0277]: `S` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:8:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +... +LL | fn use_where(val: S) where S: Sync { + | - help: consider further restricting type parameter `S`: `, S: std::marker::Send` +LL | is_send(val); + | ^^^ `S` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `S` + +error[E0277]: `S` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:12:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +... +LL | fn use_bound(val: S) { + | -- help: consider further restricting this bound: `S: std::marker::Send +` +LL | is_send(val); + | ^^^ `S` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `S` + +error[E0277]: `S` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:20:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +... +LL | / S // Make sure we can synthezise a correct suggestion span for this case +LL | | : + | |_____- help: consider further restricting this bound: `S: std::marker::Send +` +... +LL | is_send(val); + | ^^^ `S` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `S` + +error[E0277]: `S` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:24:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +... +LL | fn use_bound_and_where(val: S) where S: std::fmt::Debug { + | - help: consider further restricting type parameter `S`: `, S: std::marker::Send` +LL | is_send(val); + | ^^^ `S` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `S` + +error[E0277]: `S` cannot be sent between threads safely + --> $DIR/restrict-type-argument.rs:28:13 + | +LL | fn is_send(val: T) {} + | ------- ---- required by this bound in `is_send` +... +LL | fn use_unbound(val: S) { + | - help: consider restricting this bound: `S: std::marker::Send` +LL | is_send(val); + | ^^^ `S` cannot be sent between threads safely + | + = help: the trait `std::marker::Send` is not implemented for `S` + +error: aborting due to 6 previous errors + +For more information about this error, try `rustc --explain E0277`. diff --git a/src/test/ui/traits/trait-suggest-where-clause.stderr b/src/test/ui/traits/trait-suggest-where-clause.stderr index d15edaa9c81..bc9948064a3 100644 --- a/src/test/ui/traits/trait-suggest-where-clause.stderr +++ b/src/test/ui/traits/trait-suggest-where-clause.stderr @@ -1,6 +1,9 @@ error[E0277]: the size for values of type `U` cannot be known at compilation time --> $DIR/trait-suggest-where-clause.rs:9:20 | +LL | fn check() { + | -- help: consider further restricting this bound: `U: std::marker::Sized +` +LL | // suggest a where-clause, if needed LL | mem::size_of::(); | ^ doesn't have a size known at compile-time | @@ -11,11 +14,13 @@ LL | pub const fn size_of() -> usize { | = help: the trait `std::marker::Sized` is not implemented for `U` = note: to learn more, visit - = help: consider adding a `where U: std::marker::Sized` bound error[E0277]: the size for values of type `U` cannot be known at compilation time --> $DIR/trait-suggest-where-clause.rs:12:5 | +LL | fn check() { + | -- help: consider further restricting this bound: `U: std::marker::Sized +` +... LL | mem::size_of::>(); | ^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time | @@ -26,7 +31,6 @@ LL | pub const fn size_of() -> usize { | = help: within `Misc`, the trait `std::marker::Sized` is not implemented for `U` = note: to learn more, visit - = help: consider adding a `where U: std::marker::Sized` bound = note: required because it appears within the type `Misc` error[E0277]: the trait bound `u64: std::convert::From` is not satisfied diff --git a/src/test/ui/traits/traits-repeated-supertrait-ambig.stderr b/src/test/ui/traits/traits-repeated-supertrait-ambig.stderr index db77e82adbd..85c7a55c313 100644 --- a/src/test/ui/traits/traits-repeated-supertrait-ambig.stderr +++ b/src/test/ui/traits/traits-repeated-supertrait-ambig.stderr @@ -7,10 +7,10 @@ LL | c.same_as(22) error[E0277]: the trait bound `C: CompareTo` is not satisfied --> $DIR/traits-repeated-supertrait-ambig.rs:30:7 | +LL | fn with_trait(c: &C) -> bool { + | -- help: consider further restricting this bound: `C: CompareTo +` LL | c.same_as(22) | ^^^^^^^ the trait `CompareTo` is not implemented for `C` - | - = help: consider adding a `where C: CompareTo` bound error[E0277]: the trait bound `dyn CompareToInts: CompareTo` is not satisfied --> $DIR/traits-repeated-supertrait-ambig.rs:34:5 @@ -27,10 +27,10 @@ error[E0277]: the trait bound `C: CompareTo` is not satisfied LL | fn same_as(&self, t: T) -> bool; | -------------------------------- required by `CompareTo::same_as` ... +LL | fn with_ufcs2(c: &C) -> bool { + | -- help: consider further restricting this bound: `C: CompareTo +` LL | CompareTo::same_as(c, 22) | ^^^^^^^^^^^^^^^^^^ the trait `CompareTo` is