Merging upstream version 1.74.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

73 files changed, 664 insertions, 648 deletions

diff --git a/tests/ui/impl-trait/auto-trait-leak.rs b/tests/ui/impl-trait/auto-trait-leak.rs
index d71c09879..1f90292f4 100644
--- a/tests/ui/impl-trait/auto-trait-leak.rs
+++ b/tests/ui/impl-trait/auto-trait-leak.rs
@@ -12,7 +12,6 @@ fn cycle1() -> impl Clone {
     //~^ ERROR cycle detected
     //~| ERROR cycle detected
     send(cycle2().clone());
-    //~^ ERROR: cannot check whether the hidden type of opaque type satisfies auto traits
 
     Rc::new(Cell::new(5))
 }
diff --git a/tests/ui/impl-trait/auto-trait-leak.stderr b/tests/ui/impl-trait/auto-trait-leak.stderr
index a024cff0b..62341f6de 100644
--- a/tests/ui/impl-trait/auto-trait-leak.stderr
+++ b/tests/ui/impl-trait/auto-trait-leak.stderr
@@ -1,4 +1,4 @@
-error[E0391]: cycle detected when computing type of `cycle1::{opaque#0}`
+error[E0391]: cycle detected when computing type of opaque `cycle1::{opaque#0}`
   --> $DIR/auto-trait-leak.rs:11:16
    |
 LL | fn cycle1() -> impl Clone {
@@ -10,32 +10,26 @@ note: ...which requires type-checking `cycle1`...
 LL |     send(cycle2().clone());
    |     ^^^^
    = note: ...which requires evaluating trait selection obligation `cycle2::{opaque#0}: core::marker::Send`...
-note: ...which requires computing type of `cycle2::{opaque#0}`...
-  --> $DIR/auto-trait-leak.rs:20:16
+note: ...which requires computing type of opaque `cycle2::{opaque#0}`...
+  --> $DIR/auto-trait-leak.rs:19:16
    |
 LL | fn cycle2() -> impl Clone {
    |                ^^^^^^^^^^
 note: ...which requires type-checking `cycle2`...
-  --> $DIR/auto-trait-leak.rs:21:5
+  --> $DIR/auto-trait-leak.rs:20:5
    |
 LL |     send(cycle1().clone());
    |     ^^^^
    = note: ...which requires evaluating trait selection obligation `cycle1::{opaque#0}: core::marker::Send`...
-   = note: ...which again requires computing type of `cycle1::{opaque#0}`, completing the cycle
-note: cycle used when checking item types in top-level module
-  --> $DIR/auto-trait-leak.rs:1:1
-   |
-LL | / use std::cell::Cell;
-LL | | use std::rc::Rc;
-LL | |
-LL | | fn send<T: Send>(_: T) {}
-...  |
-LL | |     Rc::new(String::from("foo"))
-LL | | }
-   | |_^
+   = note: ...which again requires computing type of opaque `cycle1::{opaque#0}`, completing the cycle
+note: cycle used when computing type of `cycle1::{opaque#0}`
+  --> $DIR/auto-trait-leak.rs:11:16
+   |
+LL | fn cycle1() -> impl Clone {
+   |                ^^^^^^^^^^
    = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
 
-error[E0391]: cycle detected when computing type of `cycle1::{opaque#0}`
+error[E0391]: cycle detected when computing type of opaque `cycle1::{opaque#0}`
   --> $DIR/auto-trait-leak.rs:11:16
    |
 LL | fn cycle1() -> impl Clone {
@@ -47,32 +41,26 @@ note: ...which requires type-checking `cycle1`...
 LL |     send(cycle2().clone());
    |     ^^^^
    = note: ...which requires evaluating trait selection obligation `cycle2::{opaque#0}: core::marker::Send`...
-note: ...which requires computing type of `cycle2::{opaque#0}`...
-  --> $DIR/auto-trait-leak.rs:20:16
+note: ...which requires computing type of opaque `cycle2::{opaque#0}`...
+  --> $DIR/auto-trait-leak.rs:19:16
    |
 LL | fn cycle2() -> impl Clone {
    |                ^^^^^^^^^^
 note: ...which requires type-checking `cycle2`...
-  --> $DIR/auto-trait-leak.rs:20:1
+  --> $DIR/auto-trait-leak.rs:19:1
    |
 LL | fn cycle2() -> impl Clone {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which again requires computing type of `cycle1::{opaque#0}`, completing the cycle
-note: cycle used when checking item types in top-level module
-  --> $DIR/auto-trait-leak.rs:1:1
-   |
-LL | / use std::cell::Cell;
-LL | | use std::rc::Rc;
-LL | |
-LL | | fn send<T: Send>(_: T) {}
-...  |
-LL | |     Rc::new(String::from("foo"))
-LL | | }
-   | |_^
+   = note: ...which again requires computing type of opaque `cycle1::{opaque#0}`, completing the cycle
+note: cycle used when computing type of `cycle1::{opaque#0}`
+  --> $DIR/auto-trait-leak.rs:11:16
+   |
+LL | fn cycle1() -> impl Clone {
+   |                ^^^^^^^^^^
    = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
 
 error: cannot check whether the hidden type of opaque type satisfies auto traits
-  --> $DIR/auto-trait-leak.rs:21:10
+  --> $DIR/auto-trait-leak.rs:20:10
    |
 LL |     send(cycle1().clone());
    |     ---- ^^^^^^^^^^^^^^^^
@@ -85,7 +73,7 @@ note: opaque type is declared here
 LL | fn cycle1() -> impl Clone {
    |                ^^^^^^^^^^
 note: this item depends on auto traits of the hidden type, but may also be registering the hidden type. This is not supported right now. You can try moving the opaque type and the item that actually registers a hidden type into a new submodule
-  --> $DIR/auto-trait-leak.rs:20:4
+  --> $DIR/auto-trait-leak.rs:19:4
    |
 LL | fn cycle2() -> impl Clone {
    |    ^^^^^^
@@ -95,30 +83,6 @@ note: required by a bound in `send`
 LL | fn send<T: Send>(_: T) {}
    |            ^^^^ required by this bound in `send`
 
-error: cannot check whether the hidden type of opaque type satisfies auto traits
-  --> $DIR/auto-trait-leak.rs:14:10
-   |
-LL |     send(cycle2().clone());
-   |     ---- ^^^^^^^^^^^^^^^^
-   |     |
-   |     required by a bound introduced by this call
-   |
-note: opaque type is declared here
-  --> $DIR/auto-trait-leak.rs:20:16
-   |
-LL | fn cycle2() -> impl Clone {
-   |                ^^^^^^^^^^
-note: this item depends on auto traits of the hidden type, but may also be registering the hidden type. This is not supported right now. You can try moving the opaque type and the item that actually registers a hidden type into a new submodule
-  --> $DIR/auto-trait-leak.rs:11:4
-   |
-LL | fn cycle1() -> impl Clone {
-   |    ^^^^^^
-note: required by a bound in `send`
-  --> $DIR/auto-trait-leak.rs:4:12
-   |
-LL | fn send<T: Send>(_: T) {}
-   |            ^^^^ required by this bound in `send`
-
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0391`.
diff --git a/tests/ui/impl-trait/bound-normalization-fail.rs b/tests/ui/impl-trait/bound-normalization-fail.rs
index 332959247..566a4a7ad 100644
--- a/tests/ui/impl-trait/bound-normalization-fail.rs
+++ b/tests/ui/impl-trait/bound-normalization-fail.rs
@@ -39,8 +39,7 @@ mod lifetimes {
 
     /// Missing bound constraining `Assoc`, `T::Assoc` can't be normalized further.
     fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
-        //~^ ERROR `impl Trait` return type cannot contain a projection or `Self` that references lifetimes from a parent scope
-        //~| ERROR: type mismatch
+        //~^ ERROR: type mismatch
         Foo(())
     }
 }
diff --git a/tests/ui/impl-trait/bound-normalization-fail.stderr b/tests/ui/impl-trait/bound-normalization-fail.stderr
index f04a753a0..fcac9ac34 100644
--- a/tests/ui/impl-trait/bound-normalization-fail.stderr
+++ b/tests/ui/impl-trait/bound-normalization-fail.stderr
@@ -19,21 +19,12 @@ help: consider constraining the associated type `<T as impl_trait::Trait>::Assoc
 LL |     fn foo_fail<T: Trait<Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
    |                         ++++++++++++
 
