Point at impl assoc type on projection error

estebank · estebank · commit 280d4e1c37da · 2021-06-10T20:00:46.000-07:00
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -1262,6 +1262,38 @@ impl<'a, 'tcx> InferCtxtPrivExt<'tcx> for InferCtxt<'a, 'tcx> {
                 );
                 self.note_type_err(&mut diag, &obligation.cause, None, values, err);
                 self.note_obligation_cause(&mut diag, obligation);
+                match predicate.kind().skip_binder() {
+                    ty::PredicateKind::Projection(proj) => {
+                        let item = self
+                            .tcx
+                            .opt_associated_item(proj.projection_ty.item_def_id)
+                            .and_then(|trait_assoc_item| {
+                                self.tcx
+                                    .trait_of_item(proj.projection_ty.item_def_id)
+                                    .map(|id| (trait_assoc_item, id))
+                            })
+                            .and_then(|(trait_assoc_item, id)| {
+                                self.tcx.find_map_relevant_impl(
+                                    id,
+                                    proj.projection_ty.self_ty(),
+                                    |did| {
+                                        self.tcx
+                                            .associated_items(did)
+                                            .in_definition_order()
+                                            .filter(|assoc| assoc.ident == trait_assoc_item.ident)
+                                            .next()
+                                    },
+                                )
+                            });
+                        if let Some(item) = item {
+                            diag.span_label(
+                                item.ident.span,
+                                &format!("type mismatch with `{}` here", proj.ty),
+                            );
+                        }
+                    }
+                    _ => {}
+                }
                 diag.emit();
             }
         });
diff --git a/src/test/ui/associated-types/associated-types-binding-to-type-defined-in-supertrait.stderr b/src/test/ui/associated-types/associated-types-binding-to-type-defined-in-supertrait.stderr
@@ -1,6 +1,9 @@
 error[E0271]: type mismatch resolving `<ModelT as Vehicle>::Color == Blue`
   --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:31:10
    |
+LL | impl Vehicle for ModelT { type Color = Black; }
+   |                                ----- type mismatch with `Blue` here
+...
 LL | fn blue_car<C:Car<Color=Blue>>(c: C) {
    |                   ---------- required by this bound in `blue_car`
 ...
@@ -10,6 +13,9 @@ LL | fn b() { blue_car(ModelT); }
 error[E0271]: type mismatch resolving `<ModelU as Vehicle>::Color == Black`
   --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:32:10
    |
+LL | impl Vehicle for ModelU { type Color = Blue; }
+   |                                ----- type mismatch with `Black` here
+...
 LL | fn black_car<C:Car<Color=Black>>(c: C) {
    |                    ----------- required by this bound in `black_car`
 ...
diff --git a/src/test/ui/associated-types/associated-types-eq-3.stderr b/src/test/ui/associated-types/associated-types-eq-3.stderr
@@ -16,6 +16,9 @@ LL | fn foo2<I: Foo<A = Bar>>(x: I) {
 error[E0271]: type mismatch resolving `<isize as Foo>::A == Bar`
   --> $DIR/associated-types-eq-3.rs:38:5
    |
+LL |     type A = usize;
+   |          - type mismatch with `Bar` here
+...
 LL | fn foo1<I: Foo<A=Bar>>(x: I) {
    |                ----- required by this bound in `foo1`
 ...
@@ -25,6 +28,9 @@ LL |     foo1(a);
 error[E0271]: type mismatch resolving `<isize as Foo>::A == Bar`
   --> $DIR/associated-types-eq-3.rs:41:9
    |
+LL |     type A = usize;
+   |          - type mismatch with `Bar` here
+...
 LL |     baz(&a);
    |         ^^ expected struct `Bar`, found `usize`
    |
diff --git a/src/test/ui/associated-types/associated-types-eq-hr.stderr b/src/test/ui/associated-types/associated-types-eq-hr.stderr
@@ -1,6 +1,9 @@
 error[E0271]: type mismatch resolving `for<'x> <UintStruct as TheTrait<&'x isize>>::A == &'x isize`
   --> $DIR/associated-types-eq-hr.rs:87:5
    |
+LL |     type A = &'a usize;
+   |          - type mismatch with `&'x isize` here
+...
