Auto merge of #87668 - estebank:tweak-bound-output, r=oli-obk

Use note for pointing at bound introducing requirement

Modify output for pointing where a trait bound obligation is introduced in an E0277 from using a span label to using a note in order to always preserve order of the output:

Before:
```
error[E0277]: `<<Self as Case1>::A as Iterator>::Item` doesn't implement `Debug`
  --> $DIR/bounds-on-assoc-in-trait.rs:18:28
   |
LL |     type A: Iterator<Item: Debug>;
   |                            ^^^^^ `<<Self as Case1>::A as Iterator>::Item` cannot be formatted using `{:?}` because it doesn't implement `Debug`
   |
  ::: $SRC_DIR/core/src/fmt/mod.rs:LL:COL
   |
LL | pub trait Debug {
   | --------------- required by this bound in `Debug`
   |
   = help: the trait `Debug` is not implemented for `<<Self as Case1>::A as Iterator>::Item`
```
After:
```
error[E0277]: `<<Self as Case1>::A as Iterator>::Item` doesn't implement `Debug`
  --> $DIR/bounds-on-assoc-in-trait.rs:18:28
   |
LL |     type A: Iterator<Item: Debug>;
   |                            ^^^^^ `<<Self as Case1>::A as Iterator>::Item` cannot be formatted using `{:?}` because it doesn't implement `Debug`
   |
   = help: the trait `Debug` is not implemented for `<<Self as Case1>::A as Iterator>::Item`
note: required by a bound in `Debug`
  --> $SRC_DIR/core/src/fmt/mod.rs:LL:COL
   |
LL | pub trait Debug {
   | ^^^^^^^^^^^^^^^ required by this bound in `Debug`
```

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -1962,7 +1962,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
             }
             ObligationCauseCode::BindingObligation(item_def_id, span) => {
                 let item_name = tcx.def_path_str(item_def_id);
-                let msg = format!("required by this bound in `{}`", item_name);
+                let mut multispan = MultiSpan::from(span);
                 if let Some(ident) = tcx.opt_item_name(item_def_id) {
                     let sm = tcx.sess.source_map();
                     let same_line =
@@ -1971,16 +1971,17 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                             _ => true,
                         };
                     if !ident.span.overlaps(span) && !same_line {
-                        err.span_label(ident.span, "required by a bound in this");
+                        multispan
+                            .push_span_label(ident.span, "required by a bound in this".to_string());
                     }
                 }
+                let descr = format!("required by a bound in `{}`", item_name);
                 if span != DUMMY_SP {
-                    err.span_label(span, &msg);
+                    let msg = format!("required by this bound in `{}`", item_name);
+                    multispan.push_span_label(span, msg);
+                    err.span_note(multispan, &descr);
                 } else {
-                    err.span_note(
+                    err.span_note(tcx.def_span(item_def_id), &descr);
-                        tcx.def_span(item_def_id),
-                        &format!("required by a bound in `{}`", item_name),
-                    );
                 }
             }
             ObligationCauseCode::ObjectCastObligation(object_ty) => {

src/test/ui/anonymous-higher-ranked-lifetime.stderr

@@ -5,9 +5,12 @@ LL |     f1(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'r, 's> fn(&'r (), &'s ()) -> _`
-...
+   |
+note: required by a bound in `f1`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:16:25
+   |
 LL | fn f1<F>(_: F) where F: Fn(&(), &()) {}
-   |                         ------------ required by this bound in `f1`
+   |                         ^^^^^^^^^^^^ required by this bound in `f1`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:3:5
@@ -16,9 +19,12 @@ LL |     f2(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'a, 'r> fn(&'a (), &'r ()) -> _`
-...
+   |
+note: required by a bound in `f2`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:17:25
+   |
 LL | fn f2<F>(_: F) where F: for<'a> Fn(&'a (), &()) {}
-   |                         ----------------------- required by this bound in `f2`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `f2`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:4:5
@@ -27,9 +33,12 @@ LL |     f3(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'r> fn(&(), &'r ()) -> _`
-...
+   |
+note: required by a bound in `f3`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:18:29
+   |
 LL | fn f3<'a, F>(_: F) where F: Fn(&'a (), &()) {}
-   |                             --------------- required by this bound in `f3`
+   |                             ^^^^^^^^^^^^^^^ required by this bound in `f3`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:5:5
@@ -38,9 +47,12 @@ LL |     f4(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'s, 'r> fn(&'s (), &'r ()) -> _`
-...
+   |
+note: required by a bound in `f4`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:19:25
+   |
 LL | fn f4<F>(_: F) where F: for<'r> Fn(&(), &'r ()) {}
-   |                         ----------------------- required by this bound in `f4`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `f4`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:6:5
@@ -49,9 +61,12 @@ LL |     f5(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'r> fn(&'r (), &'r ()) -> _`
-...
+   |
+note: required by a bound in `f5`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:20:25
+   |
 LL | fn f5<F>(_: F) where F: for<'r> Fn(&'r (), &'r ()) {}
-   |                         -------------------------- required by this bound in `f5`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `f5`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:7:5
@@ -60,9 +75,12 @@ LL |     g1(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'r> fn(&'r (), Box<(dyn for<'s> Fn(&'s ()) + 'static)>) -> _`
-...
+   |
+note: required by a bound in `g1`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:23:25
+   |
 LL | fn g1<F>(_: F) where F: Fn(&(), Box<dyn Fn(&())>) {}
-   |                         ------------------------- required by this bound in `g1`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `g1`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:8:5
@@ -71,9 +89,12 @@ LL |     g2(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'r> fn(&'r (), for<'s> fn(&'s ())) -> _`
-...
+   |
+note: required by a bound in `g2`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:24:25
+   |
 LL | fn g2<F>(_: F) where F: Fn(&(), fn(&())) {}
-   |                         ---------------- required by this bound in `g2`
+   |                         ^^^^^^^^^^^^^^^^ required by this bound in `g2`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:9:5
@@ -82,9 +103,12 @@ LL |     g3(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'s> fn(&'s (), Box<(dyn for<'r> Fn(&'r ()) + 'static)>) -> _`
-...
+   |
+note: required by a bound in `g3`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:25:25
+   |
 LL | fn g3<F>(_: F) where F: for<'s> Fn(&'s (), Box<dyn Fn(&())>) {}
-   |                         ------------------------------------ required by this bound in `g3`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `g3`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:10:5
@@ -93,9 +117,12 @@ LL |     g4(|_: (), _: ()| {});
    |     ^^ -------------- found signature of `fn((), ()) -> _`
    |     |
    |     expected signature of `for<'s> fn(&'s (), for<'r> fn(&'r ())) -> _`
-...
+   |
+note: required by a bound in `g4`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:26:25
+   |
 LL | fn g4<F>(_: F) where F: Fn(&(), for<'r> fn(&'r ())) {}
-   |                         --------------------------- required by this bound in `g4`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `g4`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:11:5
@@ -104,9 +131,12 @@ LL |     h1(|_: (), _: (), _: (), _: ()| {});
    |     ^^ ---------------------------- found signature of `fn((), (), (), ()) -> _`
    |     |
    |     expected signature of `for<'r, 's> fn(&'r (), Box<(dyn for<'t0> Fn(&'t0 ()) + 'static)>, &'s (), for<'t0, 't1> fn(&'t0 (), &'t1 ())) -> _`
-...
+   |
+note: required by a bound in `h1`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:29:25
+   |
 LL | fn h1<F>(_: F) where F: Fn(&(), Box<dyn Fn(&())>, &(), fn(&(), &())) {}
-   |                         -------------------------------------------- required by this bound in `h1`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `h1`
 
 error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:12:5
@@ -115,9 +145,12 @@ LL |     h2(|_: (), _: (), _: (), _: ()| {});
    |     ^^ ---------------------------- found signature of `fn((), (), (), ()) -> _`
    |     |
    |     expected signature of `for<'r, 't0> fn(&'r (), Box<(dyn for<'s> Fn(&'s ()) + 'static)>, &'t0 (), for<'s, 't1> fn(&'s (), &'t1 ())) -> _`
-...
+   |
+note: required by a bound in `h2`
+  --> $DIR/anonymous-higher-ranked-lifetime.rs:30:25
+   |
 LL | fn h2<F>(_: F) where F: for<'t0> Fn(&(), Box<dyn Fn(&())>, &'t0 (), fn(&(), &())) {}
-   |                         --------------------------------------------------------- required by this bound in `h2`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `h2`
 
 error: aborting due to 11 previous errors
 

src/test/ui/associated-type-bounds/bad-bounds-on-assoc-in-trait.stderr

@@ -4,12 +4,12 @@ error[E0277]: `<<Self as Case1>::C as Iterator>::Item` cannot be sent between th
 LL |     type C: Clone + Iterator<Item: Send + Iterator<Item: for<'a> Lam<&'a u8, App: Debug>> + Sync>;
    |                                    ^^^^ `<<Self as Case1>::C as Iterator>::Item` cannot be sent between threads safely
    |
-  ::: $SRC_DIR/core/src/marker.rs:LL:COL
+   = help: the trait `Send` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
+note: required by a bound in `Send`
+  --> $SRC_DIR/core/src/marker.rs:LL:COL
    |
 LL | pub unsafe auto trait Send {
-   | -------------------------- required by this bound in `Send`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Send`
-   |
-   = help: the trait `Send` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::C as Iterator>::Item: Send {
@@ -21,12 +21,12 @@ error[E0277]: `<<Self as Case1>::C as Iterator>::Item` is not an iterator
 LL |     type C: Clone + Iterator<Item: Send + Iterator<Item: for<'a> Lam<&'a u8, App: Debug>> + Sync>;
    |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `<<Self as Case1>::C as Iterator>::Item` is not an iterator
    |
-  ::: $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+   = help: the trait `Iterator` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
+note: required by a bound in `Iterator`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
    |
 LL | pub trait Iterator {
-   | ------------------ required by this bound in `Iterator`
+   | ^^^^^^^^^^^^^^^^^^ required by this bound in `Iterator`
-   |
-   = help: the trait `Iterator` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::C as Iterator>::Item: Iterator {
@@ -38,12 +38,12 @@ error[E0277]: `<<Self as Case1>::C as Iterator>::Item` cannot be shared between
 LL |     type C: Clone + Iterator<Item: Send + Iterator<Item: for<'a> Lam<&'a u8, App: Debug>> + Sync>;
    |                                                                                             ^^^^ `<<Self as Case1>::C as Iterator>::Item` cannot be shared between threads safely
    |
-  ::: $SRC_DIR/core/src/marker.rs:LL:COL
+   = help: the trait `Sync` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
+note: required by a bound in `Sync`
+  --> $SRC_DIR/core/src/marker.rs:LL:COL
    |
 LL | pub unsafe auto trait Sync {
-   | -------------------------- required by this bound in `Sync`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Sync`
-   |
-   = help: the trait `Sync` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::C as Iterator>::Item: Sync {

src/test/ui/associated-type-bounds/bounds-on-assoc-in-trait.stderr

@@ -4,12 +4,12 @@ error[E0277]: `<<Self as Case1>::A as Iterator>::Item` doesn't implement `Debug`
 LL |     type A: Iterator<Item: Debug>;
    |                            ^^^^^ `<<Self as Case1>::A as Iterator>::Item` cannot be formatted using `{:?}` because it doesn't implement `Debug`
    |
-  ::: $SRC_DIR/core/src/fmt/mod.rs:LL:COL
+   = help: the trait `Debug` is not implemented for `<<Self as Case1>::A as Iterator>::Item`
+note: required by a bound in `Debug`
+  --> $SRC_DIR/core/src/fmt/mod.rs:LL:COL
    |
 LL | pub trait Debug {
-   | --------------- required by this bound in `Debug`
+   | ^^^^^^^^^^^^^^^ required by this bound in `Debug`
-   |
-   = help: the trait `Debug` is not implemented for `<<Self as Case1>::A as Iterator>::Item`
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::A as Iterator>::Item: Debug {
@@ -21,11 +21,11 @@ error[E0277]: the trait bound `<<Self as Foo>::Out as Baz>::Assoc: Default` is n
 LL | pub trait Foo { type Out: Baz<Assoc: Default>; }
    |                                      ^^^^^^^ the trait `Default` is not implemented for `<<Self as Foo>::Out as Baz>::Assoc`
    |
-  ::: $SRC_DIR/core/src/default.rs:LL:COL
+note: required by a bound in `Default`
+  --> $SRC_DIR/core/src/default.rs:LL:COL
    |
 LL | pub trait Default: Sized {
-   | ------------------------ required by this bound in `Default`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Default`
-   |
 help: consider further restricting the associated type
    |
 LL | pub trait Foo where <<Self as Foo>::Out as Baz>::Assoc: Default { type Out: Baz<Assoc: Default>; }

src/test/ui/associated-type-bounds/issue-83017.stderr

@@ -1,26 +1,32 @@
 error[E0277]: the trait bound `for<'a, 'b> <Z as TraitA<'a>>::AsA: TraitB<'a, 'b>` is not satisfied
   --> $DIR/issue-83017.rs:36:5
    |
+LL |     foo::<Z>();
+   |     ^^^^^^^^ the trait `for<'a, 'b> TraitB<'a, 'b>` is not implemented for `<Z as TraitA<'a>>::AsA`
+   |
+note: required by a bound in `foo`
+  --> $DIR/issue-83017.rs:31:32
+   |
 LL | fn foo<T>()
    |    --- required by a bound in this
 LL | where
 LL |     for<'a> T: TraitA<'a, AsA: for<'b> TraitB<'a, 'b, AsB: for<'c> TraitC<'a, 'b, 'c>>>,
-   |                                ------------------------------------------------------- required by this bound in `foo`
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
-...
-LL |     foo::<Z>();
-   |     ^^^^^^^^ the trait `for<'a, 'b> TraitB<'a, 'b>` is not implemented for `<Z as TraitA<'a>>::AsA`
 
 error[E0277]: the trait bound `for<'a, 'b, 'c> <<Z as TraitA<'a>>::AsA as TraitB<'a, 'b>>::AsB: TraitC<'a, 'b, 'c>` is not satisfied
   --> $DIR/issue-83017.rs:36:5
    |
+LL |     foo::<Z>();
+   |     ^^^^^^^^ the trait `for<'a, 'b, 'c> TraitC<'a, 'b, 'c>` is not implemented for `<<Z as TraitA<'a>>::AsA as TraitB<'a, 'b>>::AsB`
+   |
+note: required by a bound in `foo`
+  --> $DIR/issue-83017.rs:31:60
+   |
 LL | fn foo<T>()
    |    --- required by a bound in this
 LL | where
 LL |     for<'a> T: TraitA<'a, AsA: for<'b> TraitB<'a, 'b, AsB: for<'c> TraitC<'a, 'b, 'c>>>,
-   |                                                            -------------------------- required by this bound in `foo`
+   |                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
-...
-LL |     foo::<Z>();
-   |     ^^^^^^^^ the trait `for<'a, 'b, 'c> TraitC<'a, 'b, 'c>` is not implemented for `<<Z as TraitA<'a>>::AsA as TraitB<'a, 'b>>::AsB`
 
 error: aborting due to 2 previous errors
 

src/test/ui/associated-types/associated-types-binding-to-type-defined-in-supertrait.stderr