-error[E0658]: `impl Trait` return type cannot contain a projection or `Self` that references lifetimes from a parent scope
-  --> $DIR/bound-normalization-fail.rs:41:41
-   |
-LL |     fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
-   |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #103532 <https://github.com/rust-lang/rust/issues/103532> for more information
-   = help: add `#![feature(impl_trait_projections)]` to the crate attributes to enable
-
 error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as Trait<'a>>::Assoc`
   --> $DIR/bound-normalization-fail.rs:41:41
    |
 LL |     fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
    |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type mismatch resolving `<Foo<()> as FooLike>::Output == <T as Trait<'a>>::Assoc`
-...
+LL |
 LL |         Foo(())
    |         ------- return type was inferred to be `Foo<()>` here
    |
@@ -49,7 +40,6 @@ help: consider constraining the associated type `<T as lifetimes::Trait<'a>>::As
 LL |     fn foo2_fail<'a, T: Trait<'a, Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
    |                                 ++++++++++++
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0271, E0658.
-For more information about an error, try `rustc --explain E0271`.
+For more information about this error, try `rustc --explain E0271`.
diff --git a/tests/ui/impl-trait/capture-lifetime-not-in-hir.rs b/tests/ui/impl-trait/capture-lifetime-not-in-hir.rs
new file mode 100644
index 000000000..9c067cb69
--- /dev/null
+++ b/tests/ui/impl-trait/capture-lifetime-not-in-hir.rs
@@ -0,0 +1,21 @@
+#![feature(rustc_attrs)]
+#![rustc_variance_of_opaques]
+
+trait Bar<'a> {
+    type Assoc: From<()>;
+}
+
+fn foo<'a, T: Bar<'a>>() -> impl Into<T::Assoc> {
+    //~^ ERROR [o, o]
+    // captures both T and 'a invariantly
+    ()
+}
+
+fn foo2<'a, T: Bar<'a>>() -> impl Into<T::Assoc> + 'a {
+    //~^ ERROR [o, o, o]
+    // captures both T and 'a invariantly, and also duplicates `'a`
+    // i.e. the opaque looks like `impl Into<<T as Bar<'a>>::Assoc> + 'a_duplicated`
+    ()
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/capture-lifetime-not-in-hir.stderr b/tests/ui/impl-trait/capture-lifetime-not-in-hir.stderr
new file mode 100644
index 000000000..9d52001b0
--- /dev/null
+++ b/tests/ui/impl-trait/capture-lifetime-not-in-hir.stderr
@@ -0,0 +1,14 @@
+error: [o, o]
+  --> $DIR/capture-lifetime-not-in-hir.rs:8:29
+   |
+LL | fn foo<'a, T: Bar<'a>>() -> impl Into<T::Assoc> {
+   |                             ^^^^^^^^^^^^^^^^^^^
+
+error: [o, o, o]
+  --> $DIR/capture-lifetime-not-in-hir.rs:14:30
+   |
+LL | fn foo2<'a, T: Bar<'a>>() -> impl Into<T::Assoc> + 'a {
+   |                              ^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
diff --git a/tests/ui/impl-trait/coherence-treats-tait-ambig.rs b/tests/ui/impl-trait/coherence-treats-tait-ambig.rs
index 156a7eb0e..df47208bf 100644
--- a/tests/ui/impl-trait/coherence-treats-tait-ambig.rs
+++ b/tests/ui/impl-trait/coherence-treats-tait-ambig.rs
@@ -1,6 +1,3 @@
-// revisions: current next
-//[next] compile-flags: -Ztrait-solver=next
-
 #![feature(type_alias_impl_trait)]
 
 type T = impl Sized;
diff --git a/tests/ui/impl-trait/coherence-treats-tait-ambig.next.stderr b/tests/ui/impl-trait/coherence-treats-tait-ambig.stderr
index 61fed1629..7c69c4bfe 100644
--- a/tests/ui/impl-trait/coherence-treats-tait-ambig.next.stderr
+++ b/tests/ui/impl-trait/coherence-treats-tait-ambig.stderr
@@ -1,5 +1,5 @@
 error[E0119]: conflicting implementations of trait `Into<T>` for type `Foo`
-  --> $DIR/coherence-treats-tait-ambig.rs:10:1
+  --> $DIR/coherence-treats-tait-ambig.rs:7:1
    |
 LL | impl Into<T> for Foo {
    | ^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr b/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr
new file mode 100644
index 000000000..83791f0d3
--- /dev/null
+++ b/tests/ui/impl-trait/equality-in-canonical-query.clone.stderr
@@ -0,0 +1,29 @@
+error: internal compiler error: no errors encountered even though `delay_span_bug` issued
+
+error: internal compiler error: {OpaqueTypeKey { def_id: DefId(rpit::{opaque#0}), args: [] }: OpaqueTypeDecl { hidden_type: OpaqueHiddenType { span: no-location (#0), ty: Alias(Opaque, AliasTy { args: [], def_id: DefId(foo::{opaque#0}) }) } }}
+   |
+   = 
+           
+
+error: internal compiler error: error performing ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: ProvePredicate { predicate: Binder { value: ProjectionPredicate(AliasTy { args: [FnDef(DefId(rpit), []), ()], def_id: DefId(ops::function::FnOnce::Output) }, Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(foo::{opaque#0}) }))), bound_vars: [] } } }
+  --> $DIR/equality-in-canonical-query.rs:19:5
+   |
+LL |     same_output(foo, rpit);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+
+  --> $DIR/equality-in-canonical-query.rs:19:5
+   |
+LL |     same_output(foo, rpit);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+
+
+
+
+
+
+
+query stack during panic:
+end of query stack
+error: aborting due to 3 previous errors
+
diff --git a/tests/ui/impl-trait/equality-in-canonical-query.rs b/tests/ui/impl-trait/equality-in-canonical-query.rs
new file mode 100644
index 000000000..672b1eeea
--- /dev/null
+++ b/tests/ui/impl-trait/equality-in-canonical-query.rs
@@ -0,0 +1,23 @@
+// issue: #116877
+// revisions: sized clone
+//[sized] check-pass
+
+//[clone] known-bug: #108498
+//[clone] failure-status: 101
+//[clone] normalize-stderr-test: "DefId\(.*?\]::" -> "DefId("
+//[clone] normalize-stderr-test: "(?m)note: .*$" -> ""
+//[clone] normalize-stderr-test: "(?m)^ *\d+: .*\n" -> ""
+//[clone] normalize-stderr-test: "(?m)^ *at .*\n" -> ""
+
+#[cfg(sized)] fn rpit() -> impl Sized {}
+#[cfg(clone)] fn rpit() -> impl Clone {}
+
+fn same_output<Out>(_: impl Fn() -> Out, _: impl Fn() -> Out) {}
+
+pub fn foo() -> impl Sized {
+    same_output(rpit, foo);
+    same_output(foo, rpit);
+    rpit()
+}
+
+fn main () {}
diff --git a/tests/ui/impl-trait/feature-self-return-type.rs b/tests/ui/impl-trait/feature-self-return-type.rs
index 51877e9cc..7555df1b2 100644
--- a/tests/ui/impl-trait/feature-self-return-type.rs
+++ b/tests/ui/impl-trait/feature-self-return-type.rs
@@ -1,5 +1,4 @@
 // edition:2018
-#![feature(impl_trait_projections)]
 
 // This test checks that we emit the correct borrowck error when `Self` or a projection is used as
 // a return type.  See #61949 for context.
diff --git a/tests/ui/impl-trait/feature-self-return-type.stderr b/tests/ui/impl-trait/feature-self-return-type.stderr
index b9b8d00ce..e7113a9df 100644
--- a/tests/ui/impl-trait/feature-self-return-type.stderr
+++ b/tests/ui/impl-trait/feature-self-return-type.stderr
@@ -1,5 +1,5 @@
 error[E0597]: `bar` does not live long enough
-  --> $DIR/feature-self-return-type.rs:23:22
+  --> $DIR/feature-self-return-type.rs:22:22
    |
 LL |         let x = {
    |             - borrow later stored here
@@ -12,7 +12,7 @@ LL |         };
    |         - `bar` dropped here while still borrowed
 
 error[E0597]: `y` does not live long enough
-  --> $DIR/feature-self-return-type.rs:63:17
+  --> $DIR/feature-self-return-type.rs:62:17
    |
 LL |         let x = {
    |             - borrow later stored here
@@ -25,7 +25,7 @@ LL |         };
    |         - `y` dropped here while still borrowed
 