 LL | fn foo<T>()
    |    --- required by a bound in this
 LL | where
@@ -16,6 +19,9 @@ LL |     foo::<UintStruct>();
 error[E0271]: type mismatch resolving `for<'x> <IntStruct as TheTrait<&'x isize>>::A == &'x usize`
   --> $DIR/associated-types-eq-hr.rs:91:5
    |
+LL |     type A = &'a isize;
+   |          - type mismatch with `&'x usize` here
+...
 LL | fn bar<T>()
    |    --- required by a bound in this
 LL | where
diff --git a/src/test/ui/associated-types/associated-types-issue-20346.stderr b/src/test/ui/associated-types/associated-types-issue-20346.stderr
@@ -4,6 +4,9 @@ error[E0271]: type mismatch resolving `<Adapter<I> as Iterator>::Item == Option<
 LL | fn is_iterator_of<A, I: Iterator<Item=A>>(_: &I) {}
    |                                  ------ required by this bound in `is_iterator_of`
 ...
+LL |     type Item = T;
+   |          ---- type mismatch with `Option<T>` here
+...
 LL | fn test_adapter<T, I: Iterator<Item=Option<T>>>(it: I) {
    |                 - this type parameter
 ...
diff --git a/src/test/ui/associated-types/associated-types-overridden-binding-2.stderr b/src/test/ui/associated-types/associated-types-overridden-binding-2.stderr
@@ -3,6 +3,11 @@ error[E0271]: type mismatch resolving `<std::vec::IntoIter<u32> as Iterator>::It
    |
 LL |     let _: &dyn I32Iterator<Item = u32> = &vec![42].into_iter();
    |                                           ^^^^^^^^^^^^^^^^^^^^^ expected `i32`, found `u32`
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `i32` here
    |
    = note: required for the cast to the object type `dyn Iterator<Item = u32, Item = i32>`
 
diff --git a/src/test/ui/associated-types/issue-44153.stderr b/src/test/ui/associated-types/issue-44153.stderr
@@ -4,6 +4,9 @@ error[E0271]: type mismatch resolving `<() as Array>::Element == &()`
 LL |     fn visit() {}
    |     ---------- required by `Visit::visit`
 ...
+LL |     type Element = ();
+   |          ------- type mismatch with `&()` here
+...
 LL |     <() as Visit>::visit();
    |     ^^^^^^^^^^^^^^^^^^^^ expected `&()`, found `()`
    |
diff --git a/src/test/ui/associated-types/issue-72806.stderr b/src/test/ui/associated-types/issue-72806.stderr
@@ -6,6 +6,9 @@ LL |     type Sibling: Bar2<Ok=char>;
 ...
 LL |     type Sibling = Foo2;
    |                    ^^^^ expected `char`, found `u32`
+...
+LL |     type Ok = u32;
+   |          -- type mismatch with `char` here
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/associated-types/point-at-type-on-obligation-failure.stderr b/src/test/ui/associated-types/point-at-type-on-obligation-failure.stderr
@@ -6,6 +6,9 @@ LL |     type Sibling: Bar2<Ok=Self::Ok>;
 ...
 LL |     type Sibling = Foo2;
    |                    ^^^^ expected `()`, found `u32`
+...