@@ -1,20 +1,26 @@
 error[E0271]: type mismatch resolving `<ModelT as Vehicle>::Color == Blue`
   --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:31:10
    |
-LL | fn blue_car<C:Car<Color=Blue>>(c: C) {
-   |                   ---------- required by this bound in `blue_car`
-...
 LL | fn b() { blue_car(ModelT); }
    |          ^^^^^^^^ expected struct `Blue`, found struct `Black`
+   |
+note: required by a bound in `blue_car`
+  --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:27:19
+   |
+LL | fn blue_car<C:Car<Color=Blue>>(c: C) {
+   |                   ^^^^^^^^^^ required by this bound in `blue_car`
 
 error[E0271]: type mismatch resolving `<ModelU as Vehicle>::Color == Black`
   --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:32:10
    |
-LL | fn black_car<C:Car<Color=Black>>(c: C) {
-   |                    ----------- required by this bound in `black_car`
-...
 LL | fn c() { black_car(ModelU); }
    |          ^^^^^^^^^ expected struct `Black`, found struct `Blue`
+   |
+note: required by a bound in `black_car`
+  --> $DIR/associated-types-binding-to-type-defined-in-supertrait.rs:24:20
+   |
+LL | fn black_car<C:Car<Color=Black>>(c: C) {
+   |                    ^^^^^^^^^^^ required by this bound in `black_car`
 
 error: aborting due to 2 previous errors
 

src/test/ui/associated-types/associated-types-eq-3.stderr

@@ -16,11 +16,14 @@ 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 | fn foo1<I: Foo<A=Bar>>(x: I) {
-   |                ----- required by this bound in `foo1`
-...
 LL |     foo1(a);
    |     ^^^^ expected struct `Bar`, found `usize`
+   |
+note: required by a bound in `foo1`
+  --> $DIR/associated-types-eq-3.rs:18:16
+   |
+LL | fn foo1<I: Foo<A=Bar>>(x: I) {
+   |                ^^^^^ required by this bound in `foo1`
 
 error[E0271]: type mismatch resolving `<isize as Foo>::A == Bar`
   --> $DIR/associated-types-eq-3.rs:41:9

src/test/ui/associated-types/associated-types-eq-hr.nll.stderr

@@ -1,32 +1,36 @@
 error[E0271]: type mismatch resolving `for<'x> <UintStruct as TheTrait<&'x isize>>::A == &'x isize`
   --> $DIR/associated-types-eq-hr.rs:87:5
    |
-LL | fn foo<T>()
-   |    --- required by a bound in this
-LL | where
-LL |     T: for<'x> TheTrait<&'x isize, A = &'x isize>,
-   |                                    ------------- required by this bound in `foo`
-...
 LL |     foo::<UintStruct>();
    |     ^^^^^^^^^^^^^^^^^ expected `isize`, found `usize`
    |
    = note: expected reference `&isize`
               found reference `&usize`
+note: required by a bound in `foo`
+  --> $DIR/associated-types-eq-hr.rs:45:36
+   |
+LL | fn foo<T>()
+   |    --- required by a bound in this
+LL | where
+LL |     T: for<'x> TheTrait<&'x isize, A = &'x isize>,
+   |                                    ^^^^^^^^^^^^^ required by this bound in `foo`
 
 error[E0271]: type mismatch resolving `for<'x> <IntStruct as TheTrait<&'x isize>>::A == &'x usize`
   --> $DIR/associated-types-eq-hr.rs:91:5
    |
-LL | fn bar<T>()
-   |    --- required by a bound in this
-LL | where
-LL |     T: for<'x> TheTrait<&'x isize, A = &'x usize>,
-   |                                    ------------- required by this bound in `bar`
-...
 LL |     bar::<IntStruct>();
    |     ^^^^^^^^^^^^^^^^ expected `usize`, found `isize`
    |
    = note: expected reference `&usize`
               found reference `&isize`
+note: required by a bound in `bar`
+  --> $DIR/associated-types-eq-hr.rs:52:36
+   |
+LL | fn bar<T>()
+   |    --- required by a bound in this
+LL | where
+LL |     T: for<'x> TheTrait<&'x isize, A = &'x usize>,
+   |                                    ^^^^^^^^^^^^^ required by this bound in `bar`
 
 error: aborting due to 2 previous errors
 

src/test/ui/associated-types/associated-types-eq-hr.stderr

@@ -1,32 +1,36 @@
 error[E0271]: type mismatch resolving `for<'x> <UintStruct as TheTrait<&'x isize>>::A == &'x isize`
   --> $DIR/associated-types-eq-hr.rs:87:5
    |
-LL | fn foo<T>()
-   |    --- required by a bound in this
-LL | where
-LL |     T: for<'x> TheTrait<&'x isize, A = &'x isize>,
-   |                                    ------------- required by this bound in `foo`
-...
 LL |     foo::<UintStruct>();
    |     ^^^^^^^^^^^^^^^^^ expected `isize`, found `usize`
    |
    = note: expected reference `&isize`
               found reference `&usize`
+note: required by a bound in `foo`
+  --> $DIR/associated-types-eq-hr.rs:45:36
+   |
+LL | fn foo<T>()
+   |    --- required by a bound in this
+LL | where
+LL |     T: for<'x> TheTrait<&'x isize, A = &'x isize>,
+   |                                    ^^^^^^^^^^^^^ required by this bound in `foo`
 
 error[E0271]: type mismatch resolving `for<'x> <IntStruct as TheTrait<&'x isize>>::A == &'x usize`
   --> $DIR/associated-types-eq-hr.rs:91:5
    |
-LL | fn bar<T>()
-   |    --- required by a bound in this
-LL | where
-LL |     T: for<'x> TheTrait<&'x isize, A = &'x usize>,
-   |                                    ------------- required by this bound in `bar`
-...
 LL |     bar::<IntStruct>();
    |     ^^^^^^^^^^^^^^^^ expected `usize`, found `isize`
    |
    = note: expected reference `&usize`
               found reference `&isize`
+note: required by a bound in `bar`
+  --> $DIR/associated-types-eq-hr.rs:52:36
+   |
+LL | fn bar<T>()
+   |    --- required by a bound in this
+LL | where
+LL |     T: for<'x> TheTrait<&'x isize, A = &'x usize>,
+   |                                    ^^^^^^^^^^^^^ required by this bound in `bar`
 
 error: implementation of `TheTrait` is not general enough
   --> $DIR/associated-types-eq-hr.rs:96:5

src/test/ui/associated-types/associated-types-for-unimpl-trait.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `Self: Get` is not satisfied
   --> $DIR/associated-types-for-unimpl-trait.rs:10:40
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) {}
    |                                        ^^^^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `Self`
    |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-for-unimpl-trait.rs:4:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 help: consider further restricting `Self`
    |
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) where Self: Get {}

src/test/ui/associated-types/associated-types-issue-20346.stderr

@@ -1,9 +1,6 @@
 error[E0271]: type mismatch resolving `<Adapter<I> as Iterator>::Item == Option<T>`
   --> $DIR/associated-types-issue-20346.rs:34:5
    |
-LL | fn is_iterator_of<A, I: Iterator<Item=A>>(_: &I) {}
-   |                                  ------ required by this bound in `is_iterator_of`
-...
 LL | fn test_adapter<T, I: Iterator<Item=Option<T>>>(it: I) {
    |                 - this type parameter
 ...
@@ -12,6 +9,11 @@ LL |     is_iterator_of::<Option<T>, _>(&adapter);
    |
    = note: expected enum `Option<T>`
               found type `T`
+note: required by a bound in `is_iterator_of`
+  --> $DIR/associated-types-issue-20346.rs:15:34
+   |
+LL | fn is_iterator_of<A, I: Iterator<Item=A>>(_: &I) {}
+   |                                  ^^^^^^ required by this bound in `is_iterator_of`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/associated-types-multiple-types-one-trait.stderr

@@ -3,12 +3,14 @@ error[E0271]: type mismatch resolving `<T as Foo>::Y == i32`
    |
 LL |     want_y(t);
    |     ^^^^^^ expected `i32`, found associated type
-...
-LL | fn want_y<T:Foo<Y=i32>>(t: &T) { }
-   |                 ----- required by this bound in `want_y`
    |
    = note:         expected type `i32`
            found associated type `<T as Foo>::Y`
+note: required by a bound in `want_y`
+  --> $DIR/associated-types-multiple-types-one-trait.rs:44:17
+   |
+LL | fn want_y<T:Foo<Y=i32>>(t: &T) { }
+   |                 ^^^^^ required by this bound in `want_y`
 help: consider constraining the associated type `<T as Foo>::Y` to `i32`
    |
 LL | fn have_x_want_y<T:Foo<X=u32, Y = i32>>(t: &T)
@@ -19,12 +21,14 @@ error[E0271]: type mismatch resolving `<T as Foo>::X == u32`
    |
 LL |     want_x(t);
    |     ^^^^^^ expected `u32`, found associated type
-...
-LL | fn want_x<T:Foo<X=u32>>(t: &T) { }
-   |                 ----- required by this bound in `want_x`
    |
    = note:         expected type `u32`
            found associated type `<T as Foo>::X`
+note: required by a bound in `want_x`
+  --> $DIR/associated-types-multiple-types-one-trait.rs:42:17
+   |
+LL | fn want_x<T:Foo<X=u32>>(t: &T) { }
+   |                 ^^^^^ required by this bound in `want_x`
 help: consider constraining the associated type `<T as Foo>::X` to `u32`
    |
 LL | fn have_y_want_x<T:Foo<Y=i32, X = u32>>(t: &T)

src/test/ui/associated-types/associated-types-no-suitable-bound.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `T: Get` is not satisfied
   --> $DIR/associated-types-no-suitable-bound.rs:11:21
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn uhoh<T>(foo: <T as Get>::Value) {}
    |                     ^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `T`
    |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-no-suitable-bound.rs:1:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 help: consider restricting type parameter `T`
    |
 LL |     fn uhoh<T: Get>(foo: <T as Get>::Value) {}

src/test/ui/associated-types/associated-types-no-suitable-supertrait-2.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `Self: Get` is not satisfied
   --> $DIR/associated-types-no-suitable-supertrait-2.rs:17:40
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) {}
    |                                        ^^^^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `Self`
    |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-no-suitable-supertrait-2.rs:12:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 help: consider further restricting `Self`
    |
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) where Self: Get {}

src/test/ui/associated-types/associated-types-no-suitable-supertrait.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `Self: Get` is not satisfied
   --> $DIR/associated-types-no-suitable-supertrait.rs:17:40
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) {}
    |                                        ^^^^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `Self`
    |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-no-suitable-supertrait.rs:12:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 help: consider further restricting `Self`
    |
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) where Self: Get {}
@@ -15,11 +17,14 @@ LL |     fn uhoh<U:Get>(&self, foo: U, bar: <Self as Get>::Value) where Self: Ge
 error[E0277]: the trait bound `(T, U): Get` is not satisfied
   --> $DIR/associated-types-no-suitable-supertrait.rs:22:40
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn uhoh<U:Get>(&self, foo: U, bar: <(T, U) as Get>::Value) {}
    |                                        ^^^^^^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `(T, U)`
+   |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-no-suitable-supertrait.rs:12:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 
 error: aborting due to 2 previous errors
 

src/test/ui/associated-types/associated-types-overridden-binding.stderr

@@ -1,18 +1,26 @@
 error[E0284]: type annotations needed: cannot satisfy `<Self as Iterator>::Item == i32`
   --> $DIR/associated-types-overridden-binding.rs:4:12
    |
-LL | trait Foo: Iterator<Item = i32> {}
-   |                     ---------- required by this bound in `Foo`
 LL | trait Bar: Foo<Item = u32> {}
    |            ^^^^^^^^^^^^^^^ cannot satisfy `<Self as Iterator>::Item == i32`
+   |
+note: required by a bound in `Foo`
+  --> $DIR/associated-types-overridden-binding.rs:3:21
+   |
+LL | trait Foo: Iterator<Item = i32> {}
+   |                     ^^^^^^^^^^ required by this bound in `Foo`
 
 error[E0284]: type annotations needed: cannot satisfy `<Self as Iterator>::Item == i32`
   --> $DIR/associated-types-overridden-binding.rs:7:21
    |
-LL | trait I32Iterator = Iterator<Item = i32>;
-   |                              ---------- required by this bound in `I32Iterator`
 LL | trait U32Iterator = I32Iterator<Item = u32>;
    |                     ^^^^^^^^^^^^^^^^^^^^^^^ cannot satisfy `<Self as Iterator>::Item == i32`
+   |
+note: required by a bound in `I32Iterator`
+  --> $DIR/associated-types-overridden-binding.rs:6:30
+   |
+LL | trait I32Iterator = Iterator<Item = i32>;
+   |                              ^^^^^^^^^^ required by this bound in `I32Iterator`
 
 error: aborting due to 2 previous errors
 

src/test/ui/associated-types/associated-types-path-2.stderr

@@ -12,11 +12,14 @@ LL |     f1(2i32, 4u32);
 error[E0277]: the trait bound `u32: Foo` is not satisfied
   --> $DIR/associated-types-path-2.rs:29:5
    |
-LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
-   |              --- required by this bound in `f1`
-...
 LL |     f1(2u32, 4u32);
    |     ^^ the trait `Foo` is not implemented for `u32`
+   |
+note: required by a bound in `f1`
+  --> $DIR/associated-types-path-2.rs:13:14
+   |
+LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
+   |              ^^^ required by this bound in `f1`
 
 error[E0277]: the trait bound `u32: Foo` is not satisfied
   --> $DIR/associated-types-path-2.rs:29:5
@@ -27,11 +30,14 @@ LL |     f1(2u32, 4u32);
 error[E0277]: the trait bound `u32: Foo` is not satisfied
   --> $DIR/associated-types-path-2.rs:35:5
    |
-LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
-   |              --- required by this bound in `f1`
-...
 LL |     f1(2u32, 4i32);
    |     ^^ the trait `Foo` is not implemented for `u32`
+   |
+note: required by a bound in `f1`
+  --> $DIR/associated-types-path-2.rs:13:14
+   |
+LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
+   |              ^^^ required by this bound in `f1`
 
 error[E0277]: the trait bound `u32: Foo` is not satisfied
   --> $DIR/associated-types-path-2.rs:35:5

src/test/ui/associated-types/associated-types-projection-to-unrelated-trait-in-method-without-default.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `Self: Get` is not satisfied
   --> $DIR/associated-types-projection-to-unrelated-trait-in-method-without-default.rs:10:40
    |
-LL | trait Get {
-   | --------- required by this bound in `Get`
-...
 LL |     fn okay<U:Get>(&self, foo: U, bar: <Self as Get>::Value);
    |                                        ^^^^^^^^^^^^^^^^^^^^ the trait `Get` is not implemented for `Self`
    |
+note: required by a bound in `Get`
+  --> $DIR/associated-types-projection-to-unrelated-trait-in-method-without-default.rs:5:1
+   |
+LL | trait Get {
+   | ^^^^^^^^^ required by this bound in `Get`
 help: consider further restricting `Self`
    |
 LL |     fn okay<U:Get>(&self, foo: U, bar: <Self as Get>::Value) where Self: Get;

src/test/ui/associated-types/defaults-suitability.stderr

@@ -2,33 +2,41 @@ error[E0277]: the trait bound `NotClone: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:13:5
    |
 LL |     type Ty: Clone = NotClone;
-   |     ^^^^^^^^^-----^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `NotClone`
-   |     |        |
+   |
-   |     |        required by this bound in `Tr::Ty`
+note: required by a bound in `Tr::Ty`
-   |     the trait `Clone` is not implemented for `NotClone`
+  --> $DIR/defaults-suitability.rs:13:14
+   |
+LL |     type Ty: Clone = NotClone;
+   |              ^^^^^ required by this bound in `Tr::Ty`
 
 error[E0277]: the trait bound `NotClone: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:22:5
    |
+LL |     type Ty = NotClone;
+   |     ^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `NotClone`
+   |
+note: required by a bound in `Tr2::Ty`
+  --> $DIR/defaults-suitability.rs:20:15
+   |
 LL |     Self::Ty: Clone,
-   |               ----- required by this bound in `Tr2::Ty`
+   |               ^^^^^ required by this bound in `Tr2::Ty`
 LL | {
 LL |     type Ty = NotClone;
-   |     ^^^^^--^^^^^^^^^^^^
+   |          -- required by a bound in this
-   |     |    |
-   |     |    required by a bound in this
-   |     the trait `Clone` is not implemented for `NotClone`
 
 error[E0277]: the trait bound `T: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:28:5
    |
 LL |     type Bar: Clone = Vec<T>;
-   |     ^^^^^^^^^^-----^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `T`
-   |     |         |
-   |     |         required by this bound in `Foo::Bar`
-   |     the trait `Clone` is not implemented for `T`
    |
    = note: required because of the requirements on the impl of `Clone` for `Vec<T>`
+note: required by a bound in `Foo::Bar`
+  --> $DIR/defaults-suitability.rs:28:15
+   |
+LL |     type Bar: Clone = Vec<T>;
+   |               ^^^^^ required by this bound in `Foo::Bar`
 help: consider restricting type parameter `T`
    |
 LL | trait Foo<T: std::clone::Clone> {
@@ -38,33 +46,41 @@ error[E0277]: the trait bound `(): Foo<Self>` is not satisfied
   --> $DIR/defaults-suitability.rs:34:5
    |
 LL |     type Assoc: Foo<Self> = ();
-   |     ^^^^^^^^^^^^---------^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Foo<Self>` is not implemented for `()`
-   |     |           |
+   |
-   |     |           required by this bound in `Bar::Assoc`
+note: required by a bound in `Bar::Assoc`
-   |     the trait `Foo<Self>` is not implemented for `()`
+  --> $DIR/defaults-suitability.rs:34:17
+   |
+LL |     type Assoc: Foo<Self> = ();
+   |                 ^^^^^^^^^ required by this bound in `Bar::Assoc`
 
 error[E0277]: the trait bound `NotClone: IsU8<NotClone>` is not satisfied
   --> $DIR/defaults-suitability.rs:56:5
    |
+LL |     type Assoc = NotClone;
+   |     ^^^^^^^^^^^^^^^^^^^^^^ the trait `IsU8<NotClone>` is not implemented for `NotClone`
+   |
+note: required by a bound in `D::Assoc`
+  --> $DIR/defaults-suitability.rs:53:18
+   |
 LL |     Self::Assoc: IsU8<Self::Assoc>,
-   |                  ----------------- required by this bound in `D::Assoc`
+   |                  ^^^^^^^^^^^^^^^^^ required by this bound in `D::Assoc`
 ...
 LL |     type Assoc = NotClone;
-   |     ^^^^^-----^^^^^^^^^^^^
+   |          ----- required by a bound in this
-   |     |    |
-   |     |    required by a bound in this
-   |     the trait `IsU8<NotClone>` is not implemented for `NotClone`
 