 error[E0597]: `y` does not live long enough
-  --> $DIR/feature-self-return-type.rs:95:17
+  --> $DIR/feature-self-return-type.rs:94:17
    |
 LL |         let x = {
    |             - borrow later stored here
diff --git a/tests/ui/impl-trait/impl-subtyper.rs b/tests/ui/impl-trait/impl-subtyper.rs
new file mode 100644
index 000000000..2d99cdd4f
--- /dev/null
+++ b/tests/ui/impl-trait/impl-subtyper.rs
@@ -0,0 +1,18 @@
+// check-pass
+
+#![crate_type = "lib"]
+fn checkpoints() -> impl Iterator {
+    Some(()).iter().flat_map(|_| std::iter::once(()))
+}
+
+fn block_checkpoints() -> impl Iterator {
+    checkpoints()
+}
+
+fn iter_raw() -> impl Iterator {
+    let mut iter = block_checkpoints();
+
+    (0..9).map(move |_| {
+        iter.next();
+    })
+}
diff --git a/tests/ui/impl-trait/impl-subtyper2.rs b/tests/ui/impl-trait/impl-subtyper2.rs
new file mode 100644
index 000000000..2e0acbae6
--- /dev/null
+++ b/tests/ui/impl-trait/impl-subtyper2.rs
@@ -0,0 +1,7 @@
+// check-pass
+
+fn ages() -> Option<impl Iterator> {
+    None::<std::slice::Iter<()>>
+}
+
+fn main(){}
diff --git a/tests/ui/impl-trait/in-trait/anonymize-binders-for-refine.rs b/tests/ui/impl-trait/in-trait/anonymize-binders-for-refine.rs
new file mode 100644
index 000000000..e62662f2f
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/anonymize-binders-for-refine.rs
@@ -0,0 +1,13 @@
+// compile-flags: --crate-type=lib
+// check-pass
+
+#![feature(return_position_impl_trait_in_trait)]
+#![deny(refining_impl_trait)]
+
+pub trait Tr<T> {
+    fn foo() -> impl for<'a> Tr<&'a Self>;
+}
+
+impl<T> Tr<T> for () {
+    fn foo() -> impl for<'a> Tr<&'a Self> {}
+}
diff --git a/tests/ui/impl-trait/in-trait/auxiliary/rpitit.rs b/tests/ui/impl-trait/in-trait/auxiliary/rpitit.rs
index cfc2193f6..6e9940211 100644
--- a/tests/ui/impl-trait/in-trait/auxiliary/rpitit.rs
+++ b/tests/ui/impl-trait/in-trait/auxiliary/rpitit.rs
@@ -1,4 +1,4 @@
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 
 use std::ops::Deref;
 
@@ -8,6 +8,7 @@ pub trait Foo {
 
 pub struct Foreign;
 impl Foo for Foreign {
+    #[expect(refining_impl_trait)]
     fn bar(self) -> &'static () {
         &()
     }
diff --git a/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.rs b/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.rs
index ff7ad4bf3..fbbbb8585 100644
--- a/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.rs
+++ b/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.rs
@@ -2,7 +2,7 @@
 
 #![feature(return_position_impl_trait_in_trait)]
 
-trait Iterable {
+pub trait Iterable {
     type Item<'a>
     where
         Self: 'a;
@@ -17,6 +17,7 @@ impl<'a, I: 'a + Iterable> Iterable for &'a I {
     //~^ ERROR impl has stricter requirements than trait
 
     fn iter(&self) -> impl 'a + Iterator<Item = I::Item<'a>> {
+        //~^ WARN impl trait in impl method signature does not match trait method signature
         (*self).iter()
     }
 }
diff --git a/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.stderr b/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.stderr
index 106b8a7c8..a5fb338ea 100644
--- a/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.stderr
+++ b/tests/ui/impl-trait/in-trait/bad-item-bound-within-rpitit.stderr
@@ -12,6 +12,22 @@ help: copy the `where` clause predicates from the trait
 LL |     where Self: 'b;
    |     ~~~~~~~~~~~~~~
 
-error: aborting due to previous error
+warning: impl trait in impl method signature does not match trait method signature
+  --> $DIR/bad-item-bound-within-rpitit.rs:19:28
+   |
+LL |     fn iter(&self) -> impl '_ + Iterator<Item = Self::Item<'_>>;
+   |                       ----------------------------------------- return type from trait method defined here
+...
+LL |     fn iter(&self) -> impl 'a + Iterator<Item = I::Item<'a>> {
+   |                            ^^ this bound is stronger than that defined on the trait
+   |
+   = note: add `#[allow(refining_impl_trait)]` if it is intended for this to be part of the public API of this crate
+   = note: `#[warn(refining_impl_trait)]` on by default
+help: replace the return type so that it matches the trait
+   |
+LL |     fn iter(&self) -> impl Iterator<Item = <Self as Iterable>::Item<'_>> + '_ {
+   |                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0276`.
diff --git a/tests/ui/impl-trait/in-trait/deep-match-works.rs b/tests/ui/impl-trait/in-trait/deep-match-works.rs
index 78cff97c6..fc290f11f 100644
--- a/tests/ui/impl-trait/in-trait/deep-match-works.rs
+++ b/tests/ui/impl-trait/in-trait/deep-match-works.rs
@@ -1,15 +1,16 @@
 // check-pass
 
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 #![allow(incomplete_features)]
 
-struct Wrapper<T>(T);
+pub struct Wrapper<T>(T);
 
-trait Foo {
+pub trait Foo {
     fn bar() -> Wrapper<impl Sized>;
 }
 
 impl Foo for () {
+    #[expect(refining_impl_trait)]
     fn bar() -> Wrapper<i32> {
         Wrapper(0)
     }
diff --git a/tests/ui/impl-trait/in-trait/foreign.rs b/tests/ui/impl-trait/in-trait/foreign.rs
index b0c93a029..6285d7786 100644
--- a/tests/ui/impl-trait/in-trait/foreign.rs
+++ b/tests/ui/impl-trait/in-trait/foreign.rs
@@ -1,14 +1,25 @@
 // check-pass
 // aux-build: rpitit.rs
 
+#![feature(lint_reasons)]
+
 extern crate rpitit;
 
 use rpitit::{Foo, Foreign};
 use std::sync::Arc;
 
 // Implement an RPITIT from another crate.
-struct Local;
+pub struct Local;
 impl Foo for Local {
+    #[expect(refining_impl_trait)]
+    fn bar(self) -> Arc<String> {
+        Arc::new(String::new())
+    }
+}
+
+struct LocalIgnoreRefining;
+impl Foo for LocalIgnoreRefining {
+    #[deny(refining_impl_trait)]
     fn bar(self) -> Arc<String> {
         Arc::new(String::new())
     }
@@ -23,4 +34,5 @@ fn main() {
     let &() = Foreign.bar();
 
     let x: Arc<String> = Local.bar();
+    let x: Arc<String> = LocalIgnoreRefining.bar();
 }
diff --git a/tests/ui/impl-trait/in-trait/issue-102140.stderr b/tests/ui/impl-trait/in-trait/issue-102140.stderr
index 5d55b9fa4..18bb63745 100644
--- a/tests/ui/impl-trait/in-trait/issue-102140.stderr
+++ b/tests/ui/impl-trait/in-trait/issue-102140.stderr
@@ -6,7 +6,11 @@ LL |         MyTrait::foo(&self)
    |         |
    |         required by a bound introduced by this call
    |
-   = help: the trait `MyTrait` is implemented for `Outer`
+help: consider removing the leading `&`-reference
+   |
+LL -         MyTrait::foo(&self)
+LL +         MyTrait::foo(self)
+   |
 
 error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
   --> $DIR/issue-102140.rs:23:9
diff --git a/tests/ui/impl-trait/in-trait/issue-102571.rs b/tests/ui/impl-trait/in-trait/issue-102571.rs
index 61c91e644..ccb53031c 100644
--- a/tests/ui/impl-trait/in-trait/issue-102571.rs
+++ b/tests/ui/impl-trait/in-trait/issue-102571.rs
@@ -8,14 +8,6 @@ trait Foo {
     fn bar(self) -> impl Deref<Target = impl Display + ?Sized>;
 }
 
