Revert "Suggest using Arc on !Send/!Sync types"

This reverts commit 9de1a472b6.

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

@@ -2743,12 +2743,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             }
             ObligationCauseCode::BindingObligation(item_def_id, span)
             | ObligationCauseCode::ExprBindingObligation(item_def_id, span, ..) => {
-                if self.tcx.is_diagnostic_item(sym::Send, item_def_id)
-                    || self.tcx.lang_items().sync_trait() == Some(item_def_id)
-                {
-                    return;
-                }
-
                 let item_name = tcx.def_path_str(item_def_id);
                 let short_item_name = with_forced_trimmed_paths!(tcx.def_path_str(item_def_id));
                 let mut multispan = MultiSpan::from(span);

library/core/src/marker.rs

@@ -76,11 +76,8 @@ macro marker_impls {
 #[stable(feature = "rust1", since = "1.0.0")]
 #[cfg_attr(not(test), rustc_diagnostic_item = "Send")]
 #[rustc_on_unimplemented(
-    on(_Self = "std::rc::Rc<T, A>", note = "use `std::sync::Arc` instead of `std::rc::Rc`"),
     message = "`{Self}` cannot be sent between threads safely",
-    label = "`{Self}` cannot be sent between threads safely",
+    label = "`{Self}` cannot be sent between threads safely"
-    note = "consider using `std::sync::Arc<{Self}>`; for more information visit \
-            <https://doc.rust-lang.org/book/ch16-03-shared-state.html>"
 )]
 pub unsafe auto trait Send {
     // empty.
@@ -631,11 +628,8 @@ impl<T: ?Sized> Copy for &T {}
         any(_Self = "core::cell::RefCell<T>", _Self = "std::cell::RefCell<T>"),
         note = "if you want to do aliasing and mutation between multiple threads, use `std::sync::RwLock` instead",
     ),
-    on(_Self = "std::rc::Rc<T, A>", note = "use `std::sync::Arc` instead of `std::rc::Rc`"),
     message = "`{Self}` cannot be shared between threads safely",
-    label = "`{Self}` cannot be shared between threads safely",
+    label = "`{Self}` cannot be shared between threads safely"
-    note = "consider using `std::sync::Arc<{Self}>`; for more information visit \
-            <https://doc.rust-lang.org/book/ch16-03-shared-state.html>"
 )]
 pub unsafe auto trait Sync {
     // FIXME(estebank): once support to add notes in `rustc_on_unimplemented`

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

@@ -5,7 +5,6 @@ LL |     type C: Clone + Iterator<Item: Send + Iterator<Item: for<'a> Lam<&'a u8
    |                                    ^^^^ `<<Self as Case1>::C as Iterator>::Item` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
-   = note: consider using `std::sync::Arc<<<Self as Case1>::C as Iterator>::Item>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::C as Iterator>::Item: Send {
@@ -30,7 +29,6 @@ LL |     type C: Clone + Iterator<Item: Send + Iterator<Item: for<'a> Lam<&'a u8
    |                                                                                             ^^^^ `<<Self as Case1>::C as Iterator>::Item` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `<<Self as Case1>::C as Iterator>::Item`
-   = note: consider using `std::sync::Arc<<<Self as Case1>::C as Iterator>::Item>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 help: consider further restricting the associated type
    |
 LL | trait Case1 where <<Self as Case1>::C as Iterator>::Item: Sync {

tests/ui/associated-type-bounds/return-type-notation/basic.without.stderr

@@ -14,7 +14,6 @@ LL |     is_send(foo::<T>());
    |             ^^^^^^^^^^ future returned by `foo` is not `Send`
    |
    = help: within `impl Future<Output = Result<(), ()>>`, the trait `Send` is not implemented for `impl Future<Output = Result<(), ()>>`
-   = note: consider using `std::sync::Arc<impl Future<Output = Result<(), ()>>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as it awaits another future which is not `Send`
   --> $DIR/basic.rs:13:5
    |

tests/ui/async-await/async-await-let-else.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     is_send(foo(Some(true)));
    |             ^^^^^^^^^^^^^^^ future returned by `foo` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:11:15
    |
@@ -33,7 +32,6 @@ LL |     is_send(foo2(Some(true)));
    |     required by a bound introduced by this call
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it's used within this `async fn` body
   --> $DIR/async-await-let-else.rs:27:29
    |
@@ -66,7 +64,6 @@ LL |     is_send(foo3(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo3` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:33:29
    |
@@ -88,7 +85,6 @@ LL |     is_send(foo4(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo4` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:41:15
    |

tests/ui/async-await/async-await-let-else.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     is_send(foo(Some(true)));
    |             ^^^^^^^^^^^^^^^ future returned by `foo` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:11:15
    |
@@ -31,7 +30,6 @@ LL |     is_send(foo2(Some(true)));
    |     required by a bound introduced by this call
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it's used within this `async fn` body
   --> $DIR/async-await-let-else.rs:27:29
    |
@@ -64,7 +62,6 @@ LL |     is_send(foo3(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo3` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:33:29
    |
@@ -85,7 +82,6 @@ LL |     is_send(foo4(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo4` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:41:15
    |

tests/ui/async-await/async-await-let-else.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     is_send(foo(Some(true)));
    |             ^^^^^^^^^^^^^^^ future returned by `foo` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:11:15
    |
@@ -28,7 +27,6 @@ LL |     is_send(foo2(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo2` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:23:27
    |
@@ -51,7 +49,6 @@ LL |     is_send(foo3(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo3` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:33:29
    |
@@ -73,7 +70,6 @@ LL |     is_send(foo4(Some(true)));
    |             ^^^^^^^^^^^^^^^^ future returned by `foo4` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-await-let-else.rs:41:15
    |

tests/ui/async-await/async-fn-nonsend.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(non_send_temporary_in_match());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_send_temporary_in_match` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:36:26
    |
@@ -29,7 +28,6 @@ LL |     assert_send(non_sync_with_method_call());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
-   = note: consider using `std::sync::Arc<dyn std::fmt::Write>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:49:15
    |

tests/ui/async-await/async-fn-nonsend.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(non_send_temporary_in_match());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_send_temporary_in_match` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:36:26
    |
@@ -26,7 +25,6 @@ LL |     assert_send(non_sync_with_method_call());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
-   = note: consider using `std::sync::Arc<dyn std::fmt::Write>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:49:15
    |