 error[E0277]: the trait bound `<Self as Foo2<T>>::Baz: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:65:5
    |
 LL |     type Bar: Clone = Vec<Self::Baz>;
-   |     ^^^^^^^^^^-----^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `<Self as Foo2<T>>::Baz`
-   |     |         |
-   |     |         required by this bound in `Foo2::Bar`
-   |     the trait `Clone` is not implemented for `<Self as Foo2<T>>::Baz`
    |
    = note: required because of the requirements on the impl of `Clone` for `Vec<<Self as Foo2<T>>::Baz>`
+note: required by a bound in `Foo2::Bar`
+  --> $DIR/defaults-suitability.rs:65:15
+   |
+LL |     type Bar: Clone = Vec<Self::Baz>;
+   |               ^^^^^ required by this bound in `Foo2::Bar`
 help: consider further restricting the associated type
    |
 LL | trait Foo2<T> where <Self as Foo2<T>>::Baz: Clone {
@@ -74,12 +90,14 @@ error[E0277]: the trait bound `<Self as Foo25<T>>::Baz: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:74:5
    |
 LL |     type Bar: Clone = Vec<Self::Baz>;
-   |     ^^^^^^^^^^-----^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `<Self as Foo25<T>>::Baz`
-   |     |         |
-   |     |         required by this bound in `Foo25::Bar`
-   |     the trait `Clone` is not implemented for `<Self as Foo25<T>>::Baz`
    |
    = note: required because of the requirements on the impl of `Clone` for `Vec<<Self as Foo25<T>>::Baz>`
+note: required by a bound in `Foo25::Bar`
+  --> $DIR/defaults-suitability.rs:74:15
+   |
+LL |     type Bar: Clone = Vec<Self::Baz>;
+   |               ^^^^^ required by this bound in `Foo25::Bar`
 help: consider further restricting the associated type
    |
 LL | trait Foo25<T: Clone> where <Self as Foo25<T>>::Baz: Clone {
@@ -88,15 +106,17 @@ LL | trait Foo25<T: Clone> where <Self as Foo25<T>>::Baz: Clone {
 error[E0277]: the trait bound `T: Clone` is not satisfied
   --> $DIR/defaults-suitability.rs:87:5
    |
+LL |     type Baz = T;
+   |     ^^^^^^^^^^^^^ the trait `Clone` is not implemented for `T`
+   |
+note: required by a bound in `Foo3::Baz`
+  --> $DIR/defaults-suitability.rs:84:16
+   |
 LL |     Self::Baz: Clone,
-   |                ----- required by this bound in `Foo3::Baz`
+   |                ^^^^^ required by this bound in `Foo3::Baz`
 ...
 LL |     type Baz = T;
-   |     ^^^^^---^^^^^
+   |          --- required by a bound in this
-   |     |    |
-   |     |    required by a bound in this
-   |     the trait `Clone` is not implemented for `T`
-   |
 help: consider further restricting type parameter `T`
    |
 LL |     Self::Baz: Clone, T: std::clone::Clone

src/test/ui/associated-types/defaults-unsound-62211-1.stderr

@@ -2,12 +2,14 @@ error[E0277]: `Self` doesn't implement `std::fmt::Display`
   --> $DIR/defaults-unsound-62211-1.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-------^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `Self` cannot be formatted with the default formatter
-   |     |                                                                                |
-   |     |                                                                                required by this bound in `UncheckedCopy::Output`
-   |     `Self` cannot be formatted with the default formatter
    |
    = note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-1.rs:20:86
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                                                                                      ^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + std::fmt::Display {
@@ -17,11 +19,13 @@ error[E0277]: cannot add-assign `&'static str` to `Self`
   --> $DIR/defaults-unsound-62211-1.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `Self += &'static str`
-   |     |                                         |
-   |     |                                         required by this bound in `UncheckedCopy::Output`
-   |     no implementation for `Self += &'static str`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-1.rs:20:47
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                                               ^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + AddAssign<&'static str> {
@@ -31,11 +35,13 @@ error[E0277]: the trait bound `Self: Deref` is not satisfied
   --> $DIR/defaults-unsound-62211-1.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^-------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Deref` is not implemented for `Self`
-   |     |                   |
-   |     |                   required by this bound in `UncheckedCopy::Output`
-   |     the trait `Deref` is not implemented for `Self`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-1.rs:20:25
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                         ^^^^^^^^^^^^^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + Deref {
@@ -45,11 +51,13 @@ error[E0277]: the trait bound `Self: Copy` is not satisfied
   --> $DIR/defaults-unsound-62211-1.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^----^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `Self`
-   |     |            |
-   |     |            required by this bound in `UncheckedCopy::Output`
-   |     the trait `Copy` is not implemented for `Self`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-1.rs:20:18
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                  ^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + Copy {

src/test/ui/associated-types/defaults-unsound-62211-2.stderr

@@ -2,12 +2,14 @@ error[E0277]: `Self` doesn't implement `std::fmt::Display`
   --> $DIR/defaults-unsound-62211-2.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-------^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `Self` cannot be formatted with the default formatter
-   |     |                                                                                |
-   |     |                                                                                required by this bound in `UncheckedCopy::Output`
-   |     `Self` cannot be formatted with the default formatter
    |
    = note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-2.rs:20:86
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                                                                                      ^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + std::fmt::Display {
@@ -17,11 +19,13 @@ error[E0277]: cannot add-assign `&'static str` to `Self`
   --> $DIR/defaults-unsound-62211-2.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `Self += &'static str`
-   |     |                                         |
-   |     |                                         required by this bound in `UncheckedCopy::Output`
-   |     no implementation for `Self += &'static str`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-2.rs:20:47
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                                               ^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + AddAssign<&'static str> {
@@ -31,11 +35,13 @@ error[E0277]: the trait bound `Self: Deref` is not satisfied
   --> $DIR/defaults-unsound-62211-2.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^^^^^^^^-------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Deref` is not implemented for `Self`
-   |     |                   |
-   |     |                   required by this bound in `UncheckedCopy::Output`
-   |     the trait `Deref` is not implemented for `Self`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-2.rs:20:25
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                         ^^^^^^^^^^^^^^^^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + Deref {
@@ -45,11 +51,13 @@ error[E0277]: the trait bound `Self: Copy` is not satisfied
   --> $DIR/defaults-unsound-62211-2.rs:20:5
    |
 LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
-   |     ^^^^^^^^^^^^^----^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `Self`
-   |     |            |
-   |     |            required by this bound in `UncheckedCopy::Output`
-   |     the trait `Copy` is not implemented for `Self`
    |
+note: required by a bound in `UncheckedCopy::Output`
+  --> $DIR/defaults-unsound-62211-2.rs:20:18
+   |
+LL |     type Output: Copy + Deref<Target = str> + AddAssign<&'static str> + From<Self> + Display = Self;
+   |                  ^^^^ required by this bound in `UncheckedCopy::Output`
 help: consider further restricting `Self`
    |
 LL | trait UncheckedCopy: Sized + Copy {

src/test/ui/associated-types/defaults-wf.stderr

@@ -4,12 +4,12 @@ error[E0277]: the size for values of type `[u8]` cannot be known at compilation
 LL |     type Ty = Vec<[u8]>;
    |               ^^^^^^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
+   = help: the trait `Sized` is not implemented for `[u8]`
+note: required by a bound in `Vec`
+  --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
    |
 LL | pub struct Vec<T, #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global> {
-   |                - required by this bound in `Vec`
+   |                ^ required by this bound in `Vec`
-   |
-   = help: the trait `Sized` is not implemented for `[u8]`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-1.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the trait bound `for<'b> <i32 as X<'b>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-1.rs:12:14
    |
-LL | trait X<'a>
-   |       - required by a bound in this
-LL | where
-LL |     for<'b> <Self as X<'b>>::U: Clone,
-   |                                 ----- required by this bound in `X`
-...
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<i32 as X<'b>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-1.rs:3:33
+   |
+LL | trait X<'a>
+   |       - required by a bound in this
+LL | where
+LL |     for<'b> <Self as X<'b>>::U: Clone,
+   |                                 ^^^^^ required by this bound in `X`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-object.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the trait bound `for<'b> <T as X<'b>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-object.rs:7:13
    |
-LL | trait X<'a>
-   |       - required by a bound in this
-LL | where
-LL |     for<'b> <Self as X<'b>>::U: Clone,
-   |                                 ----- required by this bound in `X`
-...
 LL | fn f<'a, T: X<'a> + ?Sized>(x: &<T as X<'a>>::U) {
    |             ^^^^^ the trait `for<'b> Clone` is not implemented for `<T as X<'b>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-object.rs:3:33
+   |
+LL | trait X<'a>
+   |       - required by a bound in this
+LL | where
+LL |     for<'b> <Self as X<'b>>::U: Clone,
+   |                                 ^^^^^ required by this bound in `X`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-param-1.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the trait bound `for<'b> <u8 as Y<'b, u8>>::V: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-1.rs:14:14
    |
-LL | trait Y<'a, T: ?Sized>
-   |       - required by a bound in this
-...
-LL |     for<'b> <Self as Y<'b, T>>::V: Clone,
-   |                                    ----- required by this bound in `Y`
-...
 LL |     type V = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<u8 as Y<'b, u8>>::V`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `Y`
+  --> $DIR/hr-associated-type-bound-param-1.rs:4:36
+   |
+LL | trait Y<'a, T: ?Sized>
+   |       - required by a bound in this
+...
+LL |     for<'b> <Self as Y<'b, T>>::V: Clone,
+   |                                    ^^^^^ required by this bound in `Y`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-param-2.stderr

@@ -1,47 +1,53 @@
 error[E0277]: the trait bound `for<'b> <u16 as Z<'b, u16>>::W: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-2.rs:4:8
    |
-LL | trait Z<'a, T: ?Sized>
-   |       - required by a bound in this
-LL | where
 LL |     T: Z<'a, u16>,
    |        ^^^^^^^^^^ the trait `for<'b> Clone` is not implemented for `<u16 as Z<'b, u16>>::W`
-...
-LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
-   |                                   ----- required by this bound in `Z`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `Z`
+  --> $DIR/hr-associated-type-bound-param-2.rs:7:35
+   |
+LL | trait Z<'a, T: ?Sized>
+   |       - required by a bound in this
+...
+LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
+   |                                   ^^^^^ required by this bound in `Z`
 
 error[E0277]: the trait bound `for<'b> <u16 as Z<'b, u16>>::W: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-2.rs:4:8
    |
-LL | trait Z<'a, T: ?Sized>
-   |       - required by a bound in this
-LL | where
 LL |     T: Z<'a, u16>,
    |        ^^^^^^^^^^ the trait `for<'b> Clone` is not implemented for `<u16 as Z<'b, u16>>::W`
-...
-LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
-   |                                   ----- required by this bound in `Z`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `Z`
+  --> $DIR/hr-associated-type-bound-param-2.rs:7:35
+   |
+LL | trait Z<'a, T: ?Sized>
+   |       - required by a bound in this
+...
+LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
+   |                                   ^^^^^ required by this bound in `Z`
 
 error[E0277]: the trait bound `for<'b> <u16 as Z<'b, u16>>::W: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-2.rs:16:14
    |
-LL | trait Z<'a, T: ?Sized>
-   |       - required by a bound in this
-...
-LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
-   |                                   ----- required by this bound in `Z`
-...
 LL |     type W = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<u16 as Z<'b, u16>>::W`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `Z`
+  --> $DIR/hr-associated-type-bound-param-2.rs:7:35
+   |
+LL | trait Z<'a, T: ?Sized>
+   |       - required by a bound in this
+...
+LL |     for<'b> <T as Z<'b, u16>>::W: Clone,
+   |                                   ^^^^^ required by this bound in `Z`
 
 error: aborting due to 3 previous errors
 

src/test/ui/associated-types/hr-associated-type-bound-param-3.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the trait bound `for<'b> <(T,) as X<'b, (T,)>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-3.rs:13:14
    |
-LL | trait X<'a, T>
-   |       - required by a bound in this
-...
-LL |     for<'b> <T as X<'b, T>>::U: Clone,
-   |                                 ----- required by this bound in `X`
-...
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<(T,) as X<'b, (T,)>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-3.rs:4:33
+   |
+LL | trait X<'a, T>
+   |       - required by a bound in this
+...
+LL |     for<'b> <T as X<'b, T>>::U: Clone,
+   |                                 ^^^^^ required by this bound in `X`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-param-4.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the trait bound `for<'b> <(T,) as X<'b, T>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-4.rs:13:14
    |
-LL | trait X<'a, T>
-   |       - required by a bound in this
-...
-LL |     for<'b> <(T,) as X<'b, T>>::U: Clone,
-   |                                    ----- required by this bound in `X`
-...
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<(T,) as X<'b, T>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-4.rs:4:36
+   |
+LL | trait X<'a, T>
+   |       - required by a bound in this
+...
+LL |     for<'b> <(T,) as X<'b, T>>::U: Clone,
+   |                                    ^^^^^ required by this bound in `X`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/hr-associated-type-bound-param-5.stderr

@@ -1,62 +1,70 @@
 error[E0277]: the trait bound `for<'b> <Box<T> as X<'b, Box<T>>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-5.rs:27:14
    |
-LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
-   |       - required by a bound in this
-...
-LL |     for<'b> <T::Next as X<'b, T::Next>>::U: Clone,
-   |                                             ----- required by this bound in `X`
-...
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<Box<T> as X<'b, Box<T>>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
-
+note: required by a bound in `X`
-error[E0277]: the trait bound `for<'b> <Vec<T> as X<'b, Vec<T>>>::U: Clone` is not satisfied
+  --> $DIR/hr-associated-type-bound-param-5.rs:18:45
-  --> $DIR/hr-associated-type-bound-param-5.rs:27:14
-   |
-LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
-   |       - required by a bound in this
-LL | where
-LL |     for<'b> <T as X<'b, T>>::U: Clone,
-   |                                 ----- required by this bound in `X`
-...
-LL |     type U = str;
-   |              ^^^ the trait `for<'b> Clone` is not implemented for `<Vec<T> as X<'b, Vec<T>>>::U`
-   |
-   = help: the following implementations were found:
-             <&T as Clone>
-
-error[E0277]: the trait bound `for<'b> <Vec<T> as X<'b, Vec<T>>>::U: Clone` is not satisfied
-  --> $DIR/hr-associated-type-bound-param-5.rs:33:14
    |
 LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
    |       - required by a bound in this
 ...
 LL |     for<'b> <T::Next as X<'b, T::Next>>::U: Clone,
-   |                                             ----- required by this bound in `X`
+   |                                             ^^^^^ required by this bound in `X`
-...
+
+error[E0277]: the trait bound `for<'b> <Vec<T> as X<'b, Vec<T>>>::U: Clone` is not satisfied
+  --> $DIR/hr-associated-type-bound-param-5.rs:27:14
+   |
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<Vec<T> as X<'b, Vec<T>>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
-
+note: required by a bound in `X`
-error[E0277]: the trait bound `for<'b> <Box<T> as X<'b, Box<T>>>::U: Clone` is not satisfied
+  --> $DIR/hr-associated-type-bound-param-5.rs:16:33
-  --> $DIR/hr-associated-type-bound-param-5.rs:33:14
    |
 LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
    |       - required by a bound in this
 LL | where
 LL |     for<'b> <T as X<'b, T>>::U: Clone,
-   |                                 ----- required by this bound in `X`
+   |                                 ^^^^^ required by this bound in `X`
+
+error[E0277]: the trait bound `for<'b> <Vec<T> as X<'b, Vec<T>>>::U: Clone` is not satisfied
+  --> $DIR/hr-associated-type-bound-param-5.rs:33:14
+   |
+LL |     type U = str;
+   |              ^^^ the trait `for<'b> Clone` is not implemented for `<Vec<T> as X<'b, Vec<T>>>::U`
+   |
+   = help: the following implementations were found:
+             <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-5.rs:18:45
+   |
+LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
+   |       - required by a bound in this
 ...
+LL |     for<'b> <T::Next as X<'b, T::Next>>::U: Clone,
+   |                                             ^^^^^ required by this bound in `X`
+
+error[E0277]: the trait bound `for<'b> <Box<T> as X<'b, Box<T>>>::U: Clone` is not satisfied
+  --> $DIR/hr-associated-type-bound-param-5.rs:33:14
+   |
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<Box<T> as X<'b, Box<T>>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-5.rs:16:33
+   |
+LL | trait X<'a, T: Cycle + for<'b> X<'b, T>>
+   |       - required by a bound in this
+LL | where
+LL |     for<'b> <T as X<'b, T>>::U: Clone,
+   |                                 ^^^^^ required by this bound in `X`
 
 error: aborting due to 4 previous errors
 

src/test/ui/associated-types/hr-associated-type-bound-param-6.stderr

@@ -1,30 +1,34 @@
 error[E0277]: the trait bound `for<'b> <T as X<'b, T>>::U: Clone` is not satisfied
   --> $DIR/hr-associated-type-bound-param-6.rs:14:14
    |
-LL | trait X<'a, T>
-   |       - required by a bound in this
-...
-LL |     for<'b> <T as X<'b, T>>::U: Clone,
-   |                                 ----- required by this bound in `X`
-...
 LL |     type U = str;
    |              ^^^ the trait `for<'b> Clone` is not implemented for `<T as X<'b, T>>::U`
    |
    = help: the following implementations were found:
              <&T as Clone>
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-6.rs:4:33
+   |
+LL | trait X<'a, T>
+   |       - required by a bound in this
+...
+LL |     for<'b> <T as X<'b, T>>::U: Clone,
+   |                                 ^^^^^ required by this bound in `X`
 
 error[E0277]: the trait bound `for<'b> T: X<'b, T>` is not satisfied
   --> $DIR/hr-associated-type-bound-param-6.rs:12:12
    |
+LL | impl<S, T> X<'_, T> for (S,) {
+   |            ^^^^^^^^ the trait `for<'b> X<'b, T>` is not implemented for `T`
+   |
+note: required by a bound in `X`
+  --> $DIR/hr-associated-type-bound-param-6.rs:3:16
+   |
 LL | trait X<'a, T>
    |       - required by a bound in this
 LL | where
 LL |     for<'b> T: X<'b, T>,
-   |                -------- required by this bound in `X`
+   |                ^^^^^^^^ required by this bound in `X`
-...
-LL | impl<S, T> X<'_, T> for (S,) {
-   |            ^^^^^^^^ the trait `for<'b> X<'b, T>` is not implemented for `T`
-   |
 help: consider restricting type parameter `T`
    |
 LL | impl<S, T: for<'b> X<'b, T>> X<'_, T> for (S,) {