-struct A;
-
-impl Foo for A {
-    fn bar(self) -> &'static str {
-        "Hello, world"
-    }
-}
-
 fn foo<T: Foo>(t: T) {
     let () = t.bar();
     //~^ ERROR mismatched types
diff --git a/tests/ui/impl-trait/in-trait/issue-102571.stderr b/tests/ui/impl-trait/in-trait/issue-102571.stderr
index 87219941d..594b9ae9c 100644
--- a/tests/ui/impl-trait/in-trait/issue-102571.stderr
+++ b/tests/ui/impl-trait/in-trait/issue-102571.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/issue-102571.rs:20:9
+  --> $DIR/issue-102571.rs:12:9
    |
 LL |     let () = t.bar();
    |         ^^   ------- this expression has type `impl Deref<Target = impl std::fmt::Display + ?Sized>`
diff --git a/tests/ui/impl-trait/in-trait/lifetime-in-associated-trait-bound.rs b/tests/ui/impl-trait/in-trait/lifetime-in-associated-trait-bound.rs
new file mode 100644
index 000000000..49d36d6c9
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/lifetime-in-associated-trait-bound.rs
@@ -0,0 +1,19 @@
+// check-pass
+
+#![feature(associated_type_bounds, return_position_impl_trait_in_trait)]
+
+trait Trait {
+    type Type;
+
+    fn method(&self) -> impl Trait<Type: '_>;
+}
+
+impl Trait for () {
+    type Type = ();
+
+    fn method(&self) -> impl Trait<Type: '_> {
+        ()
+    }
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/in-trait/nested-rpitit.rs b/tests/ui/impl-trait/in-trait/nested-rpitit.rs
index 65285e3a3..58ba1acaf 100644
--- a/tests/ui/impl-trait/in-trait/nested-rpitit.rs
+++ b/tests/ui/impl-trait/in-trait/nested-rpitit.rs
@@ -1,26 +1,28 @@
 // check-pass
 
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 #![allow(incomplete_features)]
 
 use std::fmt::Display;
 use std::ops::Deref;
 
-trait Foo {
+pub trait Foo {
     fn bar(self) -> impl Deref<Target = impl Display + ?Sized>;
 }
 
-struct A;
+pub struct A;
 
 impl Foo for A {
+    #[expect(refining_impl_trait)]
     fn bar(self) -> &'static str {
         "Hello, world"
     }
 }
 
-struct B;
+pub struct B;
 
 impl Foo for B {
+    #[expect(refining_impl_trait)]
     fn bar(self) -> Box<i32> {
         Box::new(42)
     }
diff --git a/tests/ui/impl-trait/in-trait/object-safety-sized.rs b/tests/ui/impl-trait/in-trait/object-safety-sized.rs
new file mode 100644
index 000000000..f221cfbb1
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/object-safety-sized.rs
@@ -0,0 +1,23 @@
+// check-pass
+// revisions: current next
+//[next] compile-flags: -Ztrait-solver=next
+
+#![feature(return_position_impl_trait_in_trait)]
+
+fn main() {
+    let vec: Vec<Box<dyn Trait>> = Vec::new();
+
+    for i in vec {
+        i.fn_2();
+    }
+}
+
+trait OtherTrait {}
+
+trait Trait {
+    fn fn_1(&self) -> impl OtherTrait
+    where
+        Self: Sized;
+
+    fn fn_2(&self) -> bool;
+}
diff --git a/tests/ui/impl-trait/in-trait/object-safety.rs b/tests/ui/impl-trait/in-trait/object-safety.rs
index dd35b9a2d..d1c9fba4e 100644
--- a/tests/ui/impl-trait/in-trait/object-safety.rs
+++ b/tests/ui/impl-trait/in-trait/object-safety.rs
@@ -8,7 +8,7 @@ trait Foo {
 }
 
 impl Foo for u32 {
-    fn baz(&self) -> u32 {
+    fn baz(&self) -> impl Debug {
         32
     }
 }
@@ -19,4 +19,5 @@ fn main() {
     //~| ERROR the trait `Foo` cannot be made into an object
     let s = i.baz();
     //~^ ERROR the trait `Foo` cannot be made into an object
+    //~| ERROR the trait `Foo` cannot be made into an object
 }
diff --git a/tests/ui/impl-trait/in-trait/object-safety.stderr b/tests/ui/impl-trait/in-trait/object-safety.stderr
index 4a3b3b114..0170dc5d0 100644
--- a/tests/ui/impl-trait/in-trait/object-safety.stderr
+++ b/tests/ui/impl-trait/in-trait/object-safety.stderr
@@ -14,6 +14,21 @@ LL |     fn baz(&self) -> impl Debug;
    = help: consider moving `baz` to another trait
 
 error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-safety.rs:20:15
+   |
+LL |     let s = i.baz();
+   |               ^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-safety.rs:7:22
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     fn baz(&self) -> impl Debug;
+   |                      ^^^^^^^^^^ ...because method `baz` references an `impl Trait` type in its return type
+   = help: consider moving `baz` to another trait
+
+error[E0038]: the trait `Foo` cannot be made into an object
   --> $DIR/object-safety.rs:20:13
    |
 LL |     let s = i.baz();
@@ -44,6 +59,6 @@ LL |     fn baz(&self) -> impl Debug;
    = help: consider moving `baz` to another trait
    = note: required for the cast from `Box<u32>` to `Box<dyn Foo>`
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0038`.
diff --git a/tests/ui/impl-trait/in-trait/refine.rs b/tests/ui/impl-trait/in-trait/refine.rs
new file mode 100644
index 000000000..a91f9b3e7
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/refine.rs
@@ -0,0 +1,48 @@
+#![feature(return_position_impl_trait_in_trait, async_fn_in_trait)]
+#![deny(refining_impl_trait)]
+
+pub trait Foo {
+    fn bar() -> impl Sized;
+}
+
+pub struct A;
+impl Foo for A {
+    fn bar() -> impl Copy {}
+    //~^ ERROR impl method signature does not match trait method signature
+}
+
+pub struct B;
+impl Foo for B {
+    fn bar() {}
+    //~^ ERROR impl method signature does not match trait method signature
+}
+
+pub struct C;
+impl Foo for C {
+    fn bar() -> () {}
+    //~^ ERROR impl method signature does not match trait method signature
+}
+
+struct Private;
+impl Foo for Private {
+    fn bar() -> () {}
+}
+
+pub trait Arg<A> {
+    fn bar() -> impl Sized;
+}
+impl Arg<Private> for A {
+    fn bar() -> () {}
+}
+
+pub trait Late {
+    fn bar<'a>(&'a self) -> impl Sized + 'a;
+}
+
+pub struct D;
+impl Late for D {
+    fn bar(&self) -> impl Copy + '_ {}
+    //~^ ERROR impl method signature does not match trait method signature
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/in-trait/refine.stderr b/tests/ui/impl-trait/in-trait/refine.stderr
new file mode 100644
index 000000000..29aa08e25
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/refine.stderr
@@ -0,0 +1,67 @@
+error: impl trait in impl method signature does not match trait method signature
+  --> $DIR/refine.rs:10:22
+   |
+LL |     fn bar() -> impl Sized;
+   |                 ---------- return type from trait method defined here
+...
+LL |     fn bar() -> impl Copy {}
+   |                      ^^^^ this bound is stronger than that defined on the trait
+   |
+   = note: add `#[allow(refining_impl_trait)]` if it is intended for this to be part of the public API of this crate
+note: the lint level is defined here
+  --> $DIR/refine.rs:2:9
+   |
+LL | #![deny(refining_impl_trait)]
+   |         ^^^^^^^^^^^^^^^^^^^
+help: replace the return type so that it matches the trait
+   |
+LL |     fn bar() -> impl Sized {}
+   |                 ~~~~~~~~~~
+
+error: impl trait in impl method signature does not match trait method signature
+  --> $DIR/refine.rs:16:5
+   |
+LL |     fn bar() -> impl Sized;
+   |                 ---------- return type from trait method defined here
+...
+LL |     fn bar() {}
+   |     ^^^^^^^^
+   |
+   = note: add `#[allow(refining_impl_trait)]` if it is intended for this to be part of the public API of this crate
+help: replace the return type so that it matches the trait
+   |
+LL |     fn bar() -> impl Sized {}
+   |              +++++++++++++
+
+error: impl trait in impl method signature does not match trait method signature
+  --> $DIR/refine.rs:22:17
+   |
+LL |     fn bar() -> impl Sized;
+   |                 ---------- return type from trait method defined here
+...
+LL |     fn bar() -> () {}
+   |                 ^^
+   |
+   = note: add `#[allow(refining_impl_trait)]` if it is intended for this to be part of the public API of this crate
+help: replace the return type so that it matches the trait
+   |
+LL |     fn bar() -> impl Sized {}
+   |                 ~~~~~~~~~~
+
+error: impl trait in impl method signature does not match trait method signature
+  --> $DIR/refine.rs:44:27
+   |
+LL |     fn bar<'a>(&'a self) -> impl Sized + 'a;
+   |                             --------------- return type from trait method defined here
+...
+LL |     fn bar(&self) -> impl Copy + '_ {}
+   |                           ^^^^ this bound is stronger than that defined on the trait
+   |
+   = note: add `#[allow(refining_impl_trait)]` if it is intended for this to be part of the public API of this crate
+help: replace the return type so that it matches the trait
+   |
+LL |     fn bar(&self) -> impl Sized + '_ {}
+   |                      ~~~~~~~~~~~~~~~
+
+error: aborting due to 4 previous errors
+
diff --git a/tests/ui/impl-trait/in-trait/reveal.rs b/tests/ui/impl-trait/in-trait/reveal.rs
index d6ede1cc4..b1b46d75b 100644
--- a/tests/ui/impl-trait/in-trait/reveal.rs
+++ b/tests/ui/impl-trait/in-trait/reveal.rs
@@ -1,13 +1,14 @@
 // check-pass
 