+LL |     type Ok = u32;
+   |          -- type mismatch with `()` here
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/async-await/async-block-control-flow-static-semantics.stderr b/src/test/ui/async-await/async-block-control-flow-static-semantics.stderr
@@ -36,6 +36,11 @@ error[E0271]: type mismatch resolving `<impl Future as Future>::Output == ()`
    |
 LL |     let _: &dyn Future<Output = ()> = &block;
    |                                       ^^^^^^ expected `()`, found `u8`
+   | 
+  ::: $SRC_DIR/core/src/future/future.rs:LL:COL
+   |
+LL |     type Output = F::Output;
+   |          ------ type mismatch with `()` here
    |
    = note: required for the cast to the object type `dyn Future<Output = ()>`
 
@@ -52,6 +57,11 @@ error[E0271]: type mismatch resolving `<impl Future as Future>::Output == ()`
    |
 LL |     let _: &dyn Future<Output = ()> = &block;
    |                                       ^^^^^^ expected `()`, found `u8`
+   | 
+  ::: $SRC_DIR/core/src/future/future.rs:LL:COL
+   |
+LL |     type Output = F::Output;
+   |          ------ type mismatch with `()` here
    |
    = note: required for the cast to the object type `dyn Future<Output = ()>`
 
diff --git a/src/test/ui/error-codes/E0271.stderr b/src/test/ui/error-codes/E0271.stderr
@@ -4,6 +4,9 @@ error[E0271]: type mismatch resolving `<i8 as Trait>::AssociatedType == u32`
 LL | fn foo<T>(t: T) where T: Trait<AssociatedType=u32> {
    |                                ------------------ required by this bound in `foo`
 ...
+LL | impl Trait for i8 { type AssociatedType = &'static str; }
+   |                          -------------- type mismatch with `u32` here
+...
 LL |     foo(3_i8);
    |     ^^^ expected `u32`, found `&str`
 
diff --git a/src/test/ui/generator/generator-yielding-or-returning-itself.stderr b/src/test/ui/generator/generator-yielding-or-returning-itself.stderr
@@ -8,6 +8,11 @@ LL |     where T: Generator<Yield = (), Return = T>
 ...
 LL |     want_cyclic_generator_return(|| {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cyclic type of infinite size
+   | 
+  ::: $SRC_DIR/core/src/ops/generator.rs:LL:COL
+   |
+LL |     type Return = G::Return;
+   |          ------ type mismatch with `[generator@$DIR/generator-yielding-or-returning-itself.rs:15:34: 19:6]` here
    |
    = note: closures cannot capture themselves or take themselves as argument;
            this error may be the result of a recent compiler bug-fix,
@@ -24,6 +29,11 @@ LL |     where T: Generator<Yield = T, Return = ()>
 ...
 LL |     want_cyclic_generator_yield(|| {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ cyclic type of infinite size
+   | 
+  ::: $SRC_DIR/core/src/ops/generator.rs:LL:COL
+   |
+LL |     type Yield = G::Yield;
+   |          ----- type mismatch with `[generator@$DIR/generator-yielding-or-returning-itself.rs:28:33: 32:6]` here
    |
    = note: closures cannot capture themselves or take themselves as argument;
            this error may be the result of a recent compiler bug-fix,
diff --git a/src/test/ui/generator/type-mismatch-signature-deduction.stderr b/src/test/ui/generator/type-mismatch-signature-deduction.stderr
@@ -17,6 +17,11 @@ error[E0271]: type mismatch resolving `<[generator@$DIR/type-mismatch-signature-
    |
 LL | fn foo() -> impl Generator<Return = i32> {
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `i32`, found enum `Result`
+   | 
+  ::: $SRC_DIR/core/src/ops/generator.rs:LL:COL
+   |
+LL |     type Return = G::Return;
+   |          ------ type mismatch with `i32` here
    |
    = note: expected type `i32`
               found enum `Result<{integer}, _>`
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
@@ -17,6 +17,11 @@ LL | impl<T: Copy + std::ops::Deref> UnsafeCopy<T> for T {
    |      - this type parameter
 LL |     type Item<'a> = T;
    |                     ^ expected type parameter `T`, found associated type
+   | 
+  ::: $SRC_DIR/core/src/ops/deref.rs:LL:COL
+   |
+LL |     type Target = T;
+   |          ------ type mismatch with `T` here
    |
    = note: expected type parameter `T`
              found associated type `<T as Deref>::Target`
diff --git a/src/test/ui/generic-associated-types/issue-74684-2.stderr b/src/test/ui/generic-associated-types/issue-74684-2.stderr
@@ -10,6 +10,9 @@ LL | #![feature(generic_associated_types)]
 error[E0271]: type mismatch resolving `<{integer} as Fun>::F<'_> == [u8]`
   --> $DIR/issue-74684-2.rs:24:5
    |
+LL |     type F<'a> = i32;
+   |          - type mismatch with `[u8]` here
+...