src/test/ui/associated-types/hr-associated-type-projection-1.stderr

@@ -1,18 +1,20 @@
 error[E0277]: the trait bound `for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
   --> $DIR/hr-associated-type-projection-1.rs:15:17
    |
-LL | trait UnsafeCopy<'a, T: Copy>
-   |       ---------- required by a bound in this
-LL | where
-LL |     for<'b> <Self as UnsafeCopy<'b, T>>::Item: std::ops::Deref<Target = T>,
-   |                                                --------------------------- required by this bound in `UnsafeCopy`
-...
 LL |     type Item = T;
    |                 ^ the trait `for<'b> Deref` is not implemented for `<T as UnsafeCopy<'b, T>>::Item`
    |
    = help: the following implementations were found:
              <&T as Deref>
              <&mut T as Deref>
+note: required by a bound in `UnsafeCopy`
+  --> $DIR/hr-associated-type-projection-1.rs:3:48
+   |
+LL | trait UnsafeCopy<'a, T: Copy>
+   |       ---------- required by a bound in this
+LL | where
+LL |     for<'b> <Self as UnsafeCopy<'b, T>>::Item: std::ops::Deref<Target = T>,
+   |                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `UnsafeCopy`
 
 error[E0277]: the trait bound `for<'b> <T as UnsafeCopy<'b, T>>::Item: Deref` is not satisfied
   --> $DIR/hr-associated-type-projection-1.rs:13:33

src/test/ui/associated-types/issue-20005.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the size for values of type `Self` cannot be known at compilation time
   --> $DIR/issue-20005.rs:10:49
    |
-LL | trait From<Src> {
-   |            --- required by this bound in `From`
-...
 LL |     ) -> <Dst as From<Self>>::Result where Dst: From<Self> {
    |                                                 ^^^^^^^^^^ doesn't have a size known at compile-time
    |
+note: required by a bound in `From`
+  --> $DIR/issue-20005.rs:1:12
+   |
+LL | trait From<Src> {
+   |            ^^^ required by this bound in `From`
 help: consider further restricting `Self`
    |
 LL |     ) -> <Dst as From<Self>>::Result where Dst: From<Self>, Self: Sized {

src/test/ui/associated-types/issue-27675-unchecked-bounds.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `T: Copy` is not satisfied
   --> $DIR/issue-27675-unchecked-bounds.rs:15:31
    |
-LL | fn copy<U: Setup + ?Sized>(from: &U::From) -> U::From {
-   |            ----- required by this bound in `copy`
-...
 LL |     copy::<dyn Setup<From=T>>(t)
    |                               ^ the trait `Copy` is not implemented for `T`
    |
+note: required by a bound in `copy`
+  --> $DIR/issue-27675-unchecked-bounds.rs:10:12
+   |
+LL | fn copy<U: Setup + ?Sized>(from: &U::From) -> U::From {
+   |            ^^^^^ required by this bound in `copy`
 help: consider restricting type parameter `T`
    |
 LL | pub fn copy_any<T: std::marker::Copy>(t: &T) -> T {

src/test/ui/associated-types/issue-43784-associated-type.stderr

@@ -1,12 +1,14 @@
 error[E0277]: the trait bound `T: Copy` is not satisfied
   --> $DIR/issue-43784-associated-type.rs:14:5
    |
-LL |     type Assoc: Partial<Self>;
-   |                 ------------- required by this bound in `Complete::Assoc`
-...
 LL |     type Assoc = T;
    |     ^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `T`
    |
+note: required by a bound in `Complete::Assoc`
+  --> $DIR/issue-43784-associated-type.rs:5:17
+   |
+LL |     type Assoc: Partial<Self>;
+   |                 ^^^^^^^^^^^^^ required by this bound in `Complete::Assoc`
 help: consider restricting type parameter `T`
    |
 LL | impl<T: std::marker::Copy> Complete for T {

src/test/ui/associated-types/issue-43924.stderr

@@ -2,10 +2,13 @@ error[E0277]: the trait bound `(dyn ToString + 'static): Default` is not satisfi
   --> $DIR/issue-43924.rs:7:5
    |
 LL |     type Out: Default + ToString + ?Sized = dyn ToString;
-   |     ^^^^^^^^^^-------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Default` is not implemented for `(dyn ToString + 'static)`
-   |     |         |
+   |
-   |     |         required by this bound in `Foo::Out`
+note: required by a bound in `Foo::Out`
-   |     the trait `Default` is not implemented for `(dyn ToString + 'static)`
+  --> $DIR/issue-43924.rs:7:15
+   |
+LL |     type Out: Default + ToString + ?Sized = dyn ToString;
+   |               ^^^^^^^ required by this bound in `Foo::Out`
 
 error[E0599]: no function or associated item named `default` found for trait object `(dyn ToString + 'static)` in the current scope
   --> $DIR/issue-43924.rs:14:39

src/test/ui/associated-types/issue-54108.stderr

@@ -1,13 +1,15 @@
 error[E0277]: cannot add `<T as SubEncoder>::ActualSize` to `<T as SubEncoder>::ActualSize`
   --> $DIR/issue-54108.rs:19:5
    |
-LL |     type Size: Add<Output = Self::Size>;
-   |                ------------------------ required by this bound in `Encoder::Size`
-...
 LL |     type Size = <Self as SubEncoder>::ActualSize;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `<T as SubEncoder>::ActualSize + <T as SubEncoder>::ActualSize`
    |
    = help: the trait `Add` is not implemented for `<T as SubEncoder>::ActualSize`
+note: required by a bound in `Encoder::Size`
+  --> $DIR/issue-54108.rs:4:16
+   |
+LL |     type Size: Add<Output = Self::Size>;
+   |                ^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Encoder::Size`
 help: consider further restricting the associated type
    |
 LL |     T: SubEncoder, <T as SubEncoder>::ActualSize: Add

src/test/ui/associated-types/issue-63593.stderr

@@ -2,11 +2,13 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
   --> $DIR/issue-63593.rs:9:5
    |
 LL |     type This = Self;
-   |     ^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
-   |     |
-   |     doesn't have a size known at compile-time
-   |     required by this bound in `MyTrait::This`
    |
+note: required by a bound in `MyTrait::This`
+  --> $DIR/issue-63593.rs:9:5
+   |
+LL |     type This = Self;
+   |     ^^^^^^^^^^^^^^^^^ required by this bound in `MyTrait::This`
 help: consider further restricting `Self`
    |
 LL | trait MyTrait: Sized {

src/test/ui/associated-types/issue-65774-1.stderr

@@ -2,10 +2,13 @@ error[E0277]: the trait bound `T: MyDisplay` is not satisfied
   --> $DIR/issue-65774-1.rs:10:5
    |
 LL |     type MpuConfig: MyDisplay = T;
-   |     ^^^^^^^^^^^^^^^^---------^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `MyDisplay` is not implemented for `T`
-   |     |               |
+   |
-   |     |               required by this bound in `MPU::MpuConfig`
+note: required by a bound in `MPU::MpuConfig`
-   |     the trait `MyDisplay` is not implemented for `T`
+  --> $DIR/issue-65774-1.rs:10:21
+   |
+LL |     type MpuConfig: MyDisplay = T;
+   |                     ^^^^^^^^^ required by this bound in `MPU::MpuConfig`
 
 error[E0277]: the trait bound `T: MyDisplay` is not satisfied
   --> $DIR/issue-65774-1.rs:44:76

src/test/ui/associated-types/issue-65774-2.stderr

@@ -2,10 +2,13 @@ error[E0277]: the trait bound `T: MyDisplay` is not satisfied
   --> $DIR/issue-65774-2.rs:10:5
    |
 LL |     type MpuConfig: MyDisplay = T;
-   |     ^^^^^^^^^^^^^^^^---------^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `MyDisplay` is not implemented for `T`
-   |     |               |
+   |
-   |     |               required by this bound in `MPU::MpuConfig`
+note: required by a bound in `MPU::MpuConfig`
-   |     the trait `MyDisplay` is not implemented for `T`
+  --> $DIR/issue-65774-2.rs:10:21
+   |
+LL |     type MpuConfig: MyDisplay = T;
+   |                     ^^^^^^^^^ required by this bound in `MPU::MpuConfig`
 
 error[E0277]: the trait bound `T: MyDisplay` is not satisfied
   --> $DIR/issue-65774-2.rs:39:25

src/test/ui/associated-types/issue-72806.stderr

@@ -1,11 +1,14 @@
 error[E0271]: type mismatch resolving `<Foo2 as Bar2>::Ok == char`
   --> $DIR/issue-72806.rs:14:5
    |
-LL |     type Sibling: Bar2<Ok=char>;
-   |                        ------- required by this bound in `Bar::Sibling`
-...
 LL |     type Sibling = Foo2;
    |     ^^^^^^^^^^^^^^^^^^^^ expected `char`, found `u32`
+   |
+note: required by a bound in `Bar::Sibling`
+  --> $DIR/issue-72806.rs:3:24
+   |
+LL |     type Sibling: Bar2<Ok=char>;
+   |                        ^^^^^^^ required by this bound in `Bar::Sibling`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/issue-87261.stderr

@@ -1,14 +1,16 @@
 error[E0271]: type mismatch resolving `<A as Trait>::Associated == ()`
   --> $DIR/issue-87261.rs:56:5
    |
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(a);
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<A as Trait>::Associated`
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 help: consider constraining the associated type `<A as Trait>::Associated` to `()`
    |
 LL |     A: Trait<Associated = ()> + 'static,
@@ -17,9 +19,6 @@ LL |     A: Trait<Associated = ()> + 'static,
 error[E0271]: type mismatch resolving `<B as Trait>::Associated == ()`
   --> $DIR/issue-87261.rs:59:5
    |
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(b);
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
@@ -27,18 +26,25 @@ LL |     accepts_trait(b);
            found associated type `<B as Trait>::Associated`
    = help: consider constraining the associated type `<B as Trait>::Associated` to `()`
    = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 
 error[E0271]: type mismatch resolving `<C as Trait>::Associated == ()`
   --> $DIR/issue-87261.rs:62:5
    |
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(c);
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<C as Trait>::Associated`
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 help: consider constraining the associated type `<C as Trait>::Associated` to `()`
    |
 LL |     C: Trait<Associated = ()> + Foo,
@@ -47,9 +53,6 @@ LL |     C: Trait<Associated = ()> + Foo,
 error[E0271]: type mismatch resolving `<D as Trait>::Associated == ()`
   --> $DIR/issue-87261.rs:65:5
    |
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(d);
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
@@ -57,18 +60,25 @@ LL |     accepts_trait(d);
            found associated type `<D as Trait>::Associated`
    = help: consider constraining the associated type `<D as Trait>::Associated` to `()`
    = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 
 error[E0271]: type mismatch resolving `<E as GenericTrait<()>>::Associated == ()`
   --> $DIR/issue-87261.rs:68:5
    |
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(e);
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<E as GenericTrait<()>>::Associated`
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 help: consider constraining the associated type `<E as GenericTrait<()>>::Associated` to `()`
    |
 LL |     E: GenericTrait<(), Associated = ()> + 'static,
@@ -77,14 +87,16 @@ LL |     E: GenericTrait<(), Associated = ()> + 'static,
 error[E0271]: type mismatch resolving `<F as GenericTrait<()>>::Associated == ()`
   --> $DIR/issue-87261.rs:71:5
    |
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(f);
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<F as GenericTrait<()>>::Associated`
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 help: consider constraining the associated type `<F as GenericTrait<()>>::Associated` to `()`
    |
 LL |     F: GenericTrait<(), Associated = ()> + Foo,
@@ -93,9 +105,6 @@ LL |     F: GenericTrait<(), Associated = ()> + Foo,
 error[E0271]: type mismatch resolving `<G as GenericTrait<()>>::Associated == ()`
   --> $DIR/issue-87261.rs:74:5
    |
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(g);
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
@@ -103,6 +112,11 @@ LL |     accepts_generic_trait(g);
            found associated type `<G as GenericTrait<()>>::Associated`
    = help: consider constraining the associated type `<G as GenericTrait<()>>::Associated` to `()`
    = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 
 error[E0271]: type mismatch resolving `<impl Trait as Trait>::Associated == ()`
   --> $DIR/issue-87261.rs:79:5
@@ -110,14 +124,16 @@ error[E0271]: type mismatch resolving `<impl Trait as Trait>::Associated == ()`
 LL | fn returns_opaque() -> impl Trait + 'static {
    |                        -------------------- the found opaque type
 ...
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(returns_opaque());
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<impl Trait as Trait>::Associated`
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 help: consider constraining the associated type `<impl Trait as Trait>::Associated` to `()`
    |
 LL | fn returns_opaque() -> impl Trait<Associated = ()> + 'static {
@@ -129,14 +145,16 @@ error[E0271]: type mismatch resolving `<impl DerivedTrait as Trait>::Associated
 LL | fn returns_opaque_derived() -> impl DerivedTrait + 'static {
    |                                --------------------------- the found opaque type
 ...
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(returns_opaque_derived());
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<impl DerivedTrait as Trait>::Associated`
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 help: consider constraining the associated type `<impl DerivedTrait as Trait>::Associated` to `()`
    |
 LL | fn returns_opaque_derived() -> impl DerivedTrait<Associated = ()> + 'static {
@@ -148,14 +166,16 @@ error[E0271]: type mismatch resolving `<impl Trait+Foo as Trait>::Associated ==
 LL | fn returns_opaque_foo() -> impl Trait + Foo {
    |                            ---------------- the found opaque type
 ...
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(returns_opaque_foo());
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<impl Trait+Foo as Trait>::Associated`
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 help: consider constraining the associated type `<impl Trait+Foo as Trait>::Associated` to `()`
    |
 LL | fn returns_opaque_foo() -> impl Trait<Associated = ()> + Foo {
@@ -167,9 +187,6 @@ error[E0271]: type mismatch resolving `<impl DerivedTrait+Foo as Trait>::Associa
 LL | fn returns_opaque_derived_foo() -> impl DerivedTrait + Foo {
    |                                    ----------------------- the found opaque type
 ...
-LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
-   |                           --------------- required by this bound in `accepts_trait`
-...
 LL |     accepts_trait(returns_opaque_derived_foo());
    |     ^^^^^^^^^^^^^ expected `()`, found associated type
    |
@@ -177,6 +194,11 @@ LL |     accepts_trait(returns_opaque_derived_foo());
            found associated type `<impl DerivedTrait+Foo as Trait>::Associated`
    = help: consider constraining the associated type `<impl DerivedTrait+Foo as Trait>::Associated` to `()`
    = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: required by a bound in `accepts_trait`
+  --> $DIR/issue-87261.rs:43:27
+   |
+LL | fn accepts_trait<T: Trait<Associated = ()>>(_: T) {}
+   |                           ^^^^^^^^^^^^^^^ required by this bound in `accepts_trait`
 
 error[E0271]: type mismatch resolving `<impl GenericTrait<()> as GenericTrait<()>>::Associated == ()`
   --> $DIR/issue-87261.rs:91:5
@@ -184,14 +206,16 @@ error[E0271]: type mismatch resolving `<impl GenericTrait<()> as GenericTrait<()
 LL | fn returns_opaque_generic() -> impl GenericTrait<()> + 'static {
    |                                ------------------------------- the found opaque type
 ...
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(returns_opaque_generic());
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<impl GenericTrait<()> as GenericTrait<()>>::Associated`
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 help: consider constraining the associated type `<impl GenericTrait<()> as GenericTrait<()>>::Associated` to `()`
    |
 LL | fn returns_opaque_generic() -> impl GenericTrait<(), Associated = ()> + 'static {
@@ -203,14 +227,16 @@ error[E0271]: type mismatch resolving `<impl GenericTrait<()>+Foo as GenericTrai
 LL | fn returns_opaque_generic_foo() -> impl GenericTrait<()> + Foo {
    |                                    --------------------------- the found opaque type
 ...
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(returns_opaque_generic_foo());
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
    = note:    expected unit type `()`
            found associated type `<impl GenericTrait<()>+Foo as GenericTrait<()>>::Associated`
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 help: consider constraining the associated type `<impl GenericTrait<()>+Foo as GenericTrait<()>>::Associated` to `()`
    |
 LL | fn returns_opaque_generic_foo() -> impl GenericTrait<(), Associated = ()> + Foo {
@@ -222,9 +248,6 @@ error[E0271]: type mismatch resolving `<impl GenericTrait<()>+GenericTrait<u8> a
 LL | fn returns_opaque_generic_duplicate() -> impl GenericTrait<()> + GenericTrait<u8> {
    |                                          ---------------------------------------- the found opaque type
 ...
-LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
-   |                                              --------------- required by this bound in `accepts_generic_trait`
-...
 LL |     accepts_generic_trait(returns_opaque_generic_duplicate());
    |     ^^^^^^^^^^^^^^^^^^^^^ expected `()`, found associated type
    |
@@ -232,6 +255,11 @@ LL |     accepts_generic_trait(returns_opaque_generic_duplicate());
            found associated type `<impl GenericTrait<()>+GenericTrait<u8> as GenericTrait<()>>::Associated`
    = help: consider constraining the associated type `<impl GenericTrait<()>+GenericTrait<u8> as GenericTrait<()>>::Associated` to `()`
    = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: required by a bound in `accepts_generic_trait`
+  --> $DIR/issue-87261.rs:44:46
+   |
+LL | fn accepts_generic_trait<T: GenericTrait<(), Associated = ()>>(_: T) {}
+   |                                              ^^^^^^^^^^^^^^^ required by this bound in `accepts_generic_trait`
 