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 #![allow(incomplete_features)]
 
-trait Foo {
+pub trait Foo {
     fn f() -> Box<impl Sized>;
 }
 
 impl Foo for () {
+    #[expect(refining_impl_trait)]
     fn f() -> Box<String> {
         Box::new(String::new())
     }
diff --git a/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.rs b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.rs
new file mode 100644
index 000000000..5e14a7f8e
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.rs
@@ -0,0 +1,26 @@
+#![feature(return_position_impl_trait_in_trait)]
+
+trait Extend {
+    fn extend<'a: 'a>(_: &'a str) -> (impl Sized + 'a, &'static str);
+}
+
+impl Extend for () {
+    fn extend<'a: 'a>(s: &'a str) -> (Option<&'static &'a ()>, &'static str)
+    //~^ ERROR in type `&'static &'a ()`, reference has a longer lifetime than the data it references
+    where
+        'a: 'static,
+    {
+        (None, s)
+    }
+}
+
+// This indirection is not necessary for reproduction,
+// but it makes this test future-proof against #114936.
+fn extend<T: Extend>(s: &str) -> &'static str {
+    <T as Extend>::extend(s).1
+}
+
+fn main() {
+    let use_after_free = extend::<()>(&String::from("temporary"));
+    println!("{}", use_after_free);
+}
diff --git a/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.stderr b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.stderr
new file mode 100644
index 000000000..1d947310e
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf-via-param.stderr
@@ -0,0 +1,16 @@
+error[E0491]: in type `&'static &'a ()`, reference has a longer lifetime than the data it references
+  --> $DIR/rpitit-hidden-types-self-implied-wf-via-param.rs:8:38
+   |
+LL |     fn extend<'a: 'a>(s: &'a str) -> (Option<&'static &'a ()>, &'static str)
+   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the pointer is valid for the static lifetime
+note: but the referenced data is only valid for the lifetime `'a` as defined here
+  --> $DIR/rpitit-hidden-types-self-implied-wf-via-param.rs:8:15
+   |
+LL |     fn extend<'a: 'a>(s: &'a str) -> (Option<&'static &'a ()>, &'static str)
+   |               ^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0491`.
diff --git a/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.rs b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.rs
new file mode 100644
index 000000000..c1885af4e
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.rs
@@ -0,0 +1,23 @@
+#![feature(return_position_impl_trait_in_trait)]
+
+trait Extend {
+    fn extend(_: &str) -> (impl Sized + '_, &'static str);
+}
+
+impl Extend for () {
+    fn extend(s: &str) -> (Option<&'static &'_ ()>, &'static str) {
+        //~^ ERROR in type `&'static &()`, reference has a longer lifetime than the data it references
+        (None, s)
+    }
+}
+
+// This indirection is not necessary for reproduction,
+// but it makes this test future-proof against #114936.
+fn extend<T: Extend>(s: &str) -> &'static str {
+    <T as Extend>::extend(s).1
+}
+
+fn main() {
+    let use_after_free = extend::<()>(&String::from("temporary"));
+    println!("{}", use_after_free);
+}
diff --git a/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.stderr b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.stderr
new file mode 100644
index 000000000..7b63e72ac
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/rpitit-hidden-types-self-implied-wf.stderr
@@ -0,0 +1,16 @@
+error[E0491]: in type `&'static &()`, reference has a longer lifetime than the data it references
+  --> $DIR/rpitit-hidden-types-self-implied-wf.rs:8:27
+   |
+LL |     fn extend(s: &str) -> (Option<&'static &'_ ()>, &'static str) {
+   |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the pointer is valid for the static lifetime
+note: but the referenced data is only valid for the anonymous lifetime defined here
+  --> $DIR/rpitit-hidden-types-self-implied-wf.rs:8:18
+   |
+LL |     fn extend(s: &str) -> (Option<&'static &'_ ()>, &'static str) {
+   |                  ^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0491`.
diff --git a/tests/ui/impl-trait/in-trait/rpitit-shadowed-by-missing-adt.rs b/tests/ui/impl-trait/in-trait/rpitit-shadowed-by-missing-adt.rs
index 7682884f8..44a2b4303 100644
--- a/tests/ui/impl-trait/in-trait/rpitit-shadowed-by-missing-adt.rs
+++ b/tests/ui/impl-trait/in-trait/rpitit-shadowed-by-missing-adt.rs
@@ -1,6 +1,6 @@
 // issue: 113903
 
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 
 use std::ops::Deref;
 
@@ -10,6 +10,7 @@ pub trait Tr {
 }
 
 impl Tr for () {
+    #[expect(refining_impl_trait)]
     fn w() -> &'static () {
         &()
     }
diff --git a/tests/ui/impl-trait/in-trait/signature-mismatch.failure.stderr b/tests/ui/impl-trait/in-trait/signature-mismatch.failure.stderr
new file mode 100644
index 000000000..468cf12f1
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/signature-mismatch.failure.stderr
@@ -0,0 +1,14 @@
+error[E0623]: lifetime mismatch
+  --> $DIR/signature-mismatch.rs:79:10
+   |
+LL |         &'a self,
+   |         -------- this parameter and the return type are declared with different lifetimes...
+...
+LL |     ) -> impl Future<Output = Vec<u8>> {
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |          |
+   |          ...but data from `buff` is returned here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0623`.
diff --git a/tests/ui/impl-trait/in-trait/signature-mismatch.rs b/tests/ui/impl-trait/in-trait/signature-mismatch.rs
index 1d63a6f3c..685c0f06e 100644
--- a/tests/ui/impl-trait/in-trait/signature-mismatch.rs
+++ b/tests/ui/impl-trait/in-trait/signature-mismatch.rs
@@ -1,26 +1,36 @@
 // edition:2021
+// revisions: success failure
+//[success] check-pass
 
-#![feature(return_position_impl_trait_in_trait)]
-#![allow(incomplete_features)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 
 use std::future::Future;
 
-trait Captures<'a> {}
+pub trait Captures<'a> {}
 impl<T> Captures<'_> for T {}
 
-trait Captures2<'a, 'b> {}
+pub trait Captures2<'a, 'b> {}
 impl<T> Captures2<'_, '_> for T {}
 
 pub trait AsyncTrait {
+    #[cfg(success)]
     fn async_fn(&self, buff: &[u8]) -> impl Future<Output = Vec<u8>>;
+
+    #[cfg(success)]
     fn async_fn_early<'a: 'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>>;
+
+    #[cfg(success)]
     fn async_fn_multiple<'a>(&'a self, buff: &[u8])
-        -> impl Future<Output = Vec<u8>> + Captures<'a>;
+    -> impl Future<Output = Vec<u8>> + Captures<'a>;
+
+    #[cfg(failure)]
     fn async_fn_reduce_outlive<'a, T>(
         &'a self,
         buff: &[u8],
         t: T,
     ) -> impl Future<Output = Vec<u8>> + 'a;
+
+    #[cfg(success)]
     fn async_fn_reduce<'a, T>(
         &'a self,
         buff: &[u8],
@@ -31,38 +41,52 @@ pub trait AsyncTrait {
 pub struct Struct;
 
 impl AsyncTrait for Struct {
+    // Does not capture more lifetimes that trait def'n, since trait def'n
+    // implicitly captures all in-scope lifetimes.
+    #[cfg(success)]
+    #[expect(refining_impl_trait)]
     fn async_fn<'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
-        //~^ ERROR return type captures more lifetimes than trait definition
         async move { buff.to_vec() }
     }
 
+    // Does not capture more lifetimes that trait def'n, since trait def'n
+    // implicitly captures all in-scope lifetimes.
+    #[cfg(success)]
+    #[expect(refining_impl_trait)]
     fn async_fn_early<'a: 'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
-        //~^ ERROR return type captures more lifetimes than trait definition
         async move { buff.to_vec() }
     }
 
+    // Does not capture more lifetimes that trait def'n, since trait def'n
+    // implicitly captures all in-scope lifetimes.
+    #[cfg(success)]
+    #[expect(refining_impl_trait)]
     fn async_fn_multiple<'a, 'b>(
         &'a self,
         buff: &'b [u8],
     ) -> impl Future<Output = Vec<u8>> + Captures2<'a, 'b> {
-        //~^ ERROR return type captures more lifetimes than trait definition
         async move { buff.to_vec() }
     }
 