tests/ui/async-await/async-fn-nonsend.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(local_dropped_before_await());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `local_dropped_before_await` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:27:11
    |
@@ -29,7 +28,6 @@ LL |     assert_send(non_send_temporary_in_match());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_send_temporary_in_match` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:36:26
    |
@@ -53,7 +51,6 @@ LL |     assert_send(non_sync_with_method_call());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
-   = note: consider using `std::sync::Arc<dyn std::fmt::Write>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:49:15
    |
@@ -78,7 +75,6 @@ LL |     assert_send(non_sync_with_method_call_panic());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call_panic` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
-   = note: consider using `std::sync::Arc<dyn std::fmt::Write>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:56:15
    |
@@ -103,7 +99,6 @@ LL |     assert_send(non_sync_with_method_call_infinite_loop());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call_infinite_loop` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
-   = note: consider using `std::sync::Arc<dyn std::fmt::Write>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:63:15
    |

tests/ui/async-await/drop-track-field-assign-nonsend.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/drop-track-field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/drop-track-field-assign-nonsend.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/drop-track-field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/drop-track-field-assign-nonsend.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/drop-track-field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/field-assign-nonsend.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/field-assign-nonsend.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/field-assign-nonsend.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     assert_send(agent.handle());
    |                 ^^^^^^^^^^^^^^ future returned by `handle` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `Rc<String>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: future is not `Send` as this value is used across an await
   --> $DIR/field-assign-nonsend.rs:23:39
    |

tests/ui/async-await/in-trait/missing-send-bound.stderr

@@ -5,7 +5,6 @@ LL |     assert_is_send(test::<T>());
    |                    ^^^^^^^^^^^ future returned by `test` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `impl Future<Output = ()>`
-   = note: consider using `std::sync::Arc<impl Future<Output = ()>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as it awaits another future which is not `Send`
   --> $DIR/missing-send-bound.rs:10:5
    |

tests/ui/async-await/issue-64130-1-sync.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     is_sync(bar());
    |             ^^^^^ future returned by `bar` is not `Sync`
    |
    = help: within `impl Future<Output = ()>`, the trait `Sync` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Sync` as this value is used across an await
   --> $DIR/issue-64130-1-sync.rs:18:11
    |

tests/ui/async-await/issue-64130-1-sync.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     is_sync(bar());
    |             ^^^^^ future returned by `bar` is not `Sync`
    |
    = help: within `impl Future<Output = ()>`, the trait `Sync` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Sync` as this value is used across an await
   --> $DIR/issue-64130-1-sync.rs:18:11
    |

tests/ui/async-await/issue-64130-1-sync.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL |     is_sync(bar());
    |             ^^^^^ future returned by `bar` is not `Sync`
    |
    = help: within `impl Future<Output = ()>`, the trait `Sync` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Sync` as this value is used across an await
   --> $DIR/issue-64130-1-sync.rs:18:11
    |

tests/ui/async-await/issue-64130-4-async-move.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL | pub fn foo() -> impl Future + Send {
    |                 ^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
    |
    = help: the trait `Sync` is not implemented for `(dyn Any + Send + 'static)`
-   = note: consider using `std::sync::Arc<(dyn Any + Send + 'static)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-64130-4-async-move.rs:27:23
    |

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

@@ -5,7 +5,6 @@ LL |     is_send(foo());
    |             ^^^^^ future returned by `foo` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `MutexGuard<'_, u32>`
-   = note: consider using `std::sync::Arc<MutexGuard<'_, u32>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-64130-non-send-future-diags.rs:17:11
    |

tests/ui/async-await/issue-67252-unnamed-future.drop_tracking.stderr

@@ -10,7 +10,6 @@ LL | |     });
    | |_____^ future created by async block is not `Send`
    |
    = help: within `[async block@$DIR/issue-67252-unnamed-future.rs:21:11: 25:6]`, the trait `Send` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-67252-unnamed-future.rs:23:17
    |

tests/ui/async-await/issue-67252-unnamed-future.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     spawn(async {
    |     ^^^^^ future created by async block is not `Send`
    |
    = help: within `[async block@$DIR/issue-67252-unnamed-future.rs:21:11: 25:6]`, the trait `Send` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-67252-unnamed-future.rs:23:17
    |

tests/ui/async-await/issue-67252-unnamed-future.no_drop_tracking.stderr

@@ -10,7 +10,6 @@ LL | |     });
    | |_____^ future created by async block is not `Send`
    |
    = help: within `[async block@$DIR/issue-67252-unnamed-future.rs:21:11: 25:6]`, the trait `Send` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-67252-unnamed-future.rs:23:17
    |

tests/ui/async-await/issue-70818.drop_tracking.stderr

@@ -4,7 +4,6 @@ error: future cannot be sent between threads safely
 LL | fn foo<T: Send, U>(ty: T, ty1: U) -> impl Future<Output = (T, U)> + Send {
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<U>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send`
   --> $DIR/issue-70818.rs:9:18
    |

tests/ui/async-await/issue-70818.drop_tracking_mir.stderr

@@ -4,7 +4,6 @@ error: future cannot be sent between threads safely
 LL | fn foo<T: Send, U>(ty: T, ty1: U) -> impl Future<Output = (T, U)> + Send {
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<U>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send`
   --> $DIR/issue-70818.rs:9:18
    |

tests/ui/async-await/issue-70818.no_drop_tracking.stderr

@@ -4,7 +4,6 @@ error: future cannot be sent between threads safely
 LL | fn foo<T: Send, U>(ty: T, ty1: U) -> impl Future<Output = (T, U)> + Send {
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<U>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send`
   --> $DIR/issue-70818.rs:9:18
    |

tests/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr

@@ -5,7 +5,6 @@ LL | fn foo(x: NotSync) -> impl Future + Send {
    |                       ^^^^^^^^^^^^^^^^^^ `*mut ()` cannot be shared between threads safely
    |
    = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `PhantomData<*mut ()>`
   --> $SRC_DIR/core/src/marker.rs:LL:COL
 note: required because it appears within the type `NotSync`