 error: aborting due to 14 previous errors
 

src/test/ui/associated-types/point-at-type-on-obligation-failure-2.stderr

@@ -1,35 +1,44 @@
 error[E0277]: the trait bound `bool: Bar` is not satisfied
   --> $DIR/point-at-type-on-obligation-failure-2.rs:8:5
    |
-LL |     type Assoc: Bar;
-   |                 --- required by this bound in `Foo::Assoc`
-...
 LL |     type Assoc = bool;
    |     ^^^^^^^^^^^^^^^^^^ the trait `Bar` is not implemented for `bool`
+   |
+note: required by a bound in `Foo::Assoc`
+  --> $DIR/point-at-type-on-obligation-failure-2.rs:4:17
+   |
+LL |     type Assoc: Bar;
+   |                 ^^^ required by this bound in `Foo::Assoc`
 
 error[E0277]: the trait bound `bool: Bar` is not satisfied
   --> $DIR/point-at-type-on-obligation-failure-2.rs:19:5
    |
+LL |     type Assoc = bool;
+   |     ^^^^^^^^^^^^^^^^^^ the trait `Bar` is not implemented for `bool`
+   |
+note: required by a bound in `Baz::Assoc`
+  --> $DIR/point-at-type-on-obligation-failure-2.rs:13:18
+   |
 LL |     Self::Assoc: Bar,
-   |                  --- required by this bound in `Baz::Assoc`
+   |                  ^^^ required by this bound in `Baz::Assoc`
 LL | {
 LL |     type Assoc;
    |          ----- required by a bound in this
-...
-LL |     type Assoc = bool;
-   |     ^^^^^^^^^^^^^^^^^^ the trait `Bar` is not implemented for `bool`
 
 error[E0277]: the trait bound `bool: Bar` is not satisfied
   --> $DIR/point-at-type-on-obligation-failure-2.rs:30:5
    |
+LL |     type Assoc = bool;
+   |     ^^^^^^^^^^^^^^^^^^ the trait `Bar` is not implemented for `bool`
+   |
+note: required by a bound in `Bat::Assoc`
+  --> $DIR/point-at-type-on-obligation-failure-2.rs:24:27
+   |
 LL |     <Self as Bat>::Assoc: Bar,
-   |                           --- required by this bound in `Bat::Assoc`
+   |                           ^^^ required by this bound in `Bat::Assoc`
 LL | {
 LL |     type Assoc;
    |          ----- required by a bound in this
-...
-LL |     type Assoc = bool;
-   |     ^^^^^^^^^^^^^^^^^^ the trait `Bar` is not implemented for `bool`
 
 error: aborting due to 3 previous errors
 

src/test/ui/associated-types/point-at-type-on-obligation-failure.stderr

@@ -1,11 +1,14 @@
 error[E0271]: type mismatch resolving `<Foo2 as Bar2>::Ok == ()`
   --> $DIR/point-at-type-on-obligation-failure.rs:14:5
    |
-LL |     type Sibling: Bar2<Ok=Self::Ok>;
-   |                        ----------- required by this bound in `Bar::Sibling`
-...
 LL |     type Sibling = Foo2;
    |     ^^^^^^^^^^^^^^^^^^^^ expected `()`, found `u32`
+   |
+note: required by a bound in `Bar::Sibling`
+  --> $DIR/point-at-type-on-obligation-failure.rs:3:24
+   |
+LL |     type Sibling: Bar2<Ok=Self::Ok>;
+   |                        ^^^^^^^^^^^ required by this bound in `Bar::Sibling`
 
 error: aborting due to previous error
 

src/test/ui/associated-types/trait-with-supertraits-needing-sized-self.stderr

@@ -4,11 +4,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL | trait ArithmeticOps: Add<Output=Self> + Sub<Output=Self> + Mul<Output=Self> + Div<Output=Self> {}
    |                      ^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/ops/arith.rs:LL:COL
+note: required by a bound in `Add`
+  --> $SRC_DIR/core/src/ops/arith.rs:LL:COL
    |
 LL | pub trait Add<Rhs = Self> {
-   |               --- required by this bound in `Add`
+   |               ^^^ required by this bound in `Add`
-   |
 help: consider further restricting `Self`
    |
 LL | trait ArithmeticOps: Add<Output=Self> + Sub<Output=Self> + Mul<Output=Self> + Div<Output=Self> + Sized {}

src/test/ui/async-await/async-fn-nonsend.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/async-fn-nonsend.rs:49:5
    |
-LL | fn assert_send(_: impl Send) {}
-   |                        ---- required by this bound in `assert_send`
-...
 LL |     assert_send(local_dropped_before_await());
    |     ^^^^^^^^^^^ future returned by `local_dropped_before_await` is not `Send`
    |
@@ -18,13 +15,15 @@ LL |     fut().await;
    |     ^^^^^^^^^^^ await occurs here, with `x` maybe used later
 LL | }
    | - `x` is later dropped here
+note: required by a bound in `assert_send`
+  --> $DIR/async-fn-nonsend.rs:46:24
+   |
+LL | fn assert_send(_: impl Send) {}
+   |                        ^^^^ required by this bound in `assert_send`
 
 error: future cannot be sent between threads safely
   --> $DIR/async-fn-nonsend.rs:51:5
    |
-LL | fn assert_send(_: impl Send) {}
-   |                        ---- required by this bound in `assert_send`
-...
 LL |     assert_send(non_send_temporary_in_match());
    |     ^^^^^^^^^^^ future returned by `non_send_temporary_in_match` is not `Send`
    |
@@ -39,13 +38,15 @@ LL |         Some(_) => fut().await,
 ...
 LL | }
    | - `non_send()` is later dropped here
+note: required by a bound in `assert_send`
+  --> $DIR/async-fn-nonsend.rs:46:24
+   |
+LL | fn assert_send(_: impl Send) {}
+   |                        ^^^^ required by this bound in `assert_send`
 
 error: future cannot be sent between threads safely
   --> $DIR/async-fn-nonsend.rs:53:5
    |
-LL | fn assert_send(_: impl Send) {}
-   |                        ---- required by this bound in `assert_send`
-...
 LL |     assert_send(non_sync_with_method_call());
    |     ^^^^^^^^^^^ future returned by `non_sync_with_method_call` is not `Send`
    |
@@ -61,6 +62,11 @@ LL |         fut().await;
 LL |     }
 LL | }
    | - `f` is later dropped here
+note: required by a bound in `assert_send`
+  --> $DIR/async-fn-nonsend.rs:46:24
+   |
+LL | fn assert_send(_: impl Send) {}
+   |                        ^^^^ required by this bound in `assert_send`
 
 error: aborting due to 3 previous errors
 

src/test/ui/async-await/issue-64130-1-sync.stderr

@@ -1,9 +1,6 @@
 error: future cannot be shared between threads safely
   --> $DIR/issue-64130-1-sync.rs:21:5
    |
-LL | fn is_sync<T: Sync>(t: T) { }
-   |               ---- required by this bound in `is_sync`
-...
 LL |     is_sync(bar());
    |     ^^^^^^^ future returned by `bar` is not `Sync`
    |
@@ -17,6 +14,11 @@ LL |     baz().await;
    |     ^^^^^^^^^^^ await occurs here, with `x` maybe used later
 LL | }
    | - `x` is later dropped here
+note: required by a bound in `is_sync`
+  --> $DIR/issue-64130-1-sync.rs:11:15
+   |
+LL | fn is_sync<T: Sync>(t: T) { }
+   |               ^^^^ required by this bound in `is_sync`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-64130-2-send.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-64130-2-send.rs:21:5
    |
-LL | fn is_send<T: Send>(t: T) { }
-   |               ---- required by this bound in `is_send`
-...
 LL |     is_send(bar());
    |     ^^^^^^^ future returned by `bar` is not `Send`
    |
@@ -17,6 +14,11 @@ LL |     baz().await;
    |     ^^^^^^^^^^^ await occurs here, with `x` maybe used later
 LL | }
    | - `x` is later dropped here
+note: required by a bound in `is_send`
+  --> $DIR/issue-64130-2-send.rs:11:15
+   |
+LL | fn is_send<T: Send>(t: T) { }
+   |               ^^^^ required by this bound in `is_send`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-64130-3-other.stderr

@@ -1,9 +1,6 @@
 error[E0277]: the trait bound `Foo: Qux` is not satisfied in `impl Future`
   --> $DIR/issue-64130-3-other.rs:24:5
    |
-LL | fn is_qux<T: Qux>(t: T) { }
-   |              --- required by this bound in `is_qux`
-LL | 
 LL | async fn bar() {
    |                - within this `impl Future`
 ...
@@ -19,6 +16,11 @@ LL |     baz().await;
    |     ^^^^^^^^^^^ await occurs here, with `x` maybe used later
 LL | }
    | - `x` is later dropped here
+note: required by a bound in `is_qux`
+  --> $DIR/issue-64130-3-other.rs:14:14
+   |
+LL | fn is_qux<T: Qux>(t: T) { }
+   |              ^^^ required by this bound in `is_qux`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-64130-non-send-future-diags.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-64130-non-send-future-diags.rs:21:5
    |
-LL | fn is_send<T: Send>(t: T) { }
-   |               ---- required by this bound in `is_send`
-...
 LL |     is_send(foo());
    |     ^^^^^^^ future returned by `foo` is not `Send`
    |
@@ -17,6 +14,11 @@ LL |     baz().await;
    |     ^^^^^^^^^^^ await occurs here, with `g` maybe used later
 LL | }
    | - `g` is later dropped here
+note: required by a bound in `is_send`
+  --> $DIR/issue-64130-non-send-future-diags.rs:7:15
+   |
+LL | fn is_send<T: Send>(t: T) { }
+   |               ^^^^ required by this bound in `is_send`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-67252-unnamed-future.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-67252-unnamed-future.rs:18:5
    |
-LL | fn spawn<T: Send>(_: T) {}
-   |             ---- required by this bound in `spawn`
-...
 LL |     spawn(async {
    |     ^^^^^ future created by async block is not `Send`
    |
@@ -17,6 +14,11 @@ LL |         AFuture.await;
    |         ^^^^^^^^^^^^^ await occurs here, with `_a` maybe used later
 LL |     });
    |     - `_a` is later dropped here
+note: required by a bound in `spawn`
+  --> $DIR/issue-67252-unnamed-future.rs:6:13
+   |
+LL | fn spawn<T: Send>(_: T) {}
+   |             ^^^^ required by this bound in `spawn`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-68112.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-68112.rs:34:5
    |
-LL | fn require_send(_: impl Send) {}
-   |                         ---- required by this bound in `require_send`
-...
 LL |     require_send(send_fut);
    |     ^^^^^^^^^^^^ future created by async block is not `Send`
    |
@@ -13,13 +10,15 @@ note: future is not `Send` as it awaits another future which is not `Send`
    |
 LL |         let _ = non_send_fut.await;
    |                 ^^^^^^^^^^^^ await occurs here on type `impl Future`, which is not `Send`
+note: required by a bound in `require_send`
+  --> $DIR/issue-68112.rs:11:25
+   |
+LL | fn require_send(_: impl Send) {}
+   |                         ^^^^ required by this bound in `require_send`
 
 error: future cannot be sent between threads safely
   --> $DIR/issue-68112.rs:43:5
    |
-LL | fn require_send(_: impl Send) {}
-   |                         ---- required by this bound in `require_send`
-...
 LL |     require_send(send_fut);
    |     ^^^^^^^^^^^^ future created by async block is not `Send`
    |
@@ -29,13 +28,15 @@ note: future is not `Send` as it awaits another future which is not `Send`
    |
 LL |         let _ = make_non_send_future1().await;
    |                 ^^^^^^^^^^^^^^^^^^^^^^^ await occurs here on type `impl Future`, which is not `Send`
+note: required by a bound in `require_send`
+  --> $DIR/issue-68112.rs:11:25
+   |
+LL | fn require_send(_: impl Send) {}
+   |                         ^^^^ required by this bound in `require_send`
 
 error[E0277]: `RefCell<i32>` cannot be shared between threads safely
   --> $DIR/issue-68112.rs:60:5
    |
-LL | fn require_send(_: impl Send) {}
-   |                         ---- required by this bound in `require_send`
-...
 LL |     require_send(send_fut);
    |     ^^^^^^^^^^^^ `RefCell<i32>` cannot be shared between threads safely
    |
@@ -50,6 +51,11 @@ LL |     require_send(send_fut);
    = note: required because it appears within the type `[static generator@$DIR/issue-68112.rs:55:26: 59:6]`
    = note: required because it appears within the type `from_generator::GenFuture<[static generator@$DIR/issue-68112.rs:55:26: 59:6]>`
    = note: required because it appears within the type `impl Future`
+note: required by a bound in `require_send`
+  --> $DIR/issue-68112.rs:11:25
+   |
+LL | fn require_send(_: impl Send) {}
+   |                         ^^^^ required by this bound in `require_send`
 
 error: aborting due to 3 previous errors
 

src/test/ui/async-await/issue-71137.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-71137.rs:20:3
    |
-LL | fn fake_spawn<F: Future + Send + 'static>(f: F) { }
-   |                           ---- required by this bound in `fake_spawn`
-...
 LL |   fake_spawn(wrong_mutex());
    |   ^^^^^^^^^^ future returned by `wrong_mutex` is not `Send`
    |
@@ -18,6 +15,11 @@ LL |     (async { "right"; }).await;
 LL |     *guard += 1;
 LL |   }
    |   - `mut guard` is later dropped here
+note: required by a bound in `fake_spawn`
+  --> $DIR/issue-71137.rs:6:27
+   |
+LL | fn fake_spawn<F: Future + Send + 'static>(f: F) { }
+   |                           ^^^^ required by this bound in `fake_spawn`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issue-72442.stderr

@@ -4,10 +4,11 @@ error[E0277]: the trait bound `Option<&str>: AsRef<Path>` is not satisfied
 LL |             let mut f = File::open(path.to_str())?;
    |                                    ^^^^^^^^^^^^^ the trait `AsRef<Path>` is not implemented for `Option<&str>`
    |
-  ::: $SRC_DIR/std/src/fs.rs:LL:COL
+note: required by a bound in `File::open`
+  --> $SRC_DIR/std/src/fs.rs:LL:COL
    |
 LL |     pub fn open<P: AsRef<Path>>(path: P) -> io::Result<File> {
-   |                    ----------- required by this bound in `File::open`
+   |                    ^^^^^^^^^^^ required by this bound in `File::open`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issues/issue-65436-raw-ptr-not-send.stderr

@@ -1,9 +1,6 @@
 error: future cannot be sent between threads safely
   --> $DIR/issue-65436-raw-ptr-not-send.rs:12:5
    |
-LL | fn assert_send<T: Send>(_: T) {}
-   |                   ---- required by this bound in `assert_send`
-...
 LL |     assert_send(async {
    |     ^^^^^^^^^^^ future created by async block is not `Send`
    |
@@ -25,6 +22,11 @@ help: consider moving this into a `let` binding to create a shorter lived borrow
    |
 LL |         bar(Foo(std::ptr::null())).await;
    |             ^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `assert_send`
+  --> $DIR/issue-65436-raw-ptr-not-send.rs:9:19
+   |
+LL | fn assert_send<T: Send>(_: T) {}
+   |                   ^^^^ required by this bound in `assert_send`
 
 error: aborting due to previous error
 

src/test/ui/async-await/issues/issue-67893.stderr

@@ -1,9 +1,6 @@
 error[E0277]: `MutexGuard<'_, ()>` cannot be sent between threads safely
   --> $DIR/issue-67893.rs:9:5
    |
-LL | fn g(_: impl Send) {}
-   |              ---- required by this bound in `g`
-...
 LL |     g(issue_67893::run())
    |     ^ `MutexGuard<'_, ()>` cannot be sent between threads safely
    |
@@ -18,6 +15,11 @@ LL | pub async fn run() {
    = note: required because it appears within the type `from_generator::GenFuture<[static generator@run::{closure#0}]>`
    = note: required because it appears within the type `impl Future`
    = note: required because it appears within the type `impl Future`
+note: required by a bound in `g`
+  --> $DIR/issue-67893.rs:6:14
+   |
+LL | fn g(_: impl Send) {}
+   |              ^^^^ required by this bound in `g`
 
 error: aborting due to previous error
 

src/test/ui/auto-traits/typeck-default-trait-impl-constituent-types-2.stderr

@@ -1,13 +1,15 @@
 error[E0277]: the trait bound `MyS2: MyTrait` is not satisfied in `(MyS2, MyS)`
   --> $DIR/typeck-default-trait-impl-constituent-types-2.rs:17:5
    |
-LL | fn is_mytrait<T: MyTrait>() {}
-   |                  ------- required by this bound in `is_mytrait`
-...
 LL |     is_mytrait::<(MyS2, MyS)>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^ within `(MyS2, MyS)`, the trait `MyTrait` is not implemented for `MyS2`
    |
    = note: required because it appears within the type `(MyS2, MyS)`
+note: required by a bound in `is_mytrait`
+  --> $DIR/typeck-default-trait-impl-constituent-types-2.rs:12:18
+   |
+LL | fn is_mytrait<T: MyTrait>() {}
+   |                  ^^^^^^^ required by this bound in `is_mytrait`
 