+    // This error message is awkward, but `impl Future<Output = Vec<u8>>`
+    // cannot outlive `'a` (from the trait signature) because it captures
+    // both `T` and `'b`.
+    #[cfg(failure)]
     fn async_fn_reduce_outlive<'a, 'b, T>(
         &'a self,
         buff: &'b [u8],
         t: T,
     ) -> impl Future<Output = Vec<u8>> {
-        //~^ ERROR the parameter type `T` may not live long enough
+        //[failure]~^ ERROR lifetime mismatch
         async move {
             let _t = t;
             vec![]
         }
     }
 
-    // OK: We remove the `Captures<'a>`, providing a guarantee that we don't capture `'a`,
-    // but we still fulfill the `Captures<'a>` trait bound.
+    // Does not capture fewer lifetimes that trait def'n (not that it matters),
+    // since impl also captures all in-scope lifetimes.
+    #[cfg(success)]
     fn async_fn_reduce<'a, 'b, T>(&'a self, buff: &'b [u8], t: T) -> impl Future<Output = Vec<u8>> {
         async move {
             let _t = t;
diff --git a/tests/ui/impl-trait/in-trait/signature-mismatch.stderr b/tests/ui/impl-trait/in-trait/signature-mismatch.stderr
deleted file mode 100644
index 616f1ac35..000000000
--- a/tests/ui/impl-trait/in-trait/signature-mismatch.stderr
+++ /dev/null
@@ -1,61 +0,0 @@
-error: return type captures more lifetimes than trait definition
-  --> $DIR/signature-mismatch.rs:34:47
-   |
-LL |     fn async_fn<'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
-   |                 -- this lifetime was captured ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: hidden type must only reference lifetimes captured by this impl trait
-  --> $DIR/signature-mismatch.rs:15:40
-   |
-LL |     fn async_fn(&self, buff: &[u8]) -> impl Future<Output = Vec<u8>>;
-   |                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: hidden type inferred to be `impl Future<Output = Vec<u8>> + 'a`
-
-error: return type captures more lifetimes than trait definition
-  --> $DIR/signature-mismatch.rs:39:57
-   |
-LL |     fn async_fn_early<'a: 'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
-   |                       -- this lifetime was captured     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: hidden type must only reference lifetimes captured by this impl trait
-  --> $DIR/signature-mismatch.rs:16:57
-   |
-LL |     fn async_fn_early<'a: 'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>>;
-   |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: hidden type inferred to be `impl Future<Output = Vec<u8>> + 'a`
-
-error: return type captures more lifetimes than trait definition
-  --> $DIR/signature-mismatch.rs:47:10
-   |
-LL |     fn async_fn_multiple<'a, 'b>(
-   |                              -- this lifetime was captured
-...
-LL |     ) -> impl Future<Output = Vec<u8>> + Captures2<'a, 'b> {
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: hidden type must only reference lifetimes captured by this impl trait
-  --> $DIR/signature-mismatch.rs:18:12
-   |
-LL |         -> impl Future<Output = Vec<u8>> + Captures<'a>;
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: hidden type inferred to be `impl Future<Output = Vec<u8>> + Captures2<'a, 'b>`
-
-error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/signature-mismatch.rs:56:10
-   |
-LL |     ) -> impl Future<Output = Vec<u8>> {
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `impl Future<Output = Vec<u8>>` will meet its required lifetime bounds...
-   |
-note: ...that is required by this bound
-  --> $DIR/signature-mismatch.rs:23:42
-   |
-LL |     ) -> impl Future<Output = Vec<u8>> + 'a;
-   |                                          ^^
-help: consider adding an explicit lifetime bound...
-   |
-LL |     fn async_fn_reduce_outlive<'a, 'b, T: 'a>(
-   |                                         ++++
-
-error: aborting due to 4 previous errors
-
-For more information about this error, try `rustc --explain E0309`.
diff --git a/tests/ui/impl-trait/in-trait/specialization-substs-remap.rs b/tests/ui/impl-trait/in-trait/specialization-substs-remap.rs
index c9ee877db..41fc28588 100644
--- a/tests/ui/impl-trait/in-trait/specialization-substs-remap.rs
+++ b/tests/ui/impl-trait/in-trait/specialization-substs-remap.rs
@@ -1,10 +1,10 @@
 // check-pass
 
 #![feature(specialization)]
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 #![allow(incomplete_features)]
 
-trait Foo {
+pub trait Foo {
     fn bar(&self) -> impl Sized;
 }
 
@@ -12,6 +12,7 @@ impl<U> Foo for U
 where
     U: Copy,
 {
+    #[expect(refining_impl_trait)]
     fn bar(&self) -> U {
         *self
     }
diff --git a/tests/ui/impl-trait/in-trait/success.rs b/tests/ui/impl-trait/in-trait/success.rs
index 4cbe682b4..7d415ea17 100644
--- a/tests/ui/impl-trait/in-trait/success.rs
+++ b/tests/ui/impl-trait/in-trait/success.rs
@@ -1,29 +1,32 @@
 // check-pass
 
-#![feature(return_position_impl_trait_in_trait)]
+#![feature(return_position_impl_trait_in_trait, lint_reasons)]
 #![allow(incomplete_features)]
 
 use std::fmt::Display;
 
-trait Foo {
+pub trait Foo {
     fn bar(&self) -> impl Display;
 }
 
 impl Foo for i32 {
+    #[expect(refining_impl_trait)]
     fn bar(&self) -> i32 {
         *self
     }
 }
 
 impl Foo for &'static str {
+    #[expect(refining_impl_trait)]
     fn bar(&self) -> &'static str {
         *self
     }
 }
 
-struct Yay;
+pub struct Yay;
 
 impl Foo for Yay {
+    #[expect(refining_impl_trait)]
     fn bar(&self) -> String {
         String::from(":^)")
     }
diff --git a/tests/ui/impl-trait/in-trait/variance.rs b/tests/ui/impl-trait/in-trait/variance.rs
new file mode 100644
index 000000000..f8e4ab88c
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/variance.rs
@@ -0,0 +1,20 @@
+#![feature(rustc_attrs, return_position_impl_trait_in_trait)]
+#![allow(internal_features)]
+#![rustc_variance_of_opaques]
+
+trait Captures<'a> {}
+impl<T> Captures<'_> for T {}
+
+trait Foo<'i> {
+    fn implicit_capture_early<'a: 'a>() -> impl Sized {}
+    //~^ [o, *, *, o, o]
+    // Self, 'i, 'a, 'i_duplicated, 'a_duplicated
+
+    fn explicit_capture_early<'a: 'a>() -> impl Sized + Captures<'a> {} //~ [o, *, *, o, o]
+
+    fn implicit_capture_late<'a>(_: &'a ()) -> impl Sized {} //~ [o, *, o, o]
+
+    fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {} //~ [o, *, o, o]
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/in-trait/variance.stderr b/tests/ui/impl-trait/in-trait/variance.stderr
new file mode 100644
index 000000000..8cae5a92f
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/variance.stderr
@@ -0,0 +1,26 @@
+error: [o, *, *, o, o]
+  --> $DIR/variance.rs:9:44
+   |
+LL |     fn implicit_capture_early<'a: 'a>() -> impl Sized {}
+   |                                            ^^^^^^^^^^
+
+error: [o, *, *, o, o]
+  --> $DIR/variance.rs:13:44
+   |
+LL |     fn explicit_capture_early<'a: 'a>() -> impl Sized + Captures<'a> {}
+   |                                            ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: [o, *, o, o]
+  --> $DIR/variance.rs:15:48
+   |
+LL |     fn implicit_capture_late<'a>(_: &'a ()) -> impl Sized {}
+   |                                                ^^^^^^^^^^
+
+error: [o, *, o, o]
+  --> $DIR/variance.rs:17:48
+   |
+LL |     fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {}
+   |                                                ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 4 previous errors
+
diff --git a/tests/ui/impl-trait/issue-103181-2.rs b/tests/ui/impl-trait/issue-103181-2.rs
index 34deb98be..b43ac4507 100644
--- a/tests/ui/impl-trait/issue-103181-2.rs
+++ b/tests/ui/impl-trait/issue-103181-2.rs
@@ -24,8 +24,6 @@ where
     B: Send, // <- a second bound
 {
     normalize(broken_fut(), ());
-    //~^ ERROR: cannot check whether the hidden type of opaque type satisfies auto traits
-    //~| ERROR: cannot check whether the hidden type of opaque type satisfies auto traits
 }
 
 fn main() {}
diff --git a/tests/ui/impl-trait/issue-103181-2.stderr b/tests/ui/impl-trait/issue-103181-2.stderr
index cb5253ea6..5eb2dd918 100644
--- a/tests/ui/impl-trait/issue-103181-2.stderr
+++ b/tests/ui/impl-trait/issue-103181-2.stderr
@@ -4,61 +4,6 @@ error[E0425]: cannot find value `ident_error` in this scope
 LL |     ident_error;
    |     ^^^^^^^^^^^ not found in this scope
 