tests/ui/async-await/issue-70935-complex-spans.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL | fn foo(x: NotSync) -> impl Future + Send {
    |                       ^^^^^^^^^^^^^^^^^^ `*mut ()` cannot be shared between threads safely
    |
    = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `PhantomData<*mut ()>`
   --> $SRC_DIR/core/src/marker.rs:LL:COL
 note: required because it appears within the type `NotSync`

tests/ui/async-await/issue-70935-complex-spans.no_drop_tracking.stderr

@@ -5,7 +5,6 @@ LL | fn foo(x: NotSync) -> impl Future + Send {
    |                       ^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
    |
    = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-70935-complex-spans.rs:24:12
    |

tests/ui/async-await/issue-71137.stderr

@@ -5,7 +5,6 @@ LL |   fake_spawn(wrong_mutex());
    |              ^^^^^^^^^^^^^ future returned by `wrong_mutex` is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `MutexGuard<'_, i32>`
-   = note: consider using `std::sync::Arc<MutexGuard<'_, i32>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-71137.rs:14:26
    |

tests/ui/async-await/issue-86507.drop_tracking.stderr

@@ -8,7 +8,6 @@ LL | |                 }
 LL | |             )
    | |_____________^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
   --> $DIR/issue-86507.rs:22:29
    |

tests/ui/async-await/issue-86507.drop_tracking_mir.stderr

@@ -8,7 +8,6 @@ LL | |                 }
 LL | |             )
    | |_____________^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
   --> $DIR/issue-86507.rs:22:29
    |

tests/ui/async-await/issue-86507.no_drop_tracking.stderr

@@ -8,7 +8,6 @@ LL | |                 }
 LL | |             )
    | |_____________^ future created by async block is not `Send`
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
   --> $DIR/issue-86507.rs:22:29
    |

tests/ui/async-await/issues/issue-65436-raw-ptr-not-send.no_drop_tracking.stderr

@@ -9,7 +9,6 @@ LL | |     })
    | |_____^ future created by async block is not `Send`
    |
    = help: within `[async block@$DIR/issue-65436-raw-ptr-not-send.rs:17:17: 20:6]`, the trait `Send` is not implemented for `*const u8`
-   = note: consider using `std::sync::Arc<*const u8>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/issue-65436-raw-ptr-not-send.rs:19:36
    |

tests/ui/async-await/issues/issue-67893.stderr

@@ -5,7 +5,6 @@ LL |     g(issue_67893::run())
    |       ^^^^^^^^^^^^^^^^^^ future is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `MutexGuard<'_, ()>`
-   = note: consider using `std::sync::Arc<MutexGuard<'_, ()>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: future is not `Send` as this value is used across an await
   --> $DIR/auxiliary/issue_67893.rs:12:27
    |

tests/ui/async-await/partial-drop-partial-reinit.drop_tracking.stderr

@@ -10,11 +10,10 @@ LL | async fn foo() {
    |                - within this `impl Future<Output = ()>`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required because it appears within the type `(NotSend,)`
    = note: required because it captures the following types: `ResumeTy`, `(NotSend,)`, `()`, `impl Future<Output = ()>`
 note: required because it's used within this `async fn` body
-  --> $DIR/partial-drop-partial-reinit.rs:32:16
+  --> $DIR/partial-drop-partial-reinit.rs:31:16
    |
 LL |   async fn foo() {
    |  ________________^
@@ -26,7 +25,7 @@ LL | |     bar().await;
 LL | | }
    | |_^
 note: required by a bound in `gimme_send`
-  --> $DIR/partial-drop-partial-reinit.rs:18:18
+  --> $DIR/partial-drop-partial-reinit.rs:17:18
    |
 LL | fn gimme_send<T: Send>(t: T) {
    |                  ^^^^ required by this bound in `gimme_send`

tests/ui/async-await/partial-drop-partial-reinit.no_drop_tracking.stderr

@@ -10,11 +10,10 @@ LL | async fn foo() {
    |                - within this `impl Future<Output = ()>`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required because it appears within the type `(NotSend,)`
    = note: required because it captures the following types: `ResumeTy`, `(NotSend,)`, `impl Future<Output = ()>`, `()`
 note: required because it's used within this `async fn` body
-  --> $DIR/partial-drop-partial-reinit.rs:32:16
+  --> $DIR/partial-drop-partial-reinit.rs:31:16
    |
 LL |   async fn foo() {
    |  ________________^
@@ -26,7 +25,7 @@ LL | |     bar().await;
 LL | | }
    | |_^
 note: required by a bound in `gimme_send`
-  --> $DIR/partial-drop-partial-reinit.rs:18:18
+  --> $DIR/partial-drop-partial-reinit.rs:17:18
    |
 LL | fn gimme_send<T: Send>(t: T) {
    |                  ^^^^ required by this bound in `gimme_send`

tests/ui/async-await/partial-drop-partial-reinit.rs

@@ -12,7 +12,6 @@ fn main() {
     //~| NOTE bound introduced by
     //~| NOTE appears within the type
     //~| NOTE captures the following types
-    //~| NOTE consider using `std::sync::Arc<NotSend>`
 }
 
 fn gimme_send<T: Send>(t: T) {

tests/ui/auto-traits/issue-83857-ub.stderr

@@ -5,7 +5,6 @@ LL | fn generic<T, U>(v: Foo<T, U>, f: fn(<Foo<T, U> as WithAssoc>::Output) -> i
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `Foo<T, U>` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `Foo<T, U>`
-   = note: consider using `std::sync::Arc<Foo<T, U>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required for `Foo<T, U>` to implement `WithAssoc`
   --> $DIR/issue-83857-ub.rs:15:15
    |

tests/ui/builtin-superkinds/builtin-superkinds-double-superkind.stderr

@@ -4,7 +4,6 @@ error[E0277]: `T` cannot be sent between threads safely
 LL | impl <T: Sync+'static> Foo for (T,) { }
    |                                ^^^^ `T` cannot be sent between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required because it appears within the type `(T,)`
 note: required by a bound in `Foo`
   --> $DIR/builtin-superkinds-double-superkind.rs:4:13
@@ -22,7 +21,6 @@ error[E0277]: `T` cannot be shared between threads safely
 LL | impl <T: Send> Foo for (T,T) { }
    |                        ^^^^^ `T` cannot be shared between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = 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

tests/ui/builtin-superkinds/builtin-superkinds-in-metadata.stderr

@@ -4,7 +4,6 @@ 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
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `X<T>`
   --> $DIR/builtin-superkinds-in-metadata.rs:9:8
    |

tests/ui/builtin-superkinds/builtin-superkinds-simple.stderr

@@ -5,7 +5,6 @@ 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: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required by a bound in `Foo`
   --> $DIR/builtin-superkinds-simple.rs:4:13
    |

tests/ui/builtin-superkinds/builtin-superkinds-typaram-not-send.stderr

@@ -4,7 +4,6 @@ error[E0277]: `T` cannot be sent between threads safely
 LL | impl <T: Sync+'static> Foo for T { }
    |                                ^ `T` cannot be sent between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `Foo`
   --> $DIR/builtin-superkinds-typaram-not-send.rs:3:13
    |

