From 3075f0351386d8fc4110b6c5d7ee618f888d824d Mon Sep 17 00:00:00 2001 From: Camille GILLOT Date: Tue, 25 Oct 2022 16:10:19 +0000 Subject: [PATCH] Resolve lifetimes using the regular logic for RPIT. --- .../src/collect/lifetimes.rs | 73 +++++++++---------- src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs | 3 + .../ui/impl-trait/impl-fn-hrtb-bounds.stderr | 39 ++++++++-- .../impl-trait/impl-fn-parsing-ambiguities.rs | 3 +- .../impl-fn-parsing-ambiguities.stderr | 13 +++- src/test/ui/impl-trait/issues/issue-67830.rs | 2 + .../ui/impl-trait/issues/issue-67830.stderr | 20 ++++- .../ui/impl-trait/issues/issue-88236-2.rs | 5 ++ .../ui/impl-trait/issues/issue-88236-2.stderr | 60 ++++++++++++++- src/test/ui/impl-trait/nested-rpit-hrtb.rs | 18 +++-- .../ui/impl-trait/nested-rpit-hrtb.stderr | 64 ++++++++++++++-- 11 files changed, 238 insertions(+), 62 deletions(-) diff --git a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs index 1fec8f027bd..895f32114dc 100644 --- a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs +++ b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs @@ -452,7 +452,9 @@ fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) { intravisit::walk_item(this, item) }); } - hir::ItemKind::OpaqueTy(hir::OpaqueTy { .. }) => { + hir::ItemKind::OpaqueTy(hir::OpaqueTy { + origin: hir::OpaqueTyOrigin::TyAlias, .. + }) => { // Opaque types are visited when we visit the // `TyKind::OpaqueDef`, so that they have the lifetimes from // their parent opaque_ty in scope. @@ -478,6 +480,37 @@ fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) { }); } } + hir::ItemKind::OpaqueTy(hir::OpaqueTy { + origin: hir::OpaqueTyOrigin::FnReturn(_) | hir::OpaqueTyOrigin::AsyncFn(_), + generics, + .. + }) => { + // We want to start our early-bound indices at the end of the parent scope, + // not including any parent `impl Trait`s. + let mut lifetimes = FxIndexMap::default(); + debug!(?generics.params); + for param in generics.params { + match param.kind { + GenericParamKind::Lifetime { .. } => { + let (def_id, reg) = Region::early(self.tcx.hir(), ¶m); + lifetimes.insert(def_id, reg); + } + GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {} + } + } + + let scope = Scope::Binder { + hir_id: item.hir_id(), + lifetimes, + s: self.scope, + scope_type: BinderScopeType::Normal, + where_bound_origin: None, + }; + self.with(scope, |this| { + let scope = Scope::TraitRefBoundary { s: this.scope }; + this.with(scope, |this| intravisit::walk_item(this, item)) + }); + } hir::ItemKind::TyAlias(_, ref generics) | hir::ItemKind::Enum(_, ref generics) | hir::ItemKind::Struct(_, ref generics) @@ -604,7 +637,7 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) { // ^ ^ this gets resolved in the scope of // the opaque_ty generics let opaque_ty = self.tcx.hir().item(item_id); - let (generics, bounds) = match opaque_ty.kind { + match opaque_ty.kind { hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin: hir::OpaqueTyOrigin::TyAlias, .. @@ -625,10 +658,8 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) { } hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin: hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..), - ref generics, - bounds, .. - }) => (generics, bounds), + }) => {} ref i => bug!("`impl Trait` pointed to non-opaque type?? {:#?}", i), }; @@ -681,38 +712,6 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) { self.uninsert_lifetime_on_error(lifetime, def.unwrap()); } } - - // We want to start our early-bound indices at the end of the parent scope, - // not including any parent `impl Trait`s. - let mut lifetimes = FxIndexMap::default(); - debug!