 LL | fn bug<'a, T: ?Sized + Fun<F<'a> = [u8]>>(t: Box<T>) -> &'static T::F<'a> {
    |                            ------------ required by this bound in `bug`
 ...
diff --git a/src/test/ui/hrtb/issue-62203-hrtb-ice.stderr b/src/test/ui/hrtb/issue-62203-hrtb-ice.stderr
@@ -1,6 +1,9 @@
 error[E0271]: type mismatch resolving `for<'r> <L<[closure@$DIR/issue-62203-hrtb-ice.rs:42:17: 42:39]> as T0<'r, (<Unit2 as Ty<'r>>::V,)>>::O == <_ as Ty<'r>>::V`
   --> $DIR/issue-62203-hrtb-ice.rs:38:19
    |
+LL |     type O = T::Output;
+   |          - type mismatch with `<_ as Ty<'r>>::V` here
+...
 LL |     let v = Unit2.m(
    |                   ^ expected struct `Unit4`, found associated type
    |
@@ -14,6 +17,11 @@ error[E0271]: type mismatch resolving `<[closure@$DIR/issue-62203-hrtb-ice.rs:42
    |
 LL |     let v = Unit2.m(
    |                   ^ expected struct `Unit4`, found struct `Unit3`
+   | 
+  ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL |         type Output = F::Output;
+   |              ------ type mismatch with `Unit3` here
    |
 note: required because of the requirements on the impl of `for<'r> T0<'r, (<Unit2 as Ty<'r>>::V,)>` for `L<[closure@$DIR/issue-62203-hrtb-ice.rs:42:17: 42:39]>`
   --> $DIR/issue-62203-hrtb-ice.rs:17:16
diff --git a/src/test/ui/impl-trait/bound-normalization-fail.stderr b/src/test/ui/impl-trait/bound-normalization-fail.stderr
@@ -10,6 +10,9 @@ LL | #![feature(impl_trait_in_bindings)]
 error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as impl_trait::Trait>::Assoc`
   --> $DIR/bound-normalization-fail.rs:26:32
    |
+LL |     type Output = T;
+   |          ------ type mismatch with `<T as impl_trait::Trait>::Assoc` here
+...
 LL |     fn foo_fail<T: Trait>() -> impl FooLike<Output=T::Assoc> {
    |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected associated type, found `()`
    |
@@ -29,6 +32,9 @@ LL |     fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output=T::Assoc> {
 error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as lifetimes::Trait<'static>>::Assoc`
   --> $DIR/bound-normalization-fail.rs:42:41
    |
+LL |     type Output = T;
+   |          ------ type mismatch with `<T as lifetimes::Trait<'static>>::Assoc` here
+...
 LL |     fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output=T::Assoc> {
    |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected associated type, found `()`
    |
diff --git a/src/test/ui/impl-trait/issues/issue-70877.full_tait.stderr b/src/test/ui/impl-trait/issues/issue-70877.full_tait.stderr
@@ -6,6 +6,11 @@ LL | type FooRet = impl std::fmt::Debug;
 ...
 LL | type Foo = impl Iterator<Item = FooItem>;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected enum `Option`, found opaque type
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> Option<String> + 'static)>` here
    |
    = note: expected struct `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> Option<String> + 'static)>`
               found struct `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> impl Debug + 'static)>`
diff --git a/src/test/ui/impl-trait/issues/issue-70877.min_tait.stderr b/src/test/ui/impl-trait/issues/issue-70877.min_tait.stderr
@@ -6,6 +6,11 @@ LL | type FooRet = impl std::fmt::Debug;
 ...