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

@@ -4,7 +4,6 @@ error[E0277]: `F` cannot be sent between threads safely
 LL | fn foo<F>(blk: F) -> X<F> where F: FnOnce() + 'static {
    |                      ^^^^ `F` cannot be sent between threads safely
    |
-   = note: consider using `std::sync::Arc<F>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `X`
   --> $DIR/closure-bounds-cant-promote-superkind-in-struct.rs:1:43
    |

tests/ui/closures/closure-bounds-subtype.stderr

@@ -6,7 +6,6 @@ LL |     take_const_owned(f);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<F>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `take_const_owned`
   --> $DIR/closure-bounds-subtype.rs:4:50
    |

tests/ui/closures/closure-move-sync.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ `std::sync::mpsc::Receiver<()>` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `std::sync::mpsc::Receiver<()>`
-   = note: consider using `std::sync::Arc<std::sync::mpsc::Receiver<()>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `&std::sync::mpsc::Receiver<()>` to implement `Send`
 note: required because it's used within this closure
   --> $DIR/closure-move-sync.rs:6:27

tests/ui/error-codes/E0277-2.stderr

@@ -5,7 +5,6 @@ LL |     is_send::<Foo>();
    |               ^^^ `*const u8` cannot be sent between threads safely
    |
    = help: within `Foo`, the trait `Send` is not implemented for `*const u8`
-   = note: consider using `std::sync::Arc<*const u8>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Baz`
   --> $DIR/E0277-2.rs:9:8
    |

tests/ui/extern/extern-type-diag-not-similar.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<Foo>()
    |                   ^^^ `Foo` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_send`
   --> $DIR/extern-type-diag-not-similar.rs:17:19
    |

tests/ui/extern/extern-types-not-sync-send.stderr

@@ -5,7 +5,6 @@ LL |     assert_sync::<A>();
    |                   ^ `A` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `A`
-   = note: consider using `std::sync::Arc<A>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_sync`
   --> $DIR/extern-types-not-sync-send.rs:9:28
    |
@@ -19,7 +18,6 @@ LL |     assert_send::<A>();
    |                   ^ `A` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `A`
-   = note: consider using `std::sync::Arc<A>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_send`
   --> $DIR/extern-types-not-sync-send.rs:10:28
    |

tests/ui/fmt/send-sync.stderr

@@ -7,7 +7,6 @@ LL |     send(format_args!("{:?}", c));
    |     required by a bound introduced by this call
    |
    = help: within `[core::fmt::rt::Argument<'_>]`, the trait `Sync` is not implemented for `core::fmt::rt::Opaque`
-   = note: consider using `std::sync::Arc<core::fmt::rt::Opaque>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required because it appears within the type `&core::fmt::rt::Opaque`
 note: required because it appears within the type `Argument<'_>`
   --> $SRC_DIR/core/src/fmt/rt.rs:LL:COL
@@ -30,7 +29,6 @@ LL |     sync(format_args!("{:?}", c));
    |     required by a bound introduced by this call
    |
    = help: within `Arguments<'_>`, the trait `Sync` is not implemented for `core::fmt::rt::Opaque`
-   = note: consider using `std::sync::Arc<core::fmt::rt::Opaque>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required because it appears within the type `&core::fmt::rt::Opaque`
 note: required because it appears within the type `Argument<'_>`
   --> $SRC_DIR/core/src/fmt/rt.rs:LL:COL

tests/ui/generator/drop-tracking-parent-expression.drop_tracking.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -57,7 +56,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -100,7 +98,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |

tests/ui/generator/drop-tracking-parent-expression.drop_tracking_mir.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -55,7 +54,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -96,7 +94,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |

tests/ui/generator/drop-tracking-parent-expression.no_drop_tracking.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `copy::Client`
-   = note: consider using `std::sync::Arc<copy::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -57,7 +56,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `copy::Client`
-   = note: consider using `std::sync::Arc<copy::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:38:22
    |
@@ -99,7 +97,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -142,7 +139,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:38:22
    |
@@ -184,7 +180,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -227,7 +222,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:38:22
    |
@@ -269,7 +263,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:25:22
    |
@@ -312,7 +305,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/drop-tracking-parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-tracking-parent-expression.rs:38:22
    |

tests/ui/generator/drop-yield-twice.stderr

@@ -11,7 +11,6 @@ LL | |     })
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/drop-yield-twice.rs:7:17: 7:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/drop-yield-twice.rs:9:9
    |

tests/ui/generator/issue-57017.no_drop_tracking.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: the trait `Sync` is not implemented for `copy::unsync::Client`
-   = note: consider using `std::sync::Arc<copy::unsync::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:30:28
    |
@@ -56,7 +55,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/issue-57017.rs:41:21: 41:28]`, the trait `Send` is not implemented for `copy::unsend::Client`
-   = note: consider using `std::sync::Arc<copy::unsend::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:42:28
    |
@@ -98,7 +96,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: the trait `Sync` is not implemented for `derived_drop::unsync::Client`
-   = note: consider using `std::sync::Arc<derived_drop::unsync::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:30:28
    |
@@ -140,7 +137,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/issue-57017.rs:41:21: 41:28]`, the trait `Send` is not implemented for `derived_drop::unsend::Client`
-   = note: consider using `std::sync::Arc<derived_drop::unsend::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:42:28
    |
@@ -182,7 +178,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: the trait `Sync` is not implemented for `significant_drop::unsync::Client`
-   = note: consider using `std::sync::Arc<significant_drop::unsync::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:30:28
    |
@@ -224,7 +219,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/issue-57017.rs:41:21: 41:28]`, the trait `Send` is not implemented for `significant_drop::unsend::Client`
-   = note: consider using `std::sync::Arc<significant_drop::unsend::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57017.rs:42:28
    |