 error: aborting due to previous error
 

src/test/ui/auto-traits/typeck-default-trait-impl-constituent-types.stderr

@@ -1,11 +1,14 @@
 error[E0277]: the trait bound `MyS2: MyTrait` is not satisfied
   --> $DIR/typeck-default-trait-impl-constituent-types.rs:21:18
    |
-LL | fn is_mytrait<T: MyTrait>() {}
-   |                  ------- required by this bound in `is_mytrait`
-...
 LL |     is_mytrait::<MyS2>();
    |                  ^^^^ the trait `MyTrait` is not implemented for `MyS2`
+   |
+note: required by a bound in `is_mytrait`
+  --> $DIR/typeck-default-trait-impl-constituent-types.rs:16:18
+   |
+LL | fn is_mytrait<T: MyTrait>() {}
+   |                  ^^^^^^^ required by this bound in `is_mytrait`
 
 error: aborting due to previous error
 

src/test/ui/auto-traits/typeck-default-trait-impl-negation.stderr

@@ -1,20 +1,26 @@
 error[E0277]: the trait bound `ThisImplsUnsafeTrait: MyTrait` is not satisfied
   --> $DIR/typeck-default-trait-impl-negation.rs:22:19
    |
-LL | fn is_my_trait<T: MyTrait>() {}
-   |                   ------- required by this bound in `is_my_trait`
-...
 LL |     is_my_trait::<ThisImplsUnsafeTrait>();
    |                   ^^^^^^^^^^^^^^^^^^^^ the trait `MyTrait` is not implemented for `ThisImplsUnsafeTrait`
+   |
+note: required by a bound in `is_my_trait`
+  --> $DIR/typeck-default-trait-impl-negation.rs:17:19
+   |
+LL | fn is_my_trait<T: MyTrait>() {}
+   |                   ^^^^^^^ required by this bound in `is_my_trait`
 
 error[E0277]: the trait bound `ThisImplsTrait: MyUnsafeTrait` is not satisfied
   --> $DIR/typeck-default-trait-impl-negation.rs:25:26
    |
-LL | fn is_my_unsafe_trait<T: MyUnsafeTrait>() {}
-   |                          ------------- required by this bound in `is_my_unsafe_trait`
-...
 LL |     is_my_unsafe_trait::<ThisImplsTrait>();
    |                          ^^^^^^^^^^^^^^ the trait `MyUnsafeTrait` is not implemented for `ThisImplsTrait`
+   |
+note: required by a bound in `is_my_unsafe_trait`
+  --> $DIR/typeck-default-trait-impl-negation.rs:18:26
+   |
+LL | fn is_my_unsafe_trait<T: MyUnsafeTrait>() {}
+   |                          ^^^^^^^^^^^^^ required by this bound in `is_my_unsafe_trait`
 
 error: aborting due to 2 previous errors
 

src/test/ui/auto-traits/typeck-default-trait-impl-precedence.stderr

@@ -1,13 +1,15 @@
 error[E0277]: the trait bound `u32: Signed` is not satisfied
   --> $DIR/typeck-default-trait-impl-precedence.rs:19:5
    |
-LL | fn is_defaulted<T:Defaulted>() { }
-   |                   --------- required by this bound in `is_defaulted`
-...
 LL |     is_defaulted::<&'static u32>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Signed` is not implemented for `u32`
    |
    = note: required because of the requirements on the impl of `Defaulted` for `&'static u32`
+note: required by a bound in `is_defaulted`
+  --> $DIR/typeck-default-trait-impl-precedence.rs:12:19
+   |
+LL | fn is_defaulted<T:Defaulted>() { }
+   |                   ^^^^^^^^^ required by this bound in `is_defaulted`
 
 error: aborting due to previous error
 

src/test/ui/bound-suggestions.stderr

@@ -76,11 +76,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL |     const SIZE: usize = core::mem::size_of::<Self>();
    |                                              ^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider further restricting `Self`
    |
 LL | trait Foo<T>: Sized {
@@ -92,11 +92,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL |     const SIZE: usize = core::mem::size_of::<Self>();
    |                                              ^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider further restricting `Self`
    |
 LL | trait Bar: std::fmt::Display + Sized {
@@ -108,11 +108,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL |     const SIZE: usize = core::mem::size_of::<Self>();
    |                                              ^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider further restricting `Self`
    |
 LL | trait Baz: Sized where Self: std::fmt::Display {
@@ -124,11 +124,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL |     const SIZE: usize = core::mem::size_of::<Self>();
    |                                              ^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider further restricting `Self`
    |
 LL | trait Qux<T>: Sized where Self: std::fmt::Display {
@@ -140,11 +140,11 @@ error[E0277]: the size for values of type `Self` cannot be known at compilation
 LL |     const SIZE: usize = core::mem::size_of::<Self>();
    |                                              ^^^^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider further restricting `Self`
    |
 LL | trait Bat<T>: std::fmt::Display + Sized {

src/test/ui/builtin-superkinds/builtin-superkinds-double-superkind.stderr

@@ -1,13 +1,15 @@
 error[E0277]: `T` cannot be sent between threads safely
   --> $DIR/builtin-superkinds-double-superkind.rs:6:24
    |
-LL | trait Foo : Send+Sync { }
-   |             ---- required by this bound in `Foo`
-LL | 
 LL | impl <T: Sync+'static> Foo for (T,) { }
    |                        ^^^ `T` cannot be sent between threads safely
    |
    = note: required because it appears within the type `(T,)`
+note: required by a bound in `Foo`
+  --> $DIR/builtin-superkinds-double-superkind.rs:4:13
+   |
+LL | trait Foo : Send+Sync { }
+   |             ^^^^ required by this bound in `Foo`
 help: consider further restricting this bound
    |
 LL | impl <T: Sync+'static + std::marker::Send> Foo for (T,) { }
@@ -16,13 +18,15 @@ LL | impl <T: Sync+'static + std::marker::Send> Foo for (T,) { }
 error[E0277]: `T` cannot be shared between threads safely
   --> $DIR/builtin-superkinds-double-superkind.rs:9:16
    |
-LL | trait Foo : Send+Sync { }
-   |                  ---- required by this bound in `Foo`
-...
 LL | impl <T: Send> Foo for (T,T) { }
    |                ^^^ `T` cannot be shared between threads safely
    |
    = note: required because it appears within the type `(T, T)`
+note: required by a bound in `Foo`
+  --> $DIR/builtin-superkinds-double-superkind.rs:4:18
+   |
+LL | trait Foo : Send+Sync { }
+   |                  ^^^^ required by this bound in `Foo`
 help: consider further restricting this bound
    |
 LL | impl <T: Send + std::marker::Sync> Foo for (T,T) { }

src/test/ui/builtin-superkinds/builtin-superkinds-in-metadata.stderr

@@ -4,16 +4,16 @@ error[E0277]: `T` cannot be sent between threads safely
 LL | impl <T:Sync+'static> RequiresRequiresShareAndSend for X<T> { }
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `T` cannot be sent between threads safely
    |
-  ::: $DIR/auxiliary/trait_superkinds_in_metadata.rs:7:58
-   |
-LL | pub trait RequiresRequiresShareAndSend : RequiresShare + Send { }
-   |                                                          ---- required by this bound in `RequiresRequiresShareAndSend`
-   |
 note: required because it appears within the type `X<T>`
   --> $DIR/builtin-superkinds-in-metadata.rs:9:8
    |
 LL | struct X<T>(T);
    |        ^
+note: required by a bound in `RequiresRequiresShareAndSend`
+  --> $DIR/auxiliary/trait_superkinds_in_metadata.rs:7:58
+   |
+LL | pub trait RequiresRequiresShareAndSend : RequiresShare + Send { }
+   |                                                          ^^^^ required by this bound in `RequiresRequiresShareAndSend`
 help: consider further restricting this bound
    |
 LL | impl <T:Sync+'static + std::marker::Send> RequiresRequiresShareAndSend for X<T> { }

src/test/ui/builtin-superkinds/builtin-superkinds-simple.stderr

@@ -1,13 +1,15 @@
 error[E0277]: `Rc<i8>` cannot be sent between threads safely
   --> $DIR/builtin-superkinds-simple.rs:6:6
    |
-LL | trait Foo : Send { }
-   |             ---- required by this bound in `Foo`
-LL | 
 LL | impl Foo for std::rc::Rc<i8> { }
    |      ^^^ `Rc<i8>` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `Rc<i8>`
+note: required by a bound in `Foo`
+  --> $DIR/builtin-superkinds-simple.rs:4:13
+   |
+LL | trait Foo : Send { }
+   |             ^^^^ required by this bound in `Foo`
 
 error: aborting due to previous error
 

src/test/ui/builtin-superkinds/builtin-superkinds-typaram-not-send.stderr

@@ -1,12 +1,14 @@
 error[E0277]: `T` cannot be sent between threads safely
   --> $DIR/builtin-superkinds-typaram-not-send.rs:5:24
    |
-LL | trait Foo : Send { }
-   |             ---- required by this bound in `Foo`
-LL | 
 LL | impl <T: Sync+'static> Foo for T { }
    |                        ^^^ `T` cannot be sent between threads safely
    |
+note: required by a bound in `Foo`
+  --> $DIR/builtin-superkinds-typaram-not-send.rs:3:13
+   |
+LL | trait Foo : Send { }
+   |             ^^^^ required by this bound in `Foo`
 help: consider further restricting this bound
    |
 LL | impl <T: Sync+'static + std::marker::Send> Foo for T { }

src/test/ui/chalkify/chalk_initial_program.stderr

@@ -1,11 +1,14 @@
 error[E0277]: the trait bound `f32: Foo` is not satisfied
   --> $DIR/chalk_initial_program.rs:15:13
    |
-LL | fn gimme<F: Foo>() { }
-   |             --- required by this bound in `gimme`
-...
 LL |     gimme::<f32>();
    |             ^^^ the trait `Foo` is not implemented for `f32`
+   |
+note: required by a bound in `gimme`
+  --> $DIR/chalk_initial_program.rs:9:13
+   |
+LL | fn gimme<F: Foo>() { }
+   |             ^^^ required by this bound in `gimme`
 
 error: aborting due to previous error
 

src/test/ui/chalkify/generic_impls.stderr

@@ -1,26 +1,30 @@
 error[E0277]: the trait bound `(Option<T>, f32): Foo` is not satisfied
   --> $DIR/generic_impls.rs:12:13
    |
-LL | fn gimme<F: Foo>() { }
-   |             --- required by this bound in `gimme`
-...
 LL |     gimme::<(Option<T>, f32)>();
    |             ^^^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `(Option<T>, f32)`
    |
    = help: the following implementations were found:
              <(T, u32) as Foo>
+note: required by a bound in `gimme`
+  --> $DIR/generic_impls.rs:7:13
+   |
+LL | fn gimme<F: Foo>() { }
+   |             ^^^ required by this bound in `gimme`
 
 error[E0277]: the trait bound `(i32, f32): Foo` is not satisfied
   --> $DIR/generic_impls.rs:17:13
    |
-LL | fn gimme<F: Foo>() { }
-   |             --- required by this bound in `gimme`
-...
 LL |     gimme::<(i32, f32)>();
    |             ^^^^^^^^^^ the trait `Foo` is not implemented for `(i32, f32)`
    |
    = help: the following implementations were found:
              <(T, u32) as Foo>
+note: required by a bound in `gimme`
+  --> $DIR/generic_impls.rs:7:13
+   |
+LL | fn gimme<F: Foo>() { }
+   |             ^^^ required by this bound in `gimme`
 
 error: aborting due to 2 previous errors
 

src/test/ui/chalkify/impl_wf.stderr

@@ -1,22 +1,27 @@
 error[E0277]: the size for values of type `str` cannot be known at compilation time
   --> $DIR/impl_wf.rs:11:6
    |
-LL | trait Foo: Sized { }
-   |            ----- required by this bound in `Foo`
-...
 LL | impl Foo for str { }
    |      ^^^ doesn't have a size known at compile-time
    |
    = help: the trait `Sized` is not implemented for `str`
+note: required by a bound in `Foo`
+  --> $DIR/impl_wf.rs:3:12
+   |
+LL | trait Foo: Sized { }
+   |            ^^^^^ required by this bound in `Foo`
 
 error[E0277]: the trait bound `f32: Foo` is not satisfied
   --> $DIR/impl_wf.rs:22:6
    |
-LL | trait Baz<U: ?Sized> where U: Foo { }
-   |                               --- required by this bound in `Baz`
-...
 LL | impl Baz<f32> for f32 { }
    |      ^^^^^^^^ the trait `Foo` is not implemented for `f32`
+   |
+note: required by a bound in `Baz`
+  --> $DIR/impl_wf.rs:18:31
+   |
+LL | trait Baz<U: ?Sized> where U: Foo { }
+   |                               ^^^ required by this bound in `Baz`
 
 error: aborting due to 2 previous errors
 

src/test/ui/chalkify/impl_wf_2.stderr

@@ -1,11 +1,14 @@
 error[E0277]: the trait bound `f32: Foo` is not satisfied
   --> $DIR/impl_wf_2.rs:25:5
    |
-LL |     type Item: Foo;
-   |                --- required by this bound in `Bar::Item`
-...
 LL |     type Item = f32;
    |     ^^^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `f32`
+   |
+note: required by a bound in `Bar::Item`
+  --> $DIR/impl_wf_2.rs:8:16
+   |
+LL |     type Item: Foo;
+   |                ^^^ required by this bound in `Bar::Item`
 
 error: aborting due to previous error
 

src/test/ui/chalkify/type_inference.stderr

@@ -1,15 +1,17 @@
 error[E0277]: the trait bound `{float}: Bar` is not satisfied
   --> $DIR/type_inference.rs:27:14
    |
-LL | fn only_bar<T: Bar>(_x: T) { }
-   |                --- required by this bound in `only_bar`
-...
 LL |     only_bar(x);
    |              ^ the trait `Bar` is not implemented for `{float}`
    |
    = help: the following implementations were found:
              <i32 as Bar>
              <u32 as Bar>
+note: required by a bound in `only_bar`
+  --> $DIR/type_inference.rs:12:16
+   |
+LL | fn only_bar<T: Bar>(_x: T) { }
+   |                ^^^ required by this bound in `only_bar`
 
 error: aborting due to previous error
 

src/test/ui/closure-expected-type/expect-infer-var-appearing-twice.stderr

@@ -1,15 +1,18 @@
 error[E0631]: type mismatch in closure arguments
   --> $DIR/expect-infer-var-appearing-twice.rs:14:5
    |
-LL | fn with_closure<F, A>(_: F)
-   |    ------------ required by a bound in this
-LL |     where F: FnOnce(A, A)
-   |              ------------ required by this bound in `with_closure`
-...
 LL |     with_closure(|x: u32, y: i32| {
    |     ^^^^^^^^^^^^ ---------------- found signature of `fn(u32, i32) -> _`
    |     |
    |     expected signature of `fn(_, _) -> _`
+   |
+note: required by a bound in `with_closure`
+  --> $DIR/expect-infer-var-appearing-twice.rs:2:14
+   |
+LL | fn with_closure<F, A>(_: F)
+   |    ------------ required by a bound in this
+LL |     where F: FnOnce(A, A)
+   |              ^^^^^^^^^^^^ required by this bound in `with_closure`
 
 error: aborting due to previous error
 

src/test/ui/closures/closure-bounds-cant-promote-superkind-in-struct.stderr

@@ -1,12 +1,14 @@
 error[E0277]: `F` cannot be sent between threads safely
   --> $DIR/closure-bounds-cant-promote-superkind-in-struct.rs:5:22
    |
-LL | struct X<F> where F: FnOnce() + 'static + Send {
-   |                                           ---- required by this bound in `X`
-...
 LL | fn foo<F>(blk: F) -> X<F> where F: FnOnce() + 'static {
    |                      ^^^^ `F` cannot be sent between threads safely
    |
+note: required by a bound in `X`
+  --> $DIR/closure-bounds-cant-promote-superkind-in-struct.rs:1:43
+   |
+LL | struct X<F> where F: FnOnce() + 'static + Send {
+   |                                           ^^^^ required by this bound in `X`
 help: consider further restricting this bound
    |
 LL | fn foo<F>(blk: F) -> X<F> where F: FnOnce() + 'static + std::marker::Send {

src/test/ui/closures/closure-bounds-subtype.stderr

@@ -1,12 +1,14 @@
 error[E0277]: `F` cannot be shared between threads safely
   --> $DIR/closure-bounds-subtype.rs:13:22
    |
-LL | fn take_const_owned<F>(_: F) where F: FnOnce() + Sync + Send {
-   |                                                  ---- required by this bound in `take_const_owned`
-...
 LL |     take_const_owned(f);
    |                      ^ `F` cannot be shared between threads safely
    |
+note: required by a bound in `take_const_owned`
+  --> $DIR/closure-bounds-subtype.rs:4:50
+   |
+LL | fn take_const_owned<F>(_: F) where F: FnOnce() + Sync + Send {
+   |                                                  ^^^^ required by this bound in `take_const_owned`
 help: consider further restricting this bound
    |
 LL | fn give_owned<F>(f: F) where F: FnOnce() + Send + std::marker::Sync {

src/test/ui/closures/closure-move-sync.stderr

@@ -4,14 +4,14 @@ error[E0277]: `std::sync::mpsc::Receiver<()>` cannot be shared between threads s
 LL |     let t = thread::spawn(|| {
    |             ^^^^^^^^^^^^^ `std::sync::mpsc::Receiver<()>` cannot be shared between threads safely
    |
-  ::: $SRC_DIR/std/src/thread/mod.rs:LL:COL
-   |
-LL |     F: Send + 'static,
-   |        ---- required by this bound in `spawn`
-   |
    = help: the trait `Sync` is not implemented for `std::sync::mpsc::Receiver<()>`
    = note: required because of the requirements on the impl of `Send` for `&std::sync::mpsc::Receiver<()>`
    = note: required because it appears within the type `[closure@$DIR/closure-move-sync.rs:6:27: 9:6]`
+note: required by a bound in `spawn`
+  --> $SRC_DIR/std/src/thread/mod.rs:LL:COL
+   |
+LL |     F: Send + 'static,
+   |        ^^^^ required by this bound in `spawn`
 