 LL | type Foo = impl Iterator<Item = FooItem>;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected enum `Option`, found opaque type
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> Option<String> + 'static)>` here
    |
    = note: expected struct `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> Option<String> + 'static)>`
               found struct `Box<(dyn for<'r> Fn(&'r (dyn ToString + 'r)) -> impl Debug + 'static)>`
diff --git a/src/test/ui/impl-trait/projection-mismatch-in-impl-where-clause.stderr b/src/test/ui/impl-trait/projection-mismatch-in-impl-where-clause.stderr
@@ -1,6 +1,9 @@
 error[E0271]: type mismatch resolving `<() as Super>::Assoc == ()`
   --> $DIR/projection-mismatch-in-impl-where-clause.rs:13:14
    |
+LL |     type Assoc = u8;
+   |          ----- type mismatch with `()` here
+...
 LL | fn test() -> impl Test {
    |              ^^^^^^^^^ expected `()`, found `u8`
    |
diff --git a/src/test/ui/issues/issue-31173.stderr b/src/test/ui/issues/issue-31173.stderr
@@ -3,6 +3,11 @@ error[E0271]: type mismatch resolving `<TakeWhile<&mut std::vec::IntoIter<u8>, [
    |
 LL |         .cloned()
    |          ^^^^^^ expected `u8`, found reference
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `&_` here
    |
    = note:   expected type `u8`
            found reference `&_`
diff --git a/src/test/ui/issues/issue-33941.stderr b/src/test/ui/issues/issue-33941.stderr
@@ -3,6 +3,11 @@ error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _,
    |
 LL |     for _ in HashMap::new().iter().cloned() {}
    |                                    ^^^^^^ expected tuple, found reference
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `&_` here
    |
    = note:  expected tuple `(&_, &_)`
            found reference `&_`
@@ -12,6 +17,11 @@ error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _,
    |
 LL |     for _ in HashMap::new().iter().cloned() {}
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected reference, found tuple
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `&_` here
    |
    = note: expected reference `&_`
                   found tuple `(&_, &_)`
@@ -24,6 +34,11 @@ error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _,
    |
 LL |     for _ in HashMap::new().iter().cloned() {}
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected reference, found tuple
+   | 
+  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   |
+LL |     type Item = I::Item;
+   |          ---- type mismatch with `&_` here
    |
    = note: expected reference `&_`
                   found tuple `(&_, &_)`
diff --git a/src/test/ui/issues/issue-39970.stderr b/src/test/ui/issues/issue-39970.stderr
@@ -4,6 +4,9 @@ error[E0271]: type mismatch resolving `for<'a> <() as Array<'a>>::Element == ()`
 LL |     fn visit() {}
    |     ---------- required by `Visit::visit`
 ...
+LL |     type Element = &'a ();
+   |          ------- type mismatch with `()` here
+...
 LL |     <() as Visit>::visit();
    |     ^^^^^^^^^^^^^^^^^^^^ expected `()`, found `&()`
    |
diff --git a/src/test/ui/issues/issue-67039-unsound-pin-partialeq.stderr b/src/test/ui/issues/issue-67039-unsound-pin-partialeq.stderr
@@ -3,6 +3,11 @@ error[E0271]: type mismatch resolving `<Rc<Apple> as Deref>::Target == Rc<Apple>
    |
 LL |     let _ = Pin::new(Apple) == Rc::pin(Apple);
    |                             ^^ expected struct `Apple`, found struct `Rc`
+   | 
+  ::: $SRC_DIR/core/src/ops/deref.rs:LL:COL
+   |
+LL |     type Target = T;