tests/ui/generator/issue-57478.no_drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     })
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/issue-57478.rs:13:17: 13:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/issue-57478.rs:17:9
    |

tests/ui/generator/not-send-sync.drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Sync`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:17:17: 17:19]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/not-send-sync.rs:20:9
    |
@@ -41,7 +40,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:24:17: 24:19]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/not-send-sync.rs:27:9
    |

tests/ui/generator/not-send-sync.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     assert_sync(|| {
    |     ^^^^^^^^^^^ generator is not `Sync`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:17:17: 17:19]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/not-send-sync.rs:20:9
    |
@@ -26,7 +25,6 @@ LL |     assert_send(|| {
    |     ^^^^^^^^^^^ generator is not `Send`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:24:17: 24:19]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/not-send-sync.rs:27:9
    |

tests/ui/generator/not-send-sync.no_drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Sync`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:17:17: 17:19]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/not-send-sync.rs:20:9
    |
@@ -41,7 +40,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/not-send-sync.rs:24:17: 24:19]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/not-send-sync.rs:27:9
    |

tests/ui/generator/parent-expression.drop_tracking.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -57,7 +56,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -100,7 +98,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |

tests/ui/generator/parent-expression.drop_tracking_mir.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -55,7 +54,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -96,7 +94,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |

tests/ui/generator/parent-expression.no_drop_tracking.stderr

@@ -14,7 +14,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `copy::Client`
-   = note: consider using `std::sync::Arc<copy::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -57,7 +56,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `copy::Client`
-   = note: consider using `std::sync::Arc<copy::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:38:22
    |
@@ -99,7 +97,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -142,7 +139,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `derived_drop::Client`
-   = note: consider using `std::sync::Arc<derived_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:38:22
    |
@@ -184,7 +180,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -227,7 +222,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `significant_drop::Client`
-   = note: consider using `std::sync::Arc<significant_drop::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:38:22
    |
@@ -269,7 +263,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:21:21: 21:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:25:22
    |
@@ -312,7 +305,6 @@ LL | |     );
    | |_____- in this macro invocation
    |
    = help: within `[generator@$DIR/parent-expression.rs:37:21: 37:28]`, the trait `Send` is not implemented for `insignificant_dtor::Client`
-   = note: consider using `std::sync::Arc<insignificant_dtor::Client>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/parent-expression.rs:38:22
    |

tests/ui/generator/partial-drop.drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/partial-drop.rs:17:17: 17:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/partial-drop.rs:21:9
    |
@@ -42,7 +41,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/partial-drop.rs:24:17: 24:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/partial-drop.rs:29:9
    |

tests/ui/generator/partial-drop.no_drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/partial-drop.rs:17:17: 17:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/partial-drop.rs:21:9
    |
@@ -42,7 +41,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[generator@$DIR/partial-drop.rs:24:17: 24:19]`, the trait `Send` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/partial-drop.rs:29:9
    |

tests/ui/generator/print/generator-print-verbose-2.drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Sync`
    |
    = help: within `[main::{closure#0} upvar_tys=() {NotSync, ()}]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:23:9
    |
@@ -41,7 +40,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[main::{closure#1} upvar_tys=() {NotSend, ()}]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:30:9
    |

tests/ui/generator/print/generator-print-verbose-2.drop_tracking_mir.stderr

@@ -5,7 +5,6 @@ LL |     assert_sync(|| {
    |     ^^^^^^^^^^^ generator is not `Sync`
    |
    = help: within `[main::{closure#0} upvar_tys=() [main::{closure#0}]]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:23:9
    |
@@ -26,7 +25,6 @@ LL |     assert_send(|| {
    |     ^^^^^^^^^^^ generator is not `Send`
    |
    = help: within `[main::{closure#1} upvar_tys=() [main::{closure#1}]]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:30:9
    |

tests/ui/generator/print/generator-print-verbose-2.no_drop_tracking.stderr

@@ -11,7 +11,6 @@ LL | |     });
    | |_____^ generator is not `Sync`
    |
    = help: within `[main::{closure#0} upvar_tys=() {NotSync, ()}]`, the trait `Sync` is not implemented for `NotSync`
-   = note: consider using `std::sync::Arc<NotSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Sync` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:23:9
    |
@@ -41,7 +40,6 @@ LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: within `[main::{closure#1} upvar_tys=() {NotSend, ()}]`, the trait `Send` is not implemented for `NotSend`
-   = note: consider using `std::sync::Arc<NotSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: generator is not `Send` as this value is used across a yield
   --> $DIR/generator-print-verbose-2.rs:30:9
    |

tests/ui/generator/ref-upvar-not-send.rs

@@ -15,7 +15,6 @@ fn main() {
     assert_send(move || {
         //~^ ERROR generator cannot be sent between threads safely
         //~| NOTE generator is not `Send`
-        //~| NOTE consider using `std::sync::Arc
         yield;
         let _x = x;
     });
@@ -24,7 +23,6 @@ fn main() {
     assert_send(move || {
         //~^ ERROR generator cannot be sent between threads safely
         //~| NOTE generator is not `Send`
-        //~| NOTE consider using `std::sync::Arc
         yield;
         let _y = y;
     });

tests/ui/generator/ref-upvar-not-send.stderr

@@ -5,16 +5,14 @@ LL |       assert_send(move || {
    |  _________________^
 LL | |
 LL | |
-LL | |
 LL | |         yield;
 LL | |         let _x = x;
 LL | |     });
    | |_____^ generator is not `Send`
    |
    = help: the trait `Sync` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
-  --> $DIR/ref-upvar-not-send.rs:20:18
+  --> $DIR/ref-upvar-not-send.rs:19:18
    |
 LL |         let _x = x;
    |                  ^ has type `&*mut ()` which is not `Send`, because `*mut ()` is not `Sync`
@@ -25,22 +23,20 @@ LL | fn assert_send<T: Send>(_: T) {}
    |                   ^^^^ required by this bound in `assert_send`
 