 error[E0277]: `Sender<()>` cannot be shared between threads safely
   --> $DIR/closure-move-sync.rs:18:5
@@ -19,14 +19,14 @@ error[E0277]: `Sender<()>` cannot be shared between threads safely
 LL |     thread::spawn(|| tx.send(()).unwrap());
    |     ^^^^^^^^^^^^^ `Sender<()>` cannot be shared between threads safely
    |
-  ::: $SRC_DIR/std/src/thread/mod.rs:LL:COL
-   |
-LL |     F: Send + 'static,
-   |        ---- required by this bound in `spawn`
-   |
    = help: the trait `Sync` is not implemented for `Sender<()>`
    = note: required because of the requirements on the impl of `Send` for `&Sender<()>`
    = note: required because it appears within the type `[closure@$DIR/closure-move-sync.rs:18:19: 18:42]`
+note: required by a bound in `spawn`
+  --> $SRC_DIR/std/src/thread/mod.rs:LL:COL
+   |
+LL |     F: Send + 'static,
+   |        ^^^^ required by this bound in `spawn`
 
 error: aborting due to 2 previous errors
 

src/test/ui/coherence/coherence-unsafe-trait-object-impl.stderr

@@ -1,11 +1,14 @@
 error[E0277]: the trait bound `&dyn Trait: Trait` is not satisfied
   --> $DIR/coherence-unsafe-trait-object-impl.rs:15:13
    |
-LL | fn takes_t<S: Trait>(s: S) {
-   |               ----- required by this bound in `takes_t`
-...
 LL |     takes_t(t);
    |             ^ the trait `Trait` is not implemented for `&dyn Trait`
+   |
+note: required by a bound in `takes_t`
+  --> $DIR/coherence-unsafe-trait-object-impl.rs:10:15
+   |
+LL | fn takes_t<S: Trait>(s: S) {
+   |               ^^^^^ required by this bound in `takes_t`
 
 error: aborting due to previous error
 

src/test/ui/const-generics/associated-type-bound-fail.full.stderr

@@ -1,14 +1,16 @@
 error[E0277]: the trait bound `u16: Bar<N>` is not satisfied
   --> $DIR/associated-type-bound-fail.rs:13:5
    |
-LL |     type Assoc: Bar<N>;
-   |                 ------ required by this bound in `Foo::Assoc`
-...
 LL |     type Assoc = u16;
    |     ^^^^^^^^^^^^^^^^^ the trait `Bar<N>` is not implemented for `u16`
    |
    = help: the following implementations were found:
              <u16 as Bar<3_usize>>
+note: required by a bound in `Foo::Assoc`
+  --> $DIR/associated-type-bound-fail.rs:8:17
+   |
+LL |     type Assoc: Bar<N>;
+   |                 ^^^^^^ required by this bound in `Foo::Assoc`
 
 error: aborting due to previous error
 

src/test/ui/const-generics/associated-type-bound-fail.min.stderr

@@ -1,14 +1,16 @@
 error[E0277]: the trait bound `u16: Bar<N>` is not satisfied
   --> $DIR/associated-type-bound-fail.rs:13:5
    |
-LL |     type Assoc: Bar<N>;
-   |                 ------ required by this bound in `Foo::Assoc`
-...
 LL |     type Assoc = u16;
    |     ^^^^^^^^^^^^^^^^^ the trait `Bar<N>` is not implemented for `u16`
    |
    = help: the following implementations were found:
              <u16 as Bar<3_usize>>
+note: required by a bound in `Foo::Assoc`
+  --> $DIR/associated-type-bound-fail.rs:8:17
+   |
+LL |     type Assoc: Bar<N>;
+   |                 ^^^^^^ required by this bound in `Foo::Assoc`
 
 error: aborting due to previous error
 

src/test/ui/const-generics/const-argument-if-length.full.stderr

@@ -6,11 +6,11 @@ LL | pub const fn is_zst<T: ?Sized>() -> usize {
 LL |     if std::mem::size_of::<T>() == 0 {
    |                            ^ doesn't have a size known at compile-time
    |
-  ::: $SRC_DIR/core/src/mem/mod.rs:LL:COL
+note: required by a bound in `std::mem::size_of`
+  --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
    |
 LL | pub const fn size_of<T>() -> usize {
-   |                      - required by this bound in `std::mem::size_of`
+   |                      ^ required by this bound in `std::mem::size_of`
-   |
 help: consider removing the `?Sized` bound to make the type parameter `Sized`
    |
 LL - pub const fn is_zst<T: ?Sized>() -> usize {

src/test/ui/const-generics/const_evaluatable_checked/abstract-const-as-cast-3.stderr

@@ -1,9 +1,6 @@
 error: unconstrained generic constant
   --> $DIR/abstract-const-as-cast-3.rs:17:5
    |
-LL |     fn assert_impl<T: Trait>() {}
-   |                       ----- required by this bound in `use_trait_impl::assert_impl`
-...
 LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as u128 }>>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
@@ -13,6 +10,11 @@ note: required because of the requirements on the impl of `Trait` for `HasCastIn
    |
 LL | impl<const O: usize> Trait for HasCastInTraitImpl<O, { O as u128 }> {}
    |                      ^^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `use_trait_impl::assert_impl`
+  --> $DIR/abstract-const-as-cast-3.rs:14:23
+   |
+LL |     fn assert_impl<T: Trait>() {}
+   |                       ^^^^^ required by this bound in `use_trait_impl::assert_impl`
 
 error[E0308]: mismatched types
   --> $DIR/abstract-const-as-cast-3.rs:17:5
@@ -26,9 +28,6 @@ LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as u128 }>>();
 error: unconstrained generic constant
   --> $DIR/abstract-const-as-cast-3.rs:20:5
    |
-LL |     fn assert_impl<T: Trait>() {}
-   |                       ----- required by this bound in `use_trait_impl::assert_impl`
-...
 LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as _ }>>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
@@ -38,6 +37,11 @@ note: required because of the requirements on the impl of `Trait` for `HasCastIn
    |
 LL | impl<const O: usize> Trait for HasCastInTraitImpl<O, { O as u128 }> {}
    |                      ^^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `use_trait_impl::assert_impl`
+  --> $DIR/abstract-const-as-cast-3.rs:14:23
+   |
+LL |     fn assert_impl<T: Trait>() {}
+   |                       ^^^^^ required by this bound in `use_trait_impl::assert_impl`
 
 error[E0308]: mismatched types
   --> $DIR/abstract-const-as-cast-3.rs:20:5
@@ -69,9 +73,6 @@ LL |     assert_impl::<HasCastInTraitImpl<14, 13>>();
 error: unconstrained generic constant
   --> $DIR/abstract-const-as-cast-3.rs:35:5
    |
-LL |     fn assert_impl<T: Trait>() {}
-   |                       ----- required by this bound in `use_trait_impl_2::assert_impl`
-...
 LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as u128 }>>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
@@ -81,6 +82,11 @@ note: required because of the requirements on the impl of `Trait` for `HasCastIn
    |
 LL | impl<const O: usize> Trait for HasCastInTraitImpl<O, { O as u128 }> {}
    |                      ^^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `use_trait_impl_2::assert_impl`
+  --> $DIR/abstract-const-as-cast-3.rs:32:23
+   |
+LL |     fn assert_impl<T: Trait>() {}
+   |                       ^^^^^ required by this bound in `use_trait_impl_2::assert_impl`
 
 error[E0308]: mismatched types
   --> $DIR/abstract-const-as-cast-3.rs:35:5
@@ -94,9 +100,6 @@ LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as u128 }>>();
 error: unconstrained generic constant
   --> $DIR/abstract-const-as-cast-3.rs:38:5
    |
-LL |     fn assert_impl<T: Trait>() {}
-   |                       ----- required by this bound in `use_trait_impl_2::assert_impl`
-...
 LL |     assert_impl::<HasCastInTraitImpl<{ N + 1 }, { N as _ }>>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
@@ -106,6 +109,11 @@ note: required because of the requirements on the impl of `Trait` for `HasCastIn
    |
 LL | impl<const O: usize> Trait for HasCastInTraitImpl<O, { O as u128 }> {}
    |                      ^^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `use_trait_impl_2::assert_impl`
+  --> $DIR/abstract-const-as-cast-3.rs:32:23
+   |
+LL |     fn assert_impl<T: Trait>() {}
+   |                       ^^^^^ required by this bound in `use_trait_impl_2::assert_impl`
 
 error[E0308]: mismatched types
   --> $DIR/abstract-const-as-cast-3.rs:38:5

src/test/ui/const-generics/const_evaluatable_checked/cross_crate_predicate.stderr

@@ -4,12 +4,12 @@ error: unconstrained generic constant
 LL |     let _ = const_evaluatable_lib::test1::<T>();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-  ::: $DIR/auxiliary/const_evaluatable_lib.rs:6:10
+   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
+note: required by a bound in `test1`
+  --> $DIR/auxiliary/const_evaluatable_lib.rs:6:10
    |
 LL |     [u8; std::mem::size_of::<T>() - 1]: Sized,
-   |          ---------------------------- required by this bound in `test1`
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `test1`
-   |
-   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
 
 error: unconstrained generic constant
   --> $DIR/cross_crate_predicate.rs:7:13
@@ -17,12 +17,12 @@ error: unconstrained generic constant
 LL |     let _ = const_evaluatable_lib::test1::<T>();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-  ::: $DIR/auxiliary/const_evaluatable_lib.rs:4:27
+   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
+note: required by a bound in `test1`
+  --> $DIR/auxiliary/const_evaluatable_lib.rs:4:27
    |
 LL | pub fn test1<T>() -> [u8; std::mem::size_of::<T>() - 1]
-   |                           ---------------------------- required by this bound in `test1`
+   |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `test1`
-   |
-   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
 
 error: unconstrained generic constant
   --> $DIR/cross_crate_predicate.rs:7:13
@@ -30,12 +30,12 @@ error: unconstrained generic constant
 LL |     let _ = const_evaluatable_lib::test1::<T>();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-  ::: $DIR/auxiliary/const_evaluatable_lib.rs:6:10
+   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
+note: required by a bound in `test1`
+  --> $DIR/auxiliary/const_evaluatable_lib.rs:6:10
    |
 LL |     [u8; std::mem::size_of::<T>() - 1]: Sized,
-   |          ---------------------------- required by this bound in `test1`
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `test1`
-   |
-   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
 
 error: unconstrained generic constant
   --> $DIR/cross_crate_predicate.rs:7:13
@@ -43,12 +43,12 @@ error: unconstrained generic constant
 LL |     let _ = const_evaluatable_lib::test1::<T>();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-  ::: $DIR/auxiliary/const_evaluatable_lib.rs:4:27
+   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
+note: required by a bound in `test1`
+  --> $DIR/auxiliary/const_evaluatable_lib.rs:4:27
    |
 LL | pub fn test1<T>() -> [u8; std::mem::size_of::<T>() - 1]
-   |                           ---------------------------- required by this bound in `test1`
+   |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `test1`
-   |
-   = help: try adding a `where` bound using this expression: `where [(); std::mem::size_of::<T>() - 1]:`
 
 error: aborting due to 4 previous errors
 

src/test/ui/const-generics/const_evaluatable_checked/object-safety-ok-infer-err.stderr

@@ -1,11 +1,14 @@
 error[E0284]: type annotations needed: cannot satisfy `the constant `use_dyn::<{_: usize}>::{constant#0}` can be evaluated`
   --> $DIR/object-safety-ok-infer-err.rs:20:5
    |
-LL | fn use_dyn<const N: usize>(v: &dyn Foo<N>) where [u8; N + 1]: Sized {
-   |                                                       ----- required by this bound in `use_dyn`
-...
 LL |     use_dyn(&());
    |     ^^^^^^^ cannot satisfy `the constant `use_dyn::<{_: usize}>::{constant#0}` can be evaluated`
+   |
+note: required by a bound in `use_dyn`
+  --> $DIR/object-safety-ok-infer-err.rs:14:55
+   |
+LL | fn use_dyn<const N: usize>(v: &dyn Foo<N>) where [u8; N + 1]: Sized {
+   |                                                       ^^^^^ required by this bound in `use_dyn`
 
 error: aborting due to previous error
 

src/test/ui/const-generics/issues/issue-67185-2.full.stderr

@@ -37,66 +37,74 @@ LL | | }
 error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
   --> $DIR/issue-67185-2.rs:26:6
    |
-LL | trait Foo
-   |       --- required by a bound in this
-...
-LL |         <u8 as Baz>::Quaks: Bar,
-   |                             --- required by this bound in `Foo`
-...
 LL | impl Foo for FooImpl {}
    |      ^^^ the trait `Bar` is not implemented for `[u16; 3]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
+note: required by a bound in `Foo`
+  --> $DIR/issue-67185-2.rs:20:29
+   |
+LL | trait Foo
+   |       --- required by a bound in this
+...
+LL |         <u8 as Baz>::Quaks: Bar,
+   |                             ^^^ required by this bound in `Foo`
 
 error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
   --> $DIR/issue-67185-2.rs:26:6
    |
-LL | trait Foo
-   |       --- required by a bound in this
-...
-LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                                  --- required by this bound in `Foo`
-...
 LL | impl Foo for FooImpl {}
    |      ^^^ the trait `Bar` is not implemented for `[[u16; 3]; 2]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
-
+note: required by a bound in `Foo`
-error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:19:34
-  --> $DIR/issue-67185-2.rs:30:14
    |
 LL | trait Foo
    |       --- required by a bound in this
 ...
 LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                                  --- required by this bound in `Foo`
+   |                                  ^^^ required by this bound in `Foo`
-...
+
+error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:30:14
+   |
 LL | fn f(_: impl Foo) {}
    |              ^^^ the trait `Bar` is not implemented for `[[u16; 3]; 2]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
-
+note: required by a bound in `Foo`
-error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:19:34
-  --> $DIR/issue-67185-2.rs:30:14
    |
 LL | trait Foo
    |       --- required by a bound in this
 ...
-LL |         <u8 as Baz>::Quaks: Bar,
+LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                             --- required by this bound in `Foo`
+   |                                  ^^^ required by this bound in `Foo`
-...
+
+error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:30:14
+   |
 LL | fn f(_: impl Foo) {}
    |              ^^^ the trait `Bar` is not implemented for `[u16; 3]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
+note: required by a bound in `Foo`
+  --> $DIR/issue-67185-2.rs:20:29
+   |
+LL | trait Foo
+   |       --- required by a bound in this
+...
+LL |         <u8 as Baz>::Quaks: Bar,
+   |                             ^^^ required by this bound in `Foo`
 
 error: aborting due to 6 previous errors
 

src/test/ui/const-generics/issues/issue-67185-2.min.stderr

@@ -37,66 +37,74 @@ LL | | }
 error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
   --> $DIR/issue-67185-2.rs:26:6
    |
-LL | trait Foo
-   |       --- required by a bound in this
-...
-LL |         <u8 as Baz>::Quaks: Bar,
-   |                             --- required by this bound in `Foo`
-...
 LL | impl Foo for FooImpl {}
    |      ^^^ the trait `Bar` is not implemented for `[u16; 3]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
+note: required by a bound in `Foo`
+  --> $DIR/issue-67185-2.rs:20:29
+   |
+LL | trait Foo
+   |       --- required by a bound in this
+...
+LL |         <u8 as Baz>::Quaks: Bar,
+   |                             ^^^ required by this bound in `Foo`
 
 error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
   --> $DIR/issue-67185-2.rs:26:6
    |
-LL | trait Foo
-   |       --- required by a bound in this
-...
-LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                                  --- required by this bound in `Foo`
-...
 LL | impl Foo for FooImpl {}
    |      ^^^ the trait `Bar` is not implemented for `[[u16; 3]; 2]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
-
+note: required by a bound in `Foo`
-error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:19:34
-  --> $DIR/issue-67185-2.rs:30:14
    |
 LL | trait Foo
    |       --- required by a bound in this
 ...
 LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                                  --- required by this bound in `Foo`
+   |                                  ^^^ required by this bound in `Foo`
-...
+
+error[E0277]: the trait bound `[[u16; 3]; 2]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:30:14
+   |
 LL | fn f(_: impl Foo) {}
    |              ^^^ the trait `Bar` is not implemented for `[[u16; 3]; 2]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
-
+note: required by a bound in `Foo`
-error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:19:34
-  --> $DIR/issue-67185-2.rs:30:14
    |
 LL | trait Foo
    |       --- required by a bound in this
 ...
-LL |         <u8 as Baz>::Quaks: Bar,
+LL |         [<u8 as Baz>::Quaks; 2]: Bar,
-   |                             --- required by this bound in `Foo`
+   |                                  ^^^ required by this bound in `Foo`
-...
+
+error[E0277]: the trait bound `[u16; 3]: Bar` is not satisfied
+  --> $DIR/issue-67185-2.rs:30:14
+   |
 LL | fn f(_: impl Foo) {}
    |              ^^^ the trait `Bar` is not implemented for `[u16; 3]`
    |
    = help: the following implementations were found:
              <[[u16; 3]; 3] as Bar>
              <[u16; 4] as Bar>
+note: required by a bound in `Foo`
+  --> $DIR/issue-67185-2.rs:20:29
+   |
+LL | trait Foo
+   |       --- required by a bound in this
+...
+LL |         <u8 as Baz>::Quaks: Bar,
+   |                             ^^^ required by this bound in `Foo`
 