-error: cannot check whether the hidden type of opaque type satisfies auto traits
-  --> $DIR/issue-103181-2.rs:26:15
-   |
-LL |     normalize(broken_fut(), ());
-   |     --------- ^^^^^^^^^^^^
-   |     |
-   |     required by a bound introduced by this call
-   |
-note: opaque type is declared here
-  --> $DIR/issue-103181-2.rs:11:23
-   |
-LL | async fn broken_fut() {
-   |                       ^
-note: this item depends on auto traits of the hidden type, but may also be registering the hidden type. This is not supported right now. You can try moving the opaque type and the item that actually registers a hidden type into a new submodule
-  --> $DIR/issue-103181-2.rs:20:10
-   |
-LL | async fn iceice<A, B>()
-   |          ^^^^^^
-note: required for `impl Future<Output = ()>` to implement `SendFuture`
-  --> $DIR/issue-103181-2.rs:7:17
-   |
-LL | impl<Fut: Send> SendFuture for Fut {
-   |           ----  ^^^^^^^^^^     ^^^
-   |           |
-   |           unsatisfied trait bound introduced here
-note: required by a bound in `normalize`
-  --> $DIR/issue-103181-2.rs:18:19
-   |
-LL | fn normalize<Fut: SendFuture>(_: Fut, _: Fut::Output) {}
-   |                   ^^^^^^^^^^ required by this bound in `normalize`
-
-error: cannot check whether the hidden type of opaque type satisfies auto traits
-  --> $DIR/issue-103181-2.rs:26:5
-   |
-LL |     normalize(broken_fut(), ());
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: opaque type is declared here
-  --> $DIR/issue-103181-2.rs:11:23
-   |
-LL | async fn broken_fut() {
-   |                       ^
-note: this item depends on auto traits of the hidden type, but may also be registering the hidden type. This is not supported right now. You can try moving the opaque type and the item that actually registers a hidden type into a new submodule
-  --> $DIR/issue-103181-2.rs:20:10
-   |
-LL | async fn iceice<A, B>()
-   |          ^^^^^^
-note: required for `impl Future<Output = ()>` to implement `SendFuture`
-  --> $DIR/issue-103181-2.rs:7:17
-   |
-LL | impl<Fut: Send> SendFuture for Fut {
-   |           ----  ^^^^^^^^^^     ^^^
-   |           |
-   |           unsatisfied trait bound introduced here
-
-error: aborting due to 3 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0425`.
diff --git a/tests/ui/impl-trait/issue-108591.rs b/tests/ui/impl-trait/issue-108591.rs
index 6b9d14941..91ea2e9fb 100644
--- a/tests/ui/impl-trait/issue-108591.rs
+++ b/tests/ui/impl-trait/issue-108591.rs
@@ -13,7 +13,8 @@ impl MyTy<'_> {
     }
 }
 
-type Opaque<'a> = impl Sized;
+type Opaque2 = impl Sized;
+type Opaque<'a> = Opaque2;
 fn define<'a>() -> Opaque<'a> {}
 
 fn test<'a>() {
diff --git a/tests/ui/impl-trait/issue-108592.rs b/tests/ui/impl-trait/issue-108592.rs
index 58a0ed9bf..953fffc48 100644
--- a/tests/ui/impl-trait/issue-108592.rs
+++ b/tests/ui/impl-trait/issue-108592.rs
@@ -11,7 +11,8 @@ fn test_closure() {
     closure(&opaque());
 }
 
-type Opaque<'a> = impl Sized;
+type Opaque2 = impl Sized;
+type Opaque<'a> = Opaque2;
 fn define<'a>() -> Opaque<'a> {}
 
 fn test_tait(_: &Opaque<'_>) {
diff --git a/tests/ui/impl-trait/issue-55872-2.drop_tracking.stderr b/tests/ui/impl-trait/issue-55872-2.drop_tracking.stderr
deleted file mode 100644
index 477c964bd..000000000
--- a/tests/ui/impl-trait/issue-55872-2.drop_tracking.stderr
+++ /dev/null
@@ -1,8 +0,0 @@
-error: type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
-  --> $DIR/issue-55872-2.rs:17:9
-   |
-LL |         async {}
-   |         ^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/impl-trait/issue-55872-2.no_drop_tracking.stderr b/tests/ui/impl-trait/issue-55872-2.no_drop_tracking.stderr
deleted file mode 100644
index 477c964bd..000000000
--- a/tests/ui/impl-trait/issue-55872-2.no_drop_tracking.stderr
+++ /dev/null
@@ -1,8 +0,0 @@
-error: type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
-  --> $DIR/issue-55872-2.rs:17:9
-   |
-LL |         async {}
-   |         ^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/impl-trait/issue-55872-2.rs b/tests/ui/impl-trait/issue-55872-2.rs
index 7a5cb3b3d..8a96fdc5c 100644
--- a/tests/ui/impl-trait/issue-55872-2.rs
+++ b/tests/ui/impl-trait/issue-55872-2.rs
@@ -1,6 +1,3 @@
-// revisions: no_drop_tracking drop_tracking drop_tracking_mir
-// [drop_tracking] compile-flags: -Zdrop-tracking
-// [drop_tracking_mir] compile-flags: -Zdrop-tracking-mir
 // edition:2018
 
 #![feature(impl_trait_in_assoc_type)]
@@ -16,7 +13,7 @@ impl<S> Bar for S {
     fn foo<T>() -> Self::E {
         async {}
         //~^ ERROR type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
-        //[drop_tracking_mir]~^^ ERROR type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
+        //~| ERROR type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
     }
 }
 
diff --git a/tests/ui/impl-trait/issue-55872-2.drop_tracking_mir.stderr b/tests/ui/impl-trait/issue-55872-2.stderr
index c14bb5cc9..3e70f1cf8 100644
--- a/tests/ui/impl-trait/issue-55872-2.drop_tracking_mir.stderr
+++ b/tests/ui/impl-trait/issue-55872-2.stderr
@@ -1,11 +1,11 @@
 error: type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
-  --> $DIR/issue-55872-2.rs:17:9
+  --> $DIR/issue-55872-2.rs:14:9
    |
 LL |         async {}
    |         ^^^^^^^^
 
 error: type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias
-  --> $DIR/issue-55872-2.rs:17:9
+  --> $DIR/issue-55872-2.rs:14:9
    |
 LL |         async {}
    |         ^^^^^^^^
diff --git a/tests/ui/impl-trait/issue-55872-3.stderr b/tests/ui/impl-trait/issue-55872-3.stderr
index 827988974..b542b6141 100644
--- a/tests/ui/impl-trait/issue-55872-3.stderr
+++ b/tests/ui/impl-trait/issue-55872-3.stderr
@@ -1,8 +1,8 @@
-error[E0277]: the trait bound `[async block@$DIR/issue-55872-3.rs:15:9: 15:17]: Copy` is not satisfied
+error[E0277]: the trait bound `{async block@$DIR/issue-55872-3.rs:15:9: 15:17}: Copy` is not satisfied
   --> $DIR/issue-55872-3.rs:13:20
    |
 LL |     fn foo<T>() -> Self::E {
-   |                    ^^^^^^^ the trait `Copy` is not implemented for `[async block@$DIR/issue-55872-3.rs:15:9: 15:17]`
+   |                    ^^^^^^^ the trait `Copy` is not implemented for `{async block@$DIR/issue-55872-3.rs:15:9: 15:17}`
 
 error: aborting due to previous error
 
diff --git a/tests/ui/impl-trait/issue-86465.rs b/tests/ui/impl-trait/issue-86465.rs
index 8c7b41d73..a79bb6474 100644
--- a/tests/ui/impl-trait/issue-86465.rs
+++ b/tests/ui/impl-trait/issue-86465.rs
@@ -1,10 +1,6 @@
 #![feature(type_alias_impl_trait)]
 