 error: generator cannot be sent between threads safely
-  --> $DIR/ref-upvar-not-send.rs:24:17
+  --> $DIR/ref-upvar-not-send.rs:23:17
    |
 LL |       assert_send(move || {
    |  _________________^
 LL | |
 LL | |
-LL | |
 LL | |         yield;
 LL | |         let _y = y;
 LL | |     });
    | |_____^ generator is not `Send`
    |
-   = help: within `[generator@$DIR/ref-upvar-not-send.rs:24:17: 24:24]`, the trait `Send` is not implemented for `*mut ()`
+   = help: within `[generator@$DIR/ref-upvar-not-send.rs:23:17: 23:24]`, the trait `Send` is not implemented for `*mut ()`
-   = note: consider using `std::sync::Arc<*mut ()>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: captured value is not `Send` because `&mut` references cannot be sent unless their referent is `Send`
-  --> $DIR/ref-upvar-not-send.rs:29:18
+  --> $DIR/ref-upvar-not-send.rs:27:18
    |
 LL |         let _y = y;
    |                  ^ has type `&mut *mut ()` which is not `Send`, because `*mut ()` is not `Send`

tests/ui/impl-trait/auto-trait-leak2.rs

@@ -21,13 +21,11 @@ fn main() {
     //~^ ERROR `Rc<Cell<i32>>` cannot be sent between threads safely
     //~| NOTE `Rc<Cell<i32>>` cannot be sent between threads safely
     //~| NOTE required by a bound
-    //~| NOTE use `std::sync::Arc` instead
 
     send(after());
     //~^ ERROR `Rc<Cell<i32>>` cannot be sent between threads safely
     //~| NOTE `Rc<Cell<i32>>` cannot be sent between threads safely
     //~| NOTE required by a bound
-    //~| NOTE use `std::sync::Arc` instead
 }
 
 // Deferred path, main has to wait until typeck finishes,

tests/ui/impl-trait/auto-trait-leak2.stderr

@@ -10,7 +10,6 @@ LL |     send(before());
    |     required by a bound introduced by this call
    |
    = help: within `impl Fn(i32)`, the trait `Send` is not implemented for `Rc<Cell<i32>>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it's used within this closure
   --> $DIR/auto-trait-leak2.rs:10:5
    |
@@ -28,7 +27,7 @@ LL | fn send<T: Send>(_: T) {}
    |            ^^^^ required by this bound in `send`
 
 error[E0277]: `Rc<Cell<i32>>` cannot be sent between threads safely
-  --> $DIR/auto-trait-leak2.rs:26:10
+  --> $DIR/auto-trait-leak2.rs:25:10
    |
 LL |     send(after());
    |     ---- ^^^^^^^ `Rc<Cell<i32>>` cannot be sent between threads safely
@@ -39,14 +38,13 @@ LL | fn after() -> impl Fn(i32) {
    |               ------------ within this `impl Fn(i32)`
    |
    = help: within `impl Fn(i32)`, the trait `Send` is not implemented for `Rc<Cell<i32>>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it's used within this closure
-  --> $DIR/auto-trait-leak2.rs:40:5
+  --> $DIR/auto-trait-leak2.rs:38:5
    |
 LL |     move |x| p.set(x)
    |     ^^^^^^^^
 note: required because it appears within the type `impl Fn(i32)`
-  --> $DIR/auto-trait-leak2.rs:35:15
+  --> $DIR/auto-trait-leak2.rs:33:15
    |
 LL | fn after() -> impl Fn(i32) {
    |               ^^^^^^^^^^^^

tests/ui/impl-trait/in-trait/check-wf-on-non-defaulted-rpitit.stderr

@@ -5,7 +5,6 @@ LL |     fn bar() -> Wrapper<impl Sized>;
    |                 ^^^^^^^^^^^^^^^^^^^ `impl Sized` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `impl Sized`
-   = note: consider using `std::sync::Arc<impl Sized>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `Wrapper`
   --> $DIR/check-wf-on-non-defaulted-rpitit.rs:3:19
    |

tests/ui/issues/issue-21763.stderr

@@ -5,7 +5,6 @@ LL |     foo::<HashMap<Rc<()>, Rc<()>>>();
    |           ^^^^^^^^^^^^^^^^^^^^^^^ `Rc<()>` cannot be sent between threads safely
    |
    = help: within `(Rc<()>, Rc<()>)`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
    = note: required because it appears within the type `(Rc<()>, Rc<()>)`
    = note: required for `hashbrown::raw::RawTable<(Rc<()>, Rc<()>)>` to implement `Send`
 note: required because it appears within the type `HashMap<Rc<()>, Rc<()>, RandomState>`

tests/ui/issues/issue-24446.stderr

@@ -13,7 +13,6 @@ LL |     static foo: dyn Fn() -> u32 = || -> u32 {
    |                 ^^^^^^^^^^^^^^^ `(dyn Fn() -> u32 + 'static)` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `(dyn Fn() -> u32 + 'static)`
-   = note: consider using `std::sync::Arc<(dyn Fn() -> u32 + 'static)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: shared static variables must have a type that implements `Sync`
 
 error: aborting due to 2 previous errors

tests/ui/issues/issue-40827.stderr

@@ -7,7 +7,6 @@ LL |     f(Foo(Arc::new(Bar::B(None))));
    |     required by a bound introduced by this call
    |
    = help: within `Bar`, the trait `Sync` is not implemented for `Rc<Foo>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it appears within the type `Bar`
   --> $DIR/issue-40827.rs:6:6
    |
@@ -34,7 +33,6 @@ LL |     f(Foo(Arc::new(Bar::B(None))));
    |     required by a bound introduced by this call
    |
    = help: within `Bar`, the trait `Send` is not implemented for `Rc<Foo>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it appears within the type `Bar`
   --> $DIR/issue-40827.rs:6:6
    |