(?generics.params); - for param in generics.params { - match param.kind { - GenericParamKind::Lifetime { .. } => { - let (def_id, reg) = Region::early(self.tcx.hir(), ¶m); - lifetimes.insert(def_id, reg); - } - GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {} - } - } - self.record_late_bound_vars(ty.hir_id, vec![]); - - let scope = Scope::Binder { - hir_id: ty.hir_id, - lifetimes, - s: self.scope, - scope_type: BinderScopeType::Normal, - where_bound_origin: None, - }; - self.with(scope, |this| { - let scope = Scope::TraitRefBoundary { s: this.scope }; - this.with(scope, |this| { - this.visit_generics(generics); - for bound in bounds { - this.visit_param_bound(bound); - } - }) - }); } _ => intravisit::walk_ty(self, ty), } diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs index 527a4586fd7..06c3d9ad434 100644 --- a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs +++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs @@ -4,16 +4,19 @@ fn a() -> impl Fn(&u8) -> (impl Debug + '_) { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet |x| x + //~^ ERROR lifetime may not live long enough } fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet |x| x + //~^ ERROR lifetime may not live long enough } fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet |x| x + //~^ ERROR lifetime may not live long enough } fn d() -> impl Fn() -> (impl Debug + '_) { diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr index 443ffeb55cd..b6857a6c4c5 100644 --- a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr +++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr @@ -1,5 +1,5 @@ error[E0106]: missing lifetime specifier - --> $DIR/impl-fn-hrtb-bounds.rs:19:38 + --> $DIR/impl-fn-hrtb-bounds.rs:22:38 | LL | fn d() -> impl Fn() -> (impl Debug + '_) { | ^^ expected named lifetime parameter @@ -22,30 +22,57 @@ note: lifetime declared here LL | fn a() -> impl Fn(&u8) -> (impl Debug + '_) { | ^ +error: lifetime may not live long enough + --> $DIR/impl-fn-hrtb-bounds.rs:6:9 + | +LL | |x| x + | -- ^ returning this value requires that `'1` must outlive `'2` + | || + | |return type of closure is impl Debug + '2 + | has type `&'1 u8` + error: higher kinded lifetime bounds on nested opaque types are not supported yet - --> $DIR/impl-fn-hrtb-bounds.rs:9:52 + --> $DIR/impl-fn-hrtb-bounds.rs:10:52 | LL | fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) { | ^^ | note: lifetime declared here - --> $DIR/impl-fn-hrtb-bounds.rs:9:20 + --> $DIR/impl-fn-hrtb-bounds.rs:10:20 | LL | fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) { | ^^ +error: lifetime may not live long enough + --> $DIR/impl-fn-hrtb-bounds.rs:12:9 + | +LL | |x| x + | -- ^ returning this value requires that `'1` must outlive `'2` + | || + | |return type of closure is impl Debug + '2 + | has type `&'1 u8` + error: higher kinded lifetime bounds on nested opaque types are not supported yet - --> $DIR/impl-fn-hrtb-bounds.rs:14:52 + --> $DIR/impl-fn-hrtb-bounds.rs:16:52 | LL | fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) { | ^^ | note: lifetime declared here - --> $DIR/impl-fn-hrtb-bounds.rs:14:20 + --> $DIR/impl-fn-hrtb-bounds.rs:16:20 | LL | fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) { | ^^ -error: aborting due to 4 previous errors +error: lifetime may not live long enough + --> $DIR/impl-fn-hrtb-bounds.rs:18:9 + | +LL | |x| x + | -- ^ returning this value requires that `'1` must outlive `'2` + | || + | |return type of closure is impl Debug + '2 + | has type `&'1 u8` + +error: aborting due to 7 previous errors For more information about this error, try `rustc --explain E0106`. diff --git a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs index 3e760710797..a4a1f1dcee1 100644 --- a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs +++ b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs @@ -3,8 +3,9 @@ fn a() -> impl Fn(&u8) -> impl Debug + '_ { //~^ ERROR ambiguous `+` in a type - //~^^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet + //~| ERROR higher kinded lifetime bounds on nested opaque types are not supported yet |x| x + //~^ ERROR lifetime may not live long enough } fn b() -> impl Fn() -> impl Debug + Send { diff --git a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr index cf6e5ef7bac..e18e89700b4 100644 --- a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr +++ b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr @@ -5,7 +5,7 @@ LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ { | ^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + '_)` error: ambiguous `+` in a type - --> $DIR/impl-fn-parsing-ambiguities.rs:10:24 + --> $DIR/impl-fn-parsing-ambiguities.rs:11:24 | LL | fn b() -> impl Fn() -> impl Debug + Send { | ^^^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + Send)` @@ -22,5 +22,14 @@ note: lifetime declared here LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ { | ^ -error: aborting due to 3 previous errors +error: lifetime may not live long enough + --> $DIR/impl-fn-parsing-ambiguities.rs:7:9 + | +LL | |x| x + | -- ^ returning this value requires that `'1` must outlive `'2` + | || + | |return type of closure is impl Debug + '2 + | has type `&'1 u8` + +error: aborting due to 4 previous errors diff --git a/src/test/ui/impl-trait/issues/issue-67830.rs b/src/test/ui/impl-trait/issues/issue-67830.rs index 92f7e005dbf..6dc8935c777 100644 --- a/src/test/ui/impl-trait/issues/issue-67830.rs +++ b/src/test/ui/impl-trait/issues/issue-67830.rs @@ -21,6 +21,8 @@ fn call(&self, arg: A) -> Self::Output { fn test() -> impl for<'a> MyFn<&'a A, Output=impl Iterator + 'a> { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet Wrap(|a| Some(a).into_iter()) + //~^ ERROR implementation of `FnOnce` is not general enough + //~| ERROR implementation of `FnOnce` is not general enough } fn main() {} diff --git a/src/test/ui/impl-trait/issues/issue-67830.stderr b/src/test/ui/impl-trait/issues/issue-67830.stderr index d3ea8cb0377..cbc7cd54201 100644 --- a/src/test/ui/impl-trait/issues/issue-67830.stderr +++ b/src/test/ui/impl-trait/issues/issue-67830.stderr @@ -10,5 +10,23 @@ note: lifetime declared here LL | fn test() -> impl for<'a> MyFn<&'a A, Output=impl Iterator + 'a> { | ^^ -error: aborting due to previous error +error: implementation of `FnOnce` is not general enough + --> $DIR/issue-67830.rs:23:5 + | +LL | Wrap(|a| Some(a).into_iter()) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `FnOnce` is not general enough + | + = note: closure with signature `fn(&'2 A) -> std::option::IntoIter<&A>` must implement `FnOnce<(&'1 A,)>`, for any lifetime `'1`... + = note: ...but it actually implements `FnOnce<(&'2 A,)>`, for some specific lifetime `'2` + +error: implementation of `FnOnce` is not general enough + --> $DIR/issue-67830.rs:23:5 + | +LL | Wrap(|a| Some(a).into_iter()) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `FnOnce` is not general enough + | + = note: closure with signature `fn(&'2 A) -> std::option::IntoIter<&A>` must implement `FnOnce<(&'1 A,)>`, for any lifetime `'1`... + = note: ...but it actually implements `FnOnce<(&'2 A,)>`, for some specific lifetime `'2` + +error: aborting due to 3 previous errors diff --git a/src/test/ui/impl-trait/issues/issue-88236-2.rs b/src/test/ui/impl-trait/issues/issue-88236-2.rs index fde8a6704cc..f4354d1b2ae 100644 --- a/src/test/ui/impl-trait/issues/issue-88236-2.rs +++ b/src/test/ui/impl-trait/issues/issue-88236-2.rs @@ -18,11 +18,16 @@ fn make_impl() -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> {} fn make_weird_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet &() + //~^ ERROR implementation of `Hrtb` is not general enough + //~| ERROR implementation of `Hrtb` is not general enough } fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet x + //~^ ERROR implementation of `Hrtb` is not general enough + //~| ERROR implementation of `Hrtb` is not general enough + //~| ERROR lifetime may not live long enough } fn main() {} diff --git a/src/test/ui/impl-trait/issues/issue-88236-2.stderr b/src/test/ui/impl-trait/issues/issue-88236-2.stderr index 8605d07abe9..99c91d16a64 100644 --- a/src/test/ui/impl-trait/issues/issue-88236-2.stderr +++ b/src/test/ui/impl-trait/issues/issue-88236-2.stderr @@ -22,17 +22,71 @@ note: lifetime declared here LL | fn make_weird_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { | ^^ +error: implementation of `Hrtb` is not general enough + --> $DIR/issue-88236-2.rs:20:5 + | +LL | &() + | ^^^ implementation of `Hrtb` is not general enough + | + = note: `Hrtb<'0>` would have to be implemented for the type `&()`, for any lifetime `'0`... + = note: ...but `Hrtb<'1>` is actually implemented for the type `&'1 ()`, for some specific lifetime `'1` + +error: implementation of `Hrtb` is not general enough + --> $DIR/issue-88236-2.rs:20:5 + | +LL | &() + | ^^^ implementation of `Hrtb` is not general enough + | + = note: `Hrtb<'0>` would have to be implemented for the type `&()`, for any lifetime `'0`... + = note: ...but `Hrtb<'1>` is actually implemented for the type `&'1 ()`, for some specific lifetime `'1` + error: higher kinded lifetime bounds on nested opaque types are not supported yet - --> $DIR/issue-88236-2.rs:23:78 + --> $DIR/issue-88236-2.rs:25:78 | LL | fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { | ^^ | note: lifetime declared here - --> $DIR/issue-88236-2.rs:23:45 + --> $DIR/issue-88236-2.rs:25:45 | LL | fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { | ^^ -error: aborting due to 3 previous errors +error: lifetime may not live long enough + --> $DIR/issue-88236-2.rs:27:5 + | +LL | fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> { + | -- lifetime `'b` defined here +LL | +LL | x + | ^ returning this value requires that `'b` must outlive `'static` + | +help: to declare that `impl for<'a> Hrtb<'a, Assoc = impl Send + 'static>` captures data from argument `x`, you can add an explicit `'b` lifetime bound + | +LL | fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a> + 'b { + | ++++ +help: to declare that `impl Send + 'a` captures data from argument `x`, you can add an explicit `'b` lifetime bound + | +LL | fn make_bad_impl<'b>(x: &'b ()) -> impl for<'a> Hrtb<'a, Assoc = impl Send + 'a + 'b> { + | ++++ + +error: implementation of `Hrtb` is not general enough + --> $DIR/issue-88236-2.rs:27:5 + | +LL | x + | ^ implementation of `Hrtb` is not general enough + | + = note: `Hrtb<'0>` would have to be implemented for the type `&()`, for any lifetime `'0`... + = note: ...but `Hrtb<'1>` is actually implemented for the type `&'1 ()`, for some specific lifetime `'1` + +error: implementation of `Hrtb` is not general enough + --> $DIR/issue-88236-2.rs:27:5 + | +LL | x + | ^ implementation of `Hrtb` is not general enough + | + = note: `Hrtb<'0>` would have to be implemented for the type `&()`, for any lifetime `'0`... + = note: ...but `Hrtb<'1>` is actually implemented for the type `&'1 ()`, for some specific lifetime `'1` + +error: aborting due to 8 previous errors diff --git a/src/test/ui/impl-trait/nested-rpit-hrtb.rs b/src/test/ui/impl-trait/nested-rpit-hrtb.rs index abf6a7e956c..377658b95c9 100644 --- a/src/test/ui/impl-trait/nested-rpit-hrtb.rs +++ b/src/test/ui/impl-trait/nested-rpit-hrtb.rs @@ -31,34 +31,40 @@ fn one_hrtb_trait_param() -> impl for<'a> Foo<'a, Assoc = impl Qux<'a>> {} fn one_hrtb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'a> {} //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet +//~| ERROR implementation of `Bar` is not general enough fn one_hrtb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl Qux<'a>> {} //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet +//~| ERROR the trait bound `&(): Qux<'static>` is not satisfied -// This should pass. +// This should resolve. fn one_hrtb_mention_fn_trait_param<'b>() -> impl for<'a> Foo<'a, Assoc = impl Qux<'b>> {} -// This should pass. +// This should resolve. fn one_hrtb_mention_fn_outlives<'b>() -> impl for<'a> Foo<'a, Assoc = impl Sized + 'b> {} -// This should pass. +// This should resolve. fn one_hrtb_mention_fn_trait_param_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Qux<'b>> {} +//~^ ERROR the trait bound `&(): Qux<'b>` is not satisfied -// This should pass. +// This should resolve. fn one_hrtb_mention_fn_outlives_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'b> {} +//~^ ERROR implementation of `Bar` is not general enough -// This should pass. +// This should resolve. fn two_htrb_trait_param() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Qux<'b>> {} // `'b` is not in scope for the outlives bound. fn two_htrb_outlives() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Sized + 'b> {} //~^ ERROR use of undeclared lifetime name `'b` [E0261] -// This should pass. +// This should resolve. fn two_htrb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Qux<'b>> {} +//~^ ERROR the trait bound `for<'b> &(): Qux<'b>` is not satisfied // `'b` is not in scope for the outlives bound. fn two_htrb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Sized + 'b> {} //~^ ERROR use of undeclared lifetime name `'b` [E0261] +//~| ERROR implementation of `Bar` is not general enough fn main() {} diff --git a/src/test/ui/impl-trait/nested-rpit-hrtb.stderr b/src/test/ui/impl-trait/nested-rpit-hrtb.stderr index 3dbe6ebadfb..fb2a7445357 100644 --- a/src/test/ui/impl-trait/nested-rpit-hrtb.stderr +++ b/src/test/ui/impl-trait/nested-rpit-hrtb.stderr @@ -1,5 +1,5 @@ error[E0261]: use of undeclared lifetime name `'b` - --> $DIR/nested-rpit-hrtb.rs:54:77 + --> $DIR/nested-rpit-hrtb.rs:58:77 | LL | fn two_htrb_outlives() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Sized + 'b> {} | ^^ undeclared lifetime @@ -15,7 +15,7 @@ LL | fn two_htrb_outlives<'b>() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Siz | ++++ error[E0261]: use of undeclared lifetime name `'b` - --> $DIR/nested-rpit-hrtb.rs:61:82 + --> $DIR/nested-rpit-hrtb.rs:66:82 | LL | fn two_htrb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Sized + 'b> {} | ^^ undeclared lifetime @@ -65,18 +65,70 @@ note: lifetime declared here LL | fn one_hrtb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'a> {} | ^^ +error: implementation of `Bar` is not general enough + --> $DIR/nested-rpit-hrtb.rs:32:78 + | +LL | fn one_hrtb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'a> {} + | ^^ implementation of `Bar` is not general enough + | + = note: `()` must implement `Bar<'0>`, for any lifetime `'0`... + = note: ...but it actually implements `Bar<'1>`, for some specific lifetime `'1` + error: higher kinded lifetime bounds on nested opaque types are not supported yet - --> $DIR/nested-rpit-hrtb.rs:35:73 + --> $DIR/nested-rpit-hrtb.rs:36:73 | LL | fn one_hrtb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl Qux<'a>> {} | ^^ | note: lifetime declared here - --> $DIR/nested-rpit-hrtb.rs:35:44 + --> $DIR/nested-rpit-hrtb.rs:36:44 | LL | fn one_hrtb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl Qux<'a>> {} | ^^ -error: aborting due to 6 previous errors +error[E0277]: the trait bound `&(): Qux<'static>` is not satisfied + --> $DIR/nested-rpit-hrtb.rs:36:64 + | +LL | fn one_hrtb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl Qux<'a>> {} + | ^^^^^^^^^^^^ the trait `Qux<'static>` is not implemented for `&()` + | + = help: the trait `Qux<'_>` is implemented for `()` + +error[E0277]: the trait bound `&(): Qux<'b>` is not satisfied + --> $DIR/nested-rpit-hrtb.rs:47:79 + | +LL | fn one_hrtb_mention_fn_trait_param_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Qux<'b>> {} + | ^^^^^^^^^^^^ the trait `Qux<'b>` is not implemented for `&()` + | + = help: the trait `Qux<'_>` is implemented for `()` + +error: implementation of `Bar` is not general enough + --> $DIR/nested-rpit-hrtb.rs:51:93 + | +LL | fn one_hrtb_mention_fn_outlives_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'b> {} + | ^^ implementation of `Bar` is not general enough + | + = note: `()` must implement `Bar<'0>`, for any lifetime `'0`... + = note: ...but it actually implements `Bar<'1>`, for some specific lifetime `'1` + +error[E0277]: the trait bound `for<'b> &(): Qux<'b>` is not satisfied + --> $DIR/nested-rpit-hrtb.rs:62:64 + | +LL | fn two_htrb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Qux<'b>> {} + | ^^^^^^^^^^^^^^^^^^^^ the trait `for<'b> Qux<'b>` is not implemented for `&()` + | + = help: the trait `Qux<'_>` is implemented for `()` + +error: implementation of `Bar` is not general enough + --> $DIR/nested-rpit-hrtb.rs:66:86 + | +LL | fn two_htrb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Sized + 'b> {} + | ^^ implementation of `Bar` is not general enough + | + = note: `()` must implement `Bar<'0>`, for any lifetime `'0`... + = note: ...but it actually implements `Bar<'1>`, for some specific lifetime `'1` + +error: aborting due to 12 previous errors -For more information about this error, try `rustc --explain E0261`. +Some errors have detailed explanations: E0261, E0277. +For more information about an error, try `rustc --explain E0261`. -- 2.44.0