 error: aborting due to 6 previous errors
 

src/test/ui/const-generics/issues/issue-72787.min.stderr

@@ -37,24 +37,28 @@ LL |     IsLessOrEqual<{ 8 - I }, { 8 - J }>: True,
 error[E0283]: type annotations needed
   --> $DIR/issue-72787.rs:21:26
    |
-LL | pub trait True {}
-   | -------------- required by this bound in `True`
-...
 LL |     IsLessOrEqual<I, 8>: True,
    |                          ^^^^ cannot infer type for struct `IsLessOrEqual<I, 8_u32>`
    |
    = note: cannot satisfy `IsLessOrEqual<I, 8_u32>: True`
+note: required by a bound in `True`
+  --> $DIR/issue-72787.rs:7:1
+   |
+LL | pub trait True {}
+   | ^^^^^^^^^^^^^^ required by this bound in `True`
 
 error[E0283]: type annotations needed
   --> $DIR/issue-72787.rs:21:26
    |
-LL | pub trait True {}
-   | -------------- required by this bound in `True`
-...
 LL |     IsLessOrEqual<I, 8>: True,
    |                          ^^^^ cannot infer type for struct `IsLessOrEqual<I, 8_u32>`
    |
    = note: cannot satisfy `IsLessOrEqual<I, 8_u32>: True`
+note: required by a bound in `True`
+  --> $DIR/issue-72787.rs:7:1
+   |
+LL | pub trait True {}
+   | ^^^^^^^^^^^^^^ required by this bound in `True`
 
 error: aborting due to 6 previous errors
 

src/test/ui/const-generics/issues/issue-85848.stderr

@@ -3,9 +3,6 @@ error[E0277]: the trait bound `(): _Contains<&C>` is not satisfied
    |
 LL |     writes_to_specific_path(&cap);
    |     ^^^^^^^^^^^^^^^^^^^^^^^ the trait `_Contains<&C>` is not implemented for `()`
-...
-LL | fn writes_to_specific_path<C: Delegates<()>>(cap: &C) {}
-   |                               ------------- required by this bound in `writes_to_specific_path`
    |
 note: required because of the requirements on the impl of `Contains<(), true>` for `&C`
   --> $DIR/issue-85848.rs:21:12
@@ -17,15 +14,17 @@ note: required because of the requirements on the impl of `Delegates<()>` for `&
    |
 LL | impl<T, U> Delegates<U> for T where T: Contains<U, true> {}
    |            ^^^^^^^^^^^^     ^
+note: required by a bound in `writes_to_specific_path`
+  --> $DIR/issue-85848.rs:29:31
+   |
+LL | fn writes_to_specific_path<C: Delegates<()>>(cap: &C) {}
+   |                               ^^^^^^^^^^^^^ required by this bound in `writes_to_specific_path`
 
 error: unconstrained generic constant
   --> $DIR/issue-85848.rs:24:5
    |
 LL |     writes_to_specific_path(&cap);
    |     ^^^^^^^^^^^^^^^^^^^^^^^
-...
-LL | fn writes_to_specific_path<C: Delegates<()>>(cap: &C) {}
-   |                               ------------- required by this bound in `writes_to_specific_path`
    |
    = help: try adding a `where` bound using this expression: `where [(); { contains::<T, U>() }]:`
 note: required because of the requirements on the impl of `Contains<(), true>` for `&C`
@@ -38,6 +37,11 @@ note: required because of the requirements on the impl of `Delegates<()>` for `&
    |
 LL | impl<T, U> Delegates<U> for T where T: Contains<U, true> {}
    |            ^^^^^^^^^^^^     ^
+note: required by a bound in `writes_to_specific_path`
+  --> $DIR/issue-85848.rs:29:31
+   |
+LL | fn writes_to_specific_path<C: Delegates<()>>(cap: &C) {}
+   |                               ^^^^^^^^^^^^^ required by this bound in `writes_to_specific_path`
 
 error: aborting due to 2 previous errors
 

src/test/ui/const-generics/parent_generics_of_encoding_impl_trait.stderr

@@ -4,10 +4,11 @@ error[E0284]: type annotations needed: cannot satisfy `the constant `foo::{opaqu
 LL |     generics_of_parent_impl_trait::foo([()]);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot satisfy `the constant `foo::{opaque#0}::{constant#0}` can be evaluated`
    |
-  ::: $DIR/auxiliary/generics_of_parent_impl_trait.rs:6:48
+note: required by a bound in `foo`
+  --> $DIR/auxiliary/generics_of_parent_impl_trait.rs:6:48
    |
 LL | pub fn foo<const N: usize>(foo: impl Into<[(); N + 1]>) {
-   |                                                ----- required by this bound in `foo`
+   |                                                ^^^^^ required by this bound in `foo`
 
 error: aborting due to previous error
 

src/test/ui/derives/derives-span-Eq-enum-struct-variant.stderr

@@ -7,11 +7,11 @@ LL | #[derive(Eq,PartialEq)]
 LL |      x: Error
    |      ^^^^^^^^ the trait `Eq` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/cmp.rs:LL:COL
+note: required by a bound in `AssertParamIsEq`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
    |
 LL | pub struct AssertParamIsEq<T: Eq + ?Sized> {
-   |                               -- required by this bound in `AssertParamIsEq`
+   |                               ^^ required by this bound in `AssertParamIsEq`
-   |
    = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Eq-enum.stderr

@@ -7,11 +7,11 @@ LL | #[derive(Eq,PartialEq)]
 LL |      Error
    |      ^^^^^ the trait `Eq` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/cmp.rs:LL:COL
+note: required by a bound in `AssertParamIsEq`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
    |
 LL | pub struct AssertParamIsEq<T: Eq + ?Sized> {
-   |                               -- required by this bound in `AssertParamIsEq`
+   |                               ^^ required by this bound in `AssertParamIsEq`
-   |
    = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Eq-struct.stderr

@@ -7,11 +7,11 @@ LL | struct Struct {
 LL |     x: Error
    |     ^^^^^^^^ the trait `Eq` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/cmp.rs:LL:COL
+note: required by a bound in `AssertParamIsEq`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
    |
 LL | pub struct AssertParamIsEq<T: Eq + ?Sized> {
-   |                               -- required by this bound in `AssertParamIsEq`
+   |                               ^^ required by this bound in `AssertParamIsEq`
-   |
    = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Eq-tuple-struct.stderr

@@ -7,11 +7,11 @@ LL | struct Struct(
 LL |     Error
    |     ^^^^^ the trait `Eq` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/cmp.rs:LL:COL
+note: required by a bound in `AssertParamIsEq`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
    |
 LL | pub struct AssertParamIsEq<T: Eq + ?Sized> {
-   |                               -- required by this bound in `AssertParamIsEq`
+   |                               ^^ required by this bound in `AssertParamIsEq`
-   |
    = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Hash-enum-struct-variant.stderr

@@ -7,11 +7,11 @@ LL | #[derive(Hash)]
 LL |      x: Error
    |      ^^^^^^^^ the trait `Hash` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/hash/mod.rs:LL:COL
+note: required by a bound in `std::hash::Hash::hash`
+  --> $SRC_DIR/core/src/hash/mod.rs:LL:COL
    |
 LL |     fn hash<H: Hasher>(&self, state: &mut H);
-   |             - required by this bound in `std::hash::Hash::hash`
+   |             ^ required by this bound in `std::hash::Hash::hash`
-   |
    = note: this error originates in the derive macro `Hash` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Hash-enum.stderr

@@ -7,11 +7,11 @@ LL | #[derive(Hash)]
 LL |      Error
    |      ^^^^^ the trait `Hash` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/hash/mod.rs:LL:COL
+note: required by a bound in `std::hash::Hash::hash`
+  --> $SRC_DIR/core/src/hash/mod.rs:LL:COL
    |
 LL |     fn hash<H: Hasher>(&self, state: &mut H);
-   |             - required by this bound in `std::hash::Hash::hash`
+   |             ^ required by this bound in `std::hash::Hash::hash`
-   |
    = note: this error originates in the derive macro `Hash` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Hash-struct.stderr

@@ -7,11 +7,11 @@ LL | struct Struct {
 LL |     x: Error
    |     ^^^^^^^^ the trait `Hash` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/hash/mod.rs:LL:COL
+note: required by a bound in `std::hash::Hash::hash`
+  --> $SRC_DIR/core/src/hash/mod.rs:LL:COL
    |
 LL |     fn hash<H: Hasher>(&self, state: &mut H);
-   |             - required by this bound in `std::hash::Hash::hash`
+   |             ^ required by this bound in `std::hash::Hash::hash`
-   |
    = note: this error originates in the derive macro `Hash` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/derives-span-Hash-tuple-struct.stderr

@@ -7,11 +7,11 @@ LL | struct Struct(
 LL |     Error
    |     ^^^^^ the trait `Hash` is not implemented for `Error`
    |
-  ::: $SRC_DIR/core/src/hash/mod.rs:LL:COL
+note: required by a bound in `std::hash::Hash::hash`
+  --> $SRC_DIR/core/src/hash/mod.rs:LL:COL
    |
 LL |     fn hash<H: Hasher>(&self, state: &mut H);
-   |             - required by this bound in `std::hash::Hash::hash`
+   |             ^ required by this bound in `std::hash::Hash::hash`
-   |
    = note: this error originates in the derive macro `Hash` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error

src/test/ui/derives/deriving-copyclone.stderr

@@ -1,9 +1,6 @@
 error[E0277]: the trait bound `C: Copy` is not satisfied
   --> $DIR/deriving-copyclone.rs:31:13
    |
-LL | fn is_copy<T: Copy>(_: T) {}
-   |               ---- required by this bound in `is_copy`
-...
 LL |     is_copy(B { a: 1, b: C });
    |             ^^^^^^^^^^^^^^^^
    |             |
@@ -15,14 +12,16 @@ note: required because of the requirements on the impl of `Copy` for `B<C>`
    |
 LL | #[derive(Copy, Clone)]
    |          ^^^^
+note: required by a bound in `is_copy`
+  --> $DIR/deriving-copyclone.rs:18:15
+   |
+LL | fn is_copy<T: Copy>(_: T) {}
+   |               ^^^^ required by this bound in `is_copy`
    = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: the trait bound `C: Clone` is not satisfied
   --> $DIR/deriving-copyclone.rs:32:14
    |
-LL | fn is_clone<T: Clone>(_: T) {}
-   |                ----- required by this bound in `is_clone`
-...
 LL |     is_clone(B { a: 1, b: C });
    |              ^^^^^^^^^^^^^^^^
    |              |
@@ -34,14 +33,16 @@ note: required because of the requirements on the impl of `Clone` for `B<C>`
    |
 LL | #[derive(Copy, Clone)]
    |                ^^^^^
+note: required by a bound in `is_clone`
+  --> $DIR/deriving-copyclone.rs:19:16
+   |
+LL | fn is_clone<T: Clone>(_: T) {}
+   |                ^^^^^ required by this bound in `is_clone`
    = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: the trait bound `D: Copy` is not satisfied
   --> $DIR/deriving-copyclone.rs:35:13
    |
-LL | fn is_copy<T: Copy>(_: T) {}
-   |               ---- required by this bound in `is_copy`
-...
 LL |     is_copy(B { a: 1, b: D });
    |             ^^^^^^^^^^^^^^^^
    |             |
@@ -53,6 +54,11 @@ note: required because of the requirements on the impl of `Copy` for `B<D>`
    |
 LL | #[derive(Copy, Clone)]
    |          ^^^^
+note: required by a bound in `is_copy`
+  --> $DIR/deriving-copyclone.rs:18:15
+   |
+LL | fn is_copy<T: Copy>(_: T) {}
+   |               ^^^^ required by this bound in `is_copy`
    = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 3 previous errors

src/test/ui/did_you_mean/recursion_limit.stderr

@@ -1,9 +1,6 @@
 error[E0275]: overflow evaluating the requirement `K: Send`
   --> $DIR/recursion_limit.rs:34:5
    |
-LL | fn is_send<T:Send>() { }
-   |              ---- required by this bound in `is_send`
-...
 LL |     is_send::<A>();
    |     ^^^^^^^^^^^^
    |
@@ -58,6 +55,11 @@ note: required because it appears within the type `A`
    |
 LL | link! { A, B }
    |         ^
+note: required by a bound in `is_send`
+  --> $DIR/recursion_limit.rs:31:14
+   |
+LL | fn is_send<T:Send>() { }
+   |              ^^^^ required by this bound in `is_send`
 
 error: aborting due to previous error
 

src/test/ui/dst/dst-sized-trait-param.stderr

@@ -1,13 +1,15 @@
 error[E0277]: the size for values of type `[isize]` cannot be known at compilation time
   --> $DIR/dst-sized-trait-param.rs:7:6
    |
-LL | trait Foo<T> : Sized { fn take(self, x: &T) { } } // Note: T is sized
-   |           - required by this bound in `Foo`
-LL | 
 LL | impl Foo<[isize]> for usize { }
    |      ^^^^^^^^^^^^ doesn't have a size known at compile-time
    |
    = help: the trait `Sized` is not implemented for `[isize]`
+note: required by a bound in `Foo`
+  --> $DIR/dst-sized-trait-param.rs:5:11
+   |
+LL | trait Foo<T> : Sized { fn take(self, x: &T) { } } // Note: T is sized
+   |           ^ required by this bound in `Foo`
 help: consider relaxing the implicit `Sized` restriction
    |
 LL | trait Foo<T: ?Sized> : Sized { fn take(self, x: &T) { } } // Note: T is sized
@@ -16,13 +18,15 @@ LL | trait Foo<T: ?Sized> : Sized { fn take(self, x: &T) { } } // Note: T is siz
 error[E0277]: the size for values of type `[usize]` cannot be known at compilation time
   --> $DIR/dst-sized-trait-param.rs:10:6
    |
-LL | trait Foo<T> : Sized { fn take(self, x: &T) { } } // Note: T is sized
-   |                ----- required by this bound in `Foo`
-...
 LL | impl Foo<isize> for [usize] { }
    |      ^^^^^^^^^^ doesn't have a size known at compile-time
    |
    = help: the trait `Sized` is not implemented for `[usize]`
+note: required by a bound in `Foo`
+  --> $DIR/dst-sized-trait-param.rs:5:16
+   |
+LL | trait Foo<T> : Sized { fn take(self, x: &T) { } } // Note: T is sized
+   |                ^^^^^ required by this bound in `Foo`
 
 error: aborting due to 2 previous errors
 

src/test/ui/error-codes/E0271.stderr

@@ -1,11 +1,14 @@
 error[E0271]: type mismatch resolving `<i8 as Trait>::AssociatedType == u32`
   --> $DIR/E0271.rs:10:5
    |
-LL | fn foo<T>(t: T) where T: Trait<AssociatedType=u32> {
-   |                                ------------------ required by this bound in `foo`
-...
 LL |     foo(3_i8);
    |     ^^^ expected `u32`, found `&str`
+   |
+note: required by a bound in `foo`
+  --> $DIR/E0271.rs:3:32
+   |
+LL | fn foo<T>(t: T) where T: Trait<AssociatedType=u32> {
+   |                                ^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
 
 error: aborting due to previous error
 

src/test/ui/error-codes/E0275.stderr

@@ -1,9 +1,6 @@
 error[E0275]: overflow evaluating the requirement `Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<T>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>: Foo`
   --> $DIR/E0275.rs:5:33
    |
-LL | trait Foo {}
-   | --------- required by this bound in `Foo`
-...
 LL | impl<T> Foo for T where Bar<T>: Foo {}
    |                                 ^^^
    |
@@ -15,6 +12,11 @@ LL | impl<T> Foo for T where Bar<T>: Foo {}
    |         ^^^     ^
    = note: 127 redundant requirements hidden
    = note: required because of the requirements on the impl of `Foo` for `Bar<T>`
+note: required by a bound in `Foo`
+  --> $DIR/E0275.rs:1:1
+   |
+LL | trait Foo {}
+   | ^^^^^^^^^ required by this bound in `Foo`
 
 error: aborting due to previous error
 

src/test/ui/error-codes/E0277-2.stderr

@@ -1,9 +1,6 @@
 error[E0277]: `*const u8` cannot be sent between threads safely
   --> $DIR/E0277-2.rs:16:5
    |
-LL | fn is_send<T: Send>() { }
-   |               ---- required by this bound in `is_send`
-...
 LL |     is_send::<Foo>();
    |     ^^^^^^^^^^^^^^ `*const u8` cannot be sent between threads safely
    |
@@ -23,6 +20,11 @@ note: required because it appears within the type `Foo`
    |
 LL | struct Foo {
    |        ^^^
+note: required by a bound in `is_send`
+  --> $DIR/E0277-2.rs:13:15
+   |
+LL | fn is_send<T: Send>() { }
+   |               ^^^^ required by this bound in `is_send`
 
 error: aborting due to previous error
 

src/test/ui/error-codes/E0277.stderr

@@ -15,11 +15,14 @@ LL | fn f(p: &Path) { }
 error[E0277]: the trait bound `i32: Foo` is not satisfied
   --> $DIR/E0277.rs:15:15
    |
-LL | fn some_func<T: Foo>(foo: T) {
-   |                 --- required by this bound in `some_func`
-...
 LL |     some_func(5i32);
    |               ^^^^ the trait `Foo` is not implemented for `i32`
+   |
+note: required by a bound in `some_func`
+  --> $DIR/E0277.rs:7:17
+   |
+LL | fn some_func<T: Foo>(foo: T) {
+   |                 ^^^ required by this bound in `some_func`
 
 error: aborting due to 2 previous errors