not implemented for `C` - | - = help: consider adding a `where C: CompareTo` bound error[E0277]: the trait bound `i64: CompareTo` is not satisfied --> $DIR/traits-repeated-supertrait-ambig.rs:42:23 diff --git a/src/test/ui/type-alias-impl-trait/generic_underconstrained.stderr b/src/test/ui/type-alias-impl-trait/generic_underconstrained.stderr index dd90dd1b06f..63c07224353 100644 --- a/src/test/ui/type-alias-impl-trait/generic_underconstrained.stderr +++ b/src/test/ui/type-alias-impl-trait/generic_underconstrained.stderr @@ -9,8 +9,10 @@ error[E0277]: the trait bound `T: Trait` is not satisfied | LL | type Underconstrained = impl 'static; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Trait` is not implemented for `T` +... +LL | fn underconstrain(_: T) -> Underconstrained { + | - help: consider restricting this bound: `T: Trait` | - = help: consider adding a `where T: Trait` bound = note: the return type of a function must have a statically known size error: aborting due to 2 previous errors diff --git a/src/test/ui/type-alias-impl-trait/generic_underconstrained2.stderr b/src/test/ui/type-alias-impl-trait/generic_underconstrained2.stderr index 574432bdcf6..ba892f6ed7c 100644 --- a/src/test/ui/type-alias-impl-trait/generic_underconstrained2.stderr +++ b/src/test/ui/type-alias-impl-trait/generic_underconstrained2.stderr @@ -15,9 +15,11 @@ error[E0277]: `U` doesn't implement `std::fmt::Debug` | LL | type Underconstrained = impl 'static; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `U` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug` +... +LL | fn underconstrained(_: U) -> Underconstrained { + | - help: consider restricting this bound: `U: std::fmt::Debug` | = help: the trait `std::fmt::Debug` is not implemented for `U` - = help: consider adding a `where U: std::fmt::Debug` bound = note: the return type of a function must have a statically known size error[E0277]: `V` doesn't implement `std::fmt::Debug` @@ -25,9 +27,11 @@ error[E0277]: `V` doesn't implement `std::fmt::Debug` | LL | type Underconstrained2 = impl 'static; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `V` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug` +... +LL | fn underconstrained2(_: U, _: V) -> Underconstrained2 { + | - help: consider restricting this bound: `V: std::fmt::Debug` | = help: the trait `std::fmt::Debug` is not implemented for `V` - = help: consider adding a `where V: std::fmt::Debug` bound = note: the return type of a function must have a statically known size error: aborting due to 4 previous errors diff --git a/src/test/ui/typeck/typeck-default-trait-impl-send-param.stderr b/src/test/ui/typeck/typeck-default-trait-impl-send-param.stderr index b3139083b1a..a84aef5fdbd 100644 --- a/src/test/ui/typeck/typeck-default-trait-impl-send-param.stderr +++ b/src/test/ui/typeck/typeck-default-trait-impl-send-param.stderr @@ -1,6 +1,8 @@ error[E0277]: `T` cannot be sent between threads safely --> $DIR/typeck-default-trait-impl-send-param.rs:5:15 | +LL | fn foo() { + | - help: consider restricting this bound: `T: std::marker::Send` LL | is_send::() | ^ `T` cannot be sent between threads safely ... @@ -8,7 +10,6 @@ LL | fn is_send() { | ------- ---- required by this bound in `is_send` | = help: the trait `std::marker::Send` is not implemented for `T` - = help: consider adding a `where T: std::marker::Send` bound error: aborting due to previous error diff --git a/src/test/ui/unsized/unsized-bare-typaram.stderr b/src/test/ui/unsized/unsized-bare-typaram.stderr index e56176690a1..bd97b0203b5 100644 --- a/src/test/ui/unsized/unsized-bare-typaram.stderr +++ b/src/test/ui/unsized/unsized-bare-typaram.stderr @@ -4,11 +4,12 @@ error[E0277]: the size for values of type `T` cannot be known at compilation tim LL | fn bar() { } | --- - required by this bound in `bar` LL | fn foo() { bar::() } - | ^ doesn't have a size known at compile-time + | -- ^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `T: std::marker::Sized +` | = help: the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound error: aborting due to previous error diff --git a/src/test/ui/unsized/unsized-enum.stderr b/src/test/ui/unsized/unsized-enum.stderr index dff934834ef..341d3e4cc2d 100644 --- a/src/test/ui/unsized/unsized-enum.stderr +++ b/src/test/ui/unsized/unsized-enum.stderr @@ -5,11 +5,12 @@ LL | enum Foo { FooSome(U), FooNone } | ----------- required by `Foo` LL | fn foo1() { not_sized::>() } // Hunky dory. LL | fn foo2() { not_sized::>() } - | ^^^^^^ doesn't have a size known at compile-time + | -- ^^^^^^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `T: std::marker::Sized +` | = help: the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound error: aborting due to