tests/ui/kindck/kindck-impl-type-params.stderr

@@ -4,7 +4,6 @@ error[E0277]: `T` cannot be sent between threads safely
 LL |     let a = &t as &dyn Gettable<T>;
    |             ^^ `T` cannot be sent between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required for `S<T>` to implement `Gettable<T>`
   --> $DIR/kindck-impl-type-params.rs:12:32
    |
@@ -43,7 +42,6 @@ error[E0277]: `T` cannot be sent between threads safely
 LL |     let a: &dyn Gettable<T> = &t;
    |                               ^^ `T` cannot be sent between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required for `S<T>` to implement `Gettable<T>`
   --> $DIR/kindck-impl-type-params.rs:12:32
    |

tests/ui/kindck/kindck-nonsendable-1.stderr

@@ -9,7 +9,6 @@ LL |     bar(move|| foo(x));
    |     required by a bound introduced by this call
    |
    = help: within `[closure@$DIR/kindck-nonsendable-1.rs:9:9: 9:15]`, the trait `Send` is not implemented for `Rc<usize>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it's used within this closure
   --> $DIR/kindck-nonsendable-1.rs:9:9
    |

tests/ui/kindck/kindck-send-object.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<&'static (dyn Dummy + 'static)>();
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `(dyn Dummy + 'static)` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`
-   = note: consider using `std::sync::Arc<(dyn Dummy + 'static)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object.rs:5:18
@@ -20,7 +19,6 @@ LL |     assert_send::<Box<dyn Dummy>>();
    |                   ^^^^^^^^^^^^^^ `dyn Dummy` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `dyn Dummy`
-   = note: consider using `std::sync::Arc<dyn Dummy>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `Unique<dyn Dummy>` to implement `Send`
 note: required because it appears within the type `Box<dyn Dummy>`
   --> $SRC_DIR/alloc/src/boxed.rs:LL:COL

tests/ui/kindck/kindck-send-object1.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<&'a dyn Dummy>();
    |                   ^^^^^^^^^^^^^ `(dyn Dummy + 'a)` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `(dyn Dummy + 'a)`
-   = note: consider using `std::sync::Arc<(dyn Dummy + 'a)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `&'a (dyn Dummy + 'a)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object1.rs:5:18
@@ -20,7 +19,6 @@ LL |     assert_send::<Box<dyn Dummy + 'a>>();
    |                   ^^^^^^^^^^^^^^^^^^^ `(dyn Dummy + 'a)` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `(dyn Dummy + 'a)`
-   = note: consider using `std::sync::Arc<(dyn Dummy + 'a)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `Unique<(dyn Dummy + 'a)>` to implement `Send`
 note: required because it appears within the type `Box<dyn Dummy>`
   --> $SRC_DIR/alloc/src/boxed.rs:LL:COL

tests/ui/kindck/kindck-send-object2.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<&'static dyn Dummy>();
    |                   ^^^^^^^^^^^^^^^^^^ `(dyn Dummy + 'static)` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`
-   = note: consider using `std::sync::Arc<(dyn Dummy + 'static)>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object2.rs:3:18
@@ -20,7 +19,6 @@ LL |     assert_send::<Box<dyn Dummy>>();
    |                   ^^^^^^^^^^^^^^ `dyn Dummy` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `dyn Dummy`
-   = note: consider using `std::sync::Arc<dyn Dummy>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `Unique<dyn Dummy>` to implement `Send`
 note: required because it appears within the type `Box<dyn Dummy>`
   --> $SRC_DIR/alloc/src/boxed.rs:LL:COL

tests/ui/kindck/kindck-send-owned.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<Box<*mut u8>>();
    |                   ^^^^^^^^^^^^ `*mut u8` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `*mut u8`
-   = note: consider using `std::sync::Arc<*mut u8>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: required for `Unique<*mut u8>` to implement `Send`
 note: required because it appears within the type `Box<*mut u8>`
   --> $SRC_DIR/alloc/src/boxed.rs:LL:COL

tests/ui/kindck/kindck-send-unsafe.stderr

@@ -5,7 +5,6 @@ LL |     assert_send::<*mut isize>();
    |                   ^^^^^^^^^^ `*mut isize` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `*mut isize`
-   = note: consider using `std::sync::Arc<*mut isize>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-unsafe.rs:3:19
    |
@@ -19,7 +18,6 @@ LL |     assert_send::<*mut &'a isize>();
    |                   ^^^^^^^^^^^^^^ `*mut &'a isize` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `*mut &'a isize`
-   = note: consider using `std::sync::Arc<*mut &'a isize>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-unsafe.rs:3:19
    |

tests/ui/mut/mutable-enum-indirect.stderr

@@ -7,7 +7,6 @@ LL |     bar(&x);
    |     required by a bound introduced by this call
    |
    = help: within `&Foo`, the trait `Sync` is not implemented for `NoSync`
-   = note: consider using `std::sync::Arc<NoSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Foo`
   --> $DIR/mutable-enum-indirect.rs:11:6
    |

tests/ui/no-send-res-ports.stderr

@@ -14,7 +14,6 @@ LL | |     });
    | |_____^ `Rc<()>` cannot be sent between threads safely
    |
    = help: within `[closure@$DIR/no-send-res-ports.rs:25:19: 25:25]`, the trait `Send` is not implemented for `Rc<()>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required because it appears within the type `Port<()>`
   --> $DIR/no-send-res-ports.rs:5:8
    |

tests/ui/no_send-enum.stderr

@@ -7,7 +7,6 @@ LL |     bar(x);
    |     required by a bound introduced by this call
    |
    = help: within `Foo`, the trait `Send` is not implemented for `NoSend`
-   = note: consider using `std::sync::Arc<NoSend>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Foo`
   --> $DIR/no_send-enum.rs:8:6
    |

tests/ui/no_send-rc.stderr

@@ -7,7 +7,6 @@ LL |     bar(x);
    |     required by a bound introduced by this call
    |
    = help: the trait `Send` is not implemented for `Rc<{integer}>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required by a bound in `bar`
   --> $DIR/no_send-rc.rs:3:11
    |

tests/ui/no_share-enum.stderr

@@ -7,7 +7,6 @@ LL |     bar(x);
    |     required by a bound introduced by this call
    |
    = help: within `Foo`, the trait `Sync` is not implemented for `NoSync`
-   = note: consider using `std::sync::Arc<NoSync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Foo`
   --> $DIR/no_share-enum.rs:8:6
    |