+   |          ------ type mismatch with `Rc<Apple>` here
    |
    = note: expected type `Apple`
             found struct `Rc<Apple>`
diff --git a/src/test/ui/traits/assoc-type-in-superbad.stderr b/src/test/ui/traits/assoc-type-in-superbad.stderr
diff --git a/src/test/ui/traits/associated_type_bound/check-trait-object-bounds-5.stderr b/src/test/ui/traits/associated_type_bound/check-trait-object-bounds-5.stderr
diff --git a/src/test/ui/traits/associated_type_bound/check-trait-object-bounds-6.stderr b/src/test/ui/traits/associated_type_bound/check-trait-object-bounds-6.stderr
diff --git a/src/test/ui/try-block/try-block-bad-type.stderr b/src/test/ui/try-block/try-block-bad-type.stderr
diff --git a/src/test/ui/try-block/try-block-type-error.stderr b/src/test/ui/try-block/try-block-type-error.stderr
diff --git a/src/test/ui/type-alias-impl-trait/issue-63279.full_tait.stderr b/src/test/ui/type-alias-impl-trait/issue-63279.full_tait.stderr
diff --git a/src/test/ui/type-alias-impl-trait/issue-63279.min_tait.stderr b/src/test/ui/type-alias-impl-trait/issue-63279.min_tait.stderr

Original file line number	Diff line number	Diff line change
`@@ -16,6 +16,9 @@ LL \| fn foo2<I: Foo<A = Bar>>(x: I) {`
`16`	`16`	error[E0271]: type mismatch resolving `<isize as Foo>::A == Bar`
`17`	`17`	`--> $DIR/associated-types-eq-3.rs:38:5`
`18`	`18`	`\|`
	`19`	`+LL \| type A = usize;`
	`20`	+ \| - type mismatch with `Bar` here
	`21`	`+...`
`19`	`22`	`LL \| fn foo1<I: Foo<A=Bar>>(x: I) {`
`20`	`23`	\| ----- required by this bound in `foo1`
`21`	`24`	`...`
`@@ -25,6 +28,9 @@ LL \| foo1(a);`
`25`	`28`	error[E0271]: type mismatch resolving `<isize as Foo>::A == Bar`
`26`	`29`	`--> $DIR/associated-types-eq-3.rs:41:9`
`27`	`30`	`\|`
	`31`	`+LL \| type A = usize;`
	`32`	+ \| - type mismatch with `Bar` here
	`33`	`+...`
`28`	`34`	`LL \| baz(&a);`
`29`	`35`	\| ^^ expected struct `Bar`, found `usize`
`30`	`36`	`\|`
Original file line number	Diff line number	Diff line change
@@ -3,6 +3,11 @@ error[E0271]: type mismatch resolving `<std::vec::IntoIter<u32> as Iterator>::It
`3`	`3`	`\|`
`4`	`4`	`LL \| let _: &dyn I32Iterator<Item = u32> = &vec![42].into_iter();`
`5`	`5`	\| ^^^^^^^^^^^^^^^^^^^^^ expected `i32`, found `u32`
	`6`	`+ \|`
	`7`	`+ ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL`
	`8`	`+ \|`
	`9`	`+LL \| type Item = I::Item;`
	`10`	+ \| ---- type mismatch with `i32` here
`6`	`11`	`\|`
`7`	`12`	= note: required for the cast to the object type `dyn Iterator<Item = u32, Item = i32>`
`8`	`13`
Original file line number	Diff line number	Diff line change
@@ -36,6 +36,11 @@ error[E0271]: type mismatch resolving `<impl Future as Future>::Output == ()`
`36`	`36`	`\|`
`37`	`37`	`LL \| let _: &dyn Future<Output = ()> = &block;`
`38`	`38`	\| ^^^^^^ expected `()`, found `u8`
	`39`	`+ \|`
	`40`	`+ ::: $SRC_DIR/core/src/future/future.rs:LL:COL`
	`41`	`+ \|`
	`42`	`+LL \| type Output = F::Output;`
	`43`	+ \| ------ type mismatch with `()` here
`39`	`44`	`\|`
`40`	`45`	= note: required for the cast to the object type `dyn Future<Output = ()>`
`41`	`46`
@@ -52,6 +57,11 @@ error[E0271]: type mismatch resolving `<impl Future as Future>::Output == ()`
`52`	`57`	`\|`
`53`	`58`	`LL \| let _: &dyn Future<Output = ()> = &block;`
`54`	`59`	\| ^^^^^^ expected `()`, found `u8`
	`60`	`+ \|`
	`61`	`+ ::: $SRC_DIR/core/src/future/future.rs:LL:COL`
	`62`	`+ \|`
	`63`	`+LL \| type Output = F::Output;`
	`64`	+ \| ------ type mismatch with `()` here
`55`	`65`	`\|`
`56`	`66`	= note: required for the cast to the object type `dyn Future<Output = ()>`
`57`	`67`