previous error diff --git a/src/test/ui/unsized/unsized-struct.stderr b/src/test/ui/unsized/unsized-struct.stderr index 0d4776ff6c2..2894d5d5671 100644 --- a/src/test/ui/unsized/unsized-struct.stderr +++ b/src/test/ui/unsized/unsized-struct.stderr @@ -5,11 +5,12 @@ LL | struct Foo { data: T } | ------------- required by `Foo` LL | fn foo1() { not_sized::>() } // Hunky dory. LL | fn foo2() { not_sized::>() } - | ^^^^^^ doesn't have a size known at compile-time + | -- ^^^^^^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `T: std::marker::Sized +` | = help: the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound error[E0277]: the size for values of type `T` cannot be known at compilation time --> $DIR/unsized-struct.rs:13:24 @@ -18,11 +19,12 @@ LL | fn is_sized() { } | -------- - required by this bound in `is_sized` ... LL | fn bar2() { is_sized::>() } - | ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time + | -- ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `T: std::marker::Sized +` | = help: within `Bar`, the trait `std::marker::Sized` is not implemented for `T` = note: to learn more, visit - = help: consider adding a `where T: std::marker::Sized` bound = note: required because it appears within the type `Bar` error: aborting due to 2 previous errors diff --git a/src/test/ui/unsized3.stderr b/src/test/ui/unsized3.stderr index c821a08f6b5..232296ad091 100644 --- a/src/test/ui/unsized3.stderr +++ b/src/test/ui/unsized3.stderr @@ -1,6 +1,8 @@ error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized3.rs:7:13 | +LL | fn f1(x: &X) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f2::(x); | ^ doesn't have a size known at compile-time ... @@ -9,11 +11,12 @@ LL | fn f2(x: &X) { | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized3.rs:18:13 | +LL | fn f3(x: &X) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f4::(x); | ^ doesn't have a size known at compile-time ... @@ -22,7 +25,6 @@ LL | fn f4(x: &X) { | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized3.rs:33:8 @@ -30,35 +32,38 @@ error[E0277]: the size for values of type `X` cannot be known at compilation tim LL | fn f5(x: &Y) {} | -- - required by this bound in `f5` ... +LL | fn f8(x1: &S, x2: &S) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f5(x1); | ^^ doesn't have a size known at compile-time | = help: within `S`, the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: required because it appears within the type `S` error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized3.rs:40:8 | +LL | fn f9(x1: Box>) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f5(&(*x1, 34)); | ^^^^^^^^^^ doesn't have a size known at compile-time | = help: within `S`, the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: required because it appears within the type `S` = note: only the last element of a tuple may have a dynamically sized type error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized3.rs:45:9 | +LL | fn f10(x1: Box>) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f5(&(32, *x1)); | ^^^^^^^^^ doesn't have a size known at compile-time | = help: within `({integer}, S)`, the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: required because it appears within the type `S` = note: required because it appears within the type `({integer}, S)` = note: tuples must have a statically known size to be initialized @@ -69,12 +74,13 @@ error[E0277]: the size for values of type `X` cannot be known at compilation tim LL | fn f5(x: &Y) {} | -- - required by this bound in `f5` ... +LL | fn f10(x1: Box>) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | f5(&(32, *x1)); | ^^^^^^^^^^ doesn't have a size known at compile-time | = help: within `({integer}, S)`, the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: required because it appears within the type `S` = note: required because it appears within the type `({integer}, S)` diff --git a/src/test/ui/unsized6.stderr b/src/test/ui/unsized6.stderr index a6a26573e7c..95acd987a5a 100644 --- a/src/test/ui/unsized6.stderr +++ b/src/test/ui/unsized6.stderr @@ -1,129 +1,148 @@ error[E0277]: the size for values of type `Y` cannot be known at compilation time --> $DIR/unsized6.rs:9:9 | +LL | fn f1(x: &X) { + | -- help: consider further restricting this bound: `Y: std::marker::Sized +` +... LL | let y: Y; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `Y` = note: to learn more, visit - = help: consider adding a `where Y: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:7:12 | +LL | fn f1(x: &X) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` +LL | let _: W; // <-- this is OK, no bindings created, no initializer. LL | let _: (isize, (X, isize)); | ^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: only the last element of a tuple may have a dynamically sized type error[E0277]: the size for values of type `Z` cannot be known at compilation time --> $DIR/unsized6.rs:11:12 | +LL | fn f1(x: &X) { + | -- help: consider further restricting this bound: `Z: std::marker::Sized +` +... LL | let y: (isize, (Z, usize)); | ^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `Z` = note: to learn more, visit - = help: consider adding a `where Z: std::marker::Sized` bound = note: only the last element of a tuple may have a dynamically sized type error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:15:9 | +LL | fn f2(x: &X) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | let y: X; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `Y` cannot be known at compilation time --> $DIR/unsized6.rs:17:12 | +LL | fn f2(x: &X) { + | -- help: consider further restricting this bound: `Y: std::marker::Sized +` +... LL | let y: (isize, (Y, isize)); | ^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `Y` = note: to learn more, visit - = help: consider adding a `where Y: std::marker::Sized` bound = note: only the last element of a tuple may have a dynamically sized type error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:22:9 | +LL | fn f3(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | let y: X = *x1; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:24:9 | +LL | fn f3(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` +... LL | let y = *x2; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:26:10 | +LL | fn f3(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` +... LL | let (y, z) = (*x3, 4); | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:30:9 | +LL | fn f4(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` LL | let y: X = *x1; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:32:9 | +LL | fn f4(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` +... LL | let y = *x2; | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature error[E0277]: the size for values of type `X` cannot be known at compilation time --> $DIR/unsized6.rs:34:10 | +LL | fn f4(x1: Box, x2: Box, x3: Box) { + | -- help: consider further restricting this bound: `X: std::marker::Sized +` +... LL | let (y, z) = (*x3, 4); | ^ doesn't have a size known at compile-time | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature @@ -131,11 +150,12 @@ error[E0277]: the size for values of type `X` cannot be known at compilation tim --> $DIR/unsized6.rs:38:18 | LL | fn g1(x: X) {} - | ^ doesn't have a size known at compile-time + | -- ^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `X: std::marker::Sized +` | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature @@ -143,11 +163,12 @@ error[E0277]: the size for values of type `X` cannot be known at compilation tim --> $DIR/unsized6.rs:40:22 | LL | fn g2(x: X) {} - | ^ doesn't have a size known at compile-time + | -- ^ doesn't have a size known at compile-time + | | + | help: consider further restricting this bound: `X: std::marker::Sized +` | = help: the trait `std::marker::Sized` is not implemented for `X` = note: to learn more, visit - = help: consider adding a `where X: std::marker::Sized` bound = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature diff --git a/src/test/ui/wf/wf-impl-associated-type-trait.stderr b/src/test/ui/wf/wf-impl-associated-type-trait.stderr index ceafb4f6157..6d71670e6a8 100644 --- a/src/test/ui/wf/wf-impl-associated-type-trait.stderr +++ b/src/test/ui/wf/wf-impl-associated-type-trait.stderr @@ -4,10 +4,10 @@ error[E0277]: the trait bound `T: MyHash` is not satisfied LL | pub struct MySet { | -------------------------- required by `MySet` ... +LL | impl Foo for T { + | - help: consider restricting this bound: `T: MyHash` LL | type Bar = MySet; | ^^^^^^^^^^^^^^^^^^^^ the trait `MyHash` is not implemented for `T` - | - = help: consider adding a `where T: MyHash` bound error: aborting due to previous error diff --git a/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr b/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr index 1e258864d03..21f825ac9ef 100644 --- a/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr +++ b/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr @@ -4,11 +4,11 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied LL | trait ExtraCopy { } | ----------------------- required by `ExtraCopy` ... +LL | impl Foo { + | - help: consider restricting this bound: `U: std::marker::Copy` LL | / fn foo(self) where T: ExtraCopy LL | | {} | |______^ the trait `std::marker::Copy` is not implemented for `U` - | - = help: consider adding a `where U: std::marker::Copy` bound error: aborting due to previous error