tests/ui/no_share-struct.stderr

@@ -7,7 +7,6 @@ LL |     bar(x);
    |     required by a bound introduced by this call
    |
    = help: the trait `Sync` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `bar`
   --> $DIR/no_share-struct.rs:8:11
    |

tests/ui/phantom-auto-trait.stderr

@@ -6,7 +6,6 @@ LL |     is_zen(x)
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required for `&T` to implement `Zen`
   --> $DIR/phantom-auto-trait.rs:10:24
    |
@@ -37,7 +36,6 @@ LL |     is_zen(x)
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required for `&T` to implement `Zen`
   --> $DIR/phantom-auto-trait.rs:10:24
    |

tests/ui/recursion/recursive-requirements.stderr

@@ -5,7 +5,6 @@ LL |     let _: AssertSync<Foo> = unimplemented!();
    |            ^^^^^^^^^^^^^^^ `*const Bar` cannot be shared between threads safely
    |
    = help: within `Foo`, the trait `Sync` is not implemented for `*const Bar`
-   = note: consider using `std::sync::Arc<*const Bar>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Foo`
   --> $DIR/recursive-requirements.rs:5:12
    |
@@ -24,7 +23,6 @@ LL |     let _: AssertSync<Foo> = unimplemented!();
    |            ^^^^^^^^^^^^^^^ `*const Foo` cannot be shared between threads safely
    |
    = help: within `Foo`, the trait `Sync` is not implemented for `*const Foo`
-   = note: consider using `std::sync::Arc<*const Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required because it appears within the type `Bar`
   --> $DIR/recursive-requirements.rs:10:12
    |

tests/ui/statics/issue-17718-static-sync.stderr

@@ -5,7 +5,6 @@ LL | static BAR: Foo = Foo;
    |             ^^^ `Foo` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `Foo`
-   = note: consider using `std::sync::Arc<Foo>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
    = note: shared static variables must have a type that implements `Sync`
 
 error: aborting due to previous error

tests/ui/stdlib-unit-tests/not-sync.stderr

@@ -33,7 +33,6 @@ LL |     test::<Rc<i32>>();
    |            ^^^^^^^ `Rc<i32>` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `Rc<i32>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required by a bound in `test`
   --> $DIR/not-sync.rs:5:12
    |
@@ -47,7 +46,6 @@ LL |     test::<Weak<i32>>();
    |            ^^^^^^^^^ `std::rc::Weak<i32>` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `std::rc::Weak<i32>`
-   = note: consider using `std::sync::Arc<std::rc::Weak<i32>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `test`
   --> $DIR/not-sync.rs:5:12
    |
@@ -61,7 +59,6 @@ LL |     test::<Receiver<i32>>();
    |            ^^^^^^^^^^^^^ `std::sync::mpsc::Receiver<i32>` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `std::sync::mpsc::Receiver<i32>`
-   = note: consider using `std::sync::Arc<std::sync::mpsc::Receiver<i32>>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `test`
   --> $DIR/not-sync.rs:5:12
    |

tests/ui/suggestions/issue-79843-impl-trait-with-missing-bounds-on-async-fn.stderr

@@ -7,7 +7,6 @@ LL |     assert_is_send(&bar);
    |     required by a bound introduced by this call
    |
    = help: the trait `Send` is not implemented for `<impl Foo as Foo>::Bar`
-   = note: consider using `std::sync::Arc<<impl Foo as Foo>::Bar>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_is_send`
   --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:30:22
    |
@@ -27,7 +26,6 @@ LL |     assert_is_send(&bar);
    |     required by a bound introduced by this call
    |
    = help: the trait `Send` is not implemented for `<impl Foo as Foo>::Bar`
-   = note: consider using `std::sync::Arc<<impl Foo as Foo>::Bar>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `assert_is_send`
   --> $DIR/issue-79843-impl-trait-with-missing-bounds-on-async-fn.rs:30:22
    |

tests/ui/suggestions/issue-84973-blacklist.stderr

@@ -71,7 +71,6 @@ LL |     f_send(rc);
    |     required by a bound introduced by this call
    |
    = help: the trait `Send` is not implemented for `Rc<{integer}>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
 note: required by a bound in `f_send`
   --> $DIR/issue-84973-blacklist.rs:10:14
    |

tests/ui/suggestions/restrict-type-argument.stderr

@@ -6,7 +6,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<impl Sync>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |
@@ -25,7 +24,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<S>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |
@@ -44,7 +42,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<S>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |
@@ -63,7 +60,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<S>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |
@@ -82,7 +78,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<S>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |
@@ -101,7 +96,6 @@ LL |     is_send(val);
    |     |
    |     required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<S>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `is_send`
   --> $DIR/restrict-type-argument.rs:1:15
    |

tests/ui/traits/alias/cross-crate.stderr

@@ -5,7 +5,6 @@ LL |     use_alias::<Rc<u32>>();
    |                 ^^^^^^^ `Rc<u32>` cannot be sent between threads safely
    |
    = help: the trait `Send` is not implemented for `Rc<u32>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
    = note: required for `Rc<u32>` to implement `SendSync`
 note: required by a bound in `use_alias`
   --> $DIR/cross-crate.rs:10:17
@@ -20,7 +19,6 @@ LL |     use_alias::<Rc<u32>>();
    |                 ^^^^^^^ `Rc<u32>` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `Rc<u32>`
-   = note: use `std::sync::Arc` instead of `std::rc::Rc`
    = note: required for `Rc<u32>` to implement `SendSync`
 note: required by a bound in `use_alias`
   --> $DIR/cross-crate.rs:10:17

tests/ui/traits/bad-method-typaram-kind.stderr

@@ -6,7 +6,6 @@ LL |     1.bar::<T>();
    |       |
    |       required by a bound introduced by this call
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `Bar::bar`
   --> $DIR/bad-method-typaram-kind.rs:6:14
    |

tests/ui/traits/inductive-overflow/two-traits.stderr

@@ -4,7 +4,6 @@ error[E0277]: `T` cannot be shared between threads safely
 LL |     type X = Self;
    |              ^^^^ `T` cannot be shared between threads safely
    |
-   = note: consider using `std::sync::Arc<T>`; for more information visit <https://doc.rust-lang.org/book/ch16-03-shared-state.html>
 note: required by a bound in `Magic::X`
   --> $DIR/two-traits.rs:8:13
    |