-pub trait Captures<'a> {}
-
-impl<'a, T: ?Sized> Captures<'a> for T {}
-
-type X<'a, 'b> = impl std::fmt::Debug + Captures<'a> + Captures<'b>;
+type X<'a, 'b> = impl std::fmt::Debug;
 
 fn f<'t, 'u>(a: &'t u32, b: &'u u32) -> (X<'t, 'u>, X<'u, 't>) {
     (a, a)
diff --git a/tests/ui/impl-trait/issue-86465.stderr b/tests/ui/impl-trait/issue-86465.stderr
index b949b2b42..90d6904ed 100644
--- a/tests/ui/impl-trait/issue-86465.stderr
+++ b/tests/ui/impl-trait/issue-86465.stderr
@@ -1,5 +1,5 @@
 error: concrete type differs from previous defining opaque type use
-  --> $DIR/issue-86465.rs:10:5
+  --> $DIR/issue-86465.rs:6:5
    |
 LL |     (a, a)
    |     ^^^^^^
diff --git a/tests/ui/impl-trait/issue-99073.stderr b/tests/ui/impl-trait/issue-99073.stderr
index a8400080e..3c32f1794 100644
--- a/tests/ui/impl-trait/issue-99073.stderr
+++ b/tests/ui/impl-trait/issue-99073.stderr
@@ -10,7 +10,7 @@ error: concrete type differs from previous defining opaque type use
   --> $DIR/issue-99073.rs:6:13
    |
 LL |   move || f(fix(&f))
-   |             ^^^^^^^ expected `[closure@$DIR/issue-99073.rs:6:3: 6:10]`, got `G`
+   |             ^^^^^^^ expected `{closure@$DIR/issue-99073.rs:6:3: 6:10}`, got `G`
    |
 note: previous use here
   --> $DIR/issue-99073.rs:5:36
diff --git a/tests/ui/impl-trait/issues/issue-74282.stderr b/tests/ui/impl-trait/issues/issue-74282.stderr
index d43e9fee0..f8e85f7ae 100644
--- a/tests/ui/impl-trait/issues/issue-74282.stderr
+++ b/tests/ui/impl-trait/issues/issue-74282.stderr
@@ -14,7 +14,7 @@ LL | |     })
    | |_____^ expected opaque type, found closure
    |
    = note: expected opaque type `Closure`
-                  found closure `[closure@$DIR/issue-74282.rs:8:15: 8:17]`
+                  found closure `{closure@$DIR/issue-74282.rs:8:15: 8:17}`
    = note: no two closures, even if identical, have the same type
    = help: consider boxing your closure and/or using it as a trait object
 note: tuple struct defined here
diff --git a/tests/ui/impl-trait/issues/issue-78722-2.stderr b/tests/ui/impl-trait/issues/issue-78722-2.stderr
index 6db603e77..8817eb7d2 100644
--- a/tests/ui/impl-trait/issues/issue-78722-2.stderr
+++ b/tests/ui/impl-trait/issues/issue-78722-2.stderr
@@ -7,7 +7,7 @@ LL |         let f: F = async { 1 };
    = note: see issue #85368 <https://github.com/rust-lang/rust/issues/85368> for more information
    = help: add `#![feature(const_async_blocks)]` to the crate attributes to enable
 
-error[E0271]: expected `[async block@$DIR/issue-78722-2.rs:13:13: 13:21]` to be a future that resolves to `u8`, but it resolves to `()`
+error[E0271]: expected `{async block@$DIR/issue-78722-2.rs:13:13: 13:21}` to be a future that resolves to `u8`, but it resolves to `()`
   --> $DIR/issue-78722-2.rs:11:30
    |
 LL |         fn concrete_use() -> F {
diff --git a/tests/ui/impl-trait/issues/issue-78722.stderr b/tests/ui/impl-trait/issues/issue-78722.stderr
index 36340a0ba..5ad659697 100644
--- a/tests/ui/impl-trait/issues/issue-78722.stderr
+++ b/tests/ui/impl-trait/issues/issue-78722.stderr
@@ -7,7 +7,7 @@ LL |         let f: F = async { 1 };
    = note: see issue #85368 <https://github.com/rust-lang/rust/issues/85368> for more information
    = help: add `#![feature(const_async_blocks)]` to the crate attributes to enable
 
-error[E0271]: expected `[async block@$DIR/issue-78722.rs:10:13: 10:21]` to be a future that resolves to `u8`, but it resolves to `()`
+error[E0271]: expected `{async block@$DIR/issue-78722.rs:10:13: 10:21}` to be a future that resolves to `u8`, but it resolves to `()`
   --> $DIR/issue-78722.rs:8:30
    |
 LL |         fn concrete_use() -> F {
diff --git a/tests/ui/impl-trait/issues/issue-86800.stderr b/tests/ui/impl-trait/issues/issue-86800.stderr
index facab390d..8228f8ace 100644
--- a/tests/ui/impl-trait/issues/issue-86800.stderr
+++ b/tests/ui/impl-trait/issues/issue-86800.stderr
@@ -7,6 +7,6 @@ LL | type TransactionFuture<'__, O> = impl '__ + Future<Output = TransactionResu
 error: the compiler unexpectedly panicked. this is a bug.
 
 query stack during panic:
-#0 [type_of] computing type of `TransactionFuture::{opaque#0}`
-#1 [check_mod_item_types] checking item types in top-level module
+#0 [type_of_opaque] computing type of opaque `TransactionFuture::{opaque#0}`
+#1 [type_of] computing type of `TransactionFuture::{opaque#0}`
 end of query stack
diff --git a/tests/ui/impl-trait/must_outlive_least_region_or_bound.stderr b/tests/ui/impl-trait/must_outlive_least_region_or_bound.stderr
index 55e3cd950..33b48b1e9 100644
--- a/tests/ui/impl-trait/must_outlive_least_region_or_bound.stderr
+++ b/tests/ui/impl-trait/must_outlive_least_region_or_bound.stderr
@@ -104,7 +104,7 @@ error[E0700]: hidden type for `impl Fn(&'a u32)` captures lifetime that does not
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) {
    |                              --                             ---------------- opaque type defined here
    |                              |
-   |                              hidden type `[closure@$DIR/must_outlive_least_region_or_bound.rs:38:5: 38:13]` captures the lifetime `'b` as defined here
+   |                              hidden type `{closure@$DIR/must_outlive_least_region_or_bound.rs:38:5: 38:13}` captures the lifetime `'b` as defined here
 LL |     move |_| println!("{}", y)
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
diff --git a/tests/ui/impl-trait/nested-return-type2-tait2.stderr b/tests/ui/impl-trait/nested-return-type2-tait2.stderr
index b85bb5efd..125262b96 100644
--- a/tests/ui/impl-trait/nested-return-type2-tait2.stderr
+++ b/tests/ui/impl-trait/nested-return-type2-tait2.stderr
@@ -5,7 +5,7 @@ LL |     || 42
    |     ^^^^^ the trait `Duh` is not implemented for `Sendable`
    |
    = help: the trait `Duh` is implemented for `i32`
-note: required for `[closure@$DIR/nested-return-type2-tait2.rs:27:5: 27:7]` to implement `Trait`
+note: required for `{closure@$DIR/nested-return-type2-tait2.rs:27:5: 27:7}` to implement `Trait`
   --> $DIR/nested-return-type2-tait2.rs:14:31
    |
 LL | impl<R: Duh, F: FnMut() -> R> Trait for F {
diff --git a/tests/ui/impl-trait/nested-return-type2-tait3.stderr b/tests/ui/impl-trait/nested-return-type2-tait3.stderr
index 19fd3c134..c2332b6e4 100644
--- a/tests/ui/impl-trait/nested-return-type2-tait3.stderr
+++ b/tests/ui/impl-trait/nested-return-type2-tait3.stderr
@@ -5,7 +5,7 @@ LL |     || 42
    |     ^^^^^ the trait `Duh` is not implemented for `impl Send`
    |
    = help: the trait `Duh` is implemented for `i32`
-note: required for `[closure@$DIR/nested-return-type2-tait3.rs:26:5: 26:7]` to implement `Trait`
+note: required for `{closure@$DIR/nested-return-type2-tait3.rs:26:5: 26:7}` to implement `Trait`
   --> $DIR/nested-return-type2-tait3.rs:14:31
    |
 LL | impl<R: Duh, F: FnMut() -> R> Trait for F {
diff --git a/tests/ui/impl-trait/nested-return-type4.stderr b/tests/ui/impl-trait/nested-return-type4.stderr
index 907822ebb..a1e2d227f 100644
--- a/tests/ui/impl-trait/nested-return-type4.stderr
+++ b/tests/ui/impl-trait/nested-return-type4.stderr
@@ -4,7 +4,7 @@ error[E0700]: hidden type for `impl Future<Output = impl Sized>` captures lifeti
 LL | fn test<'s: 's>(s: &'s str) -> impl std::future::Future<Output = impl Sized> {
    |         --                     --------------------------------------------- opaque type defined here
    |         |
-   |         hidden type `[async block@$DIR/nested-return-type4.rs:4:5: 4:31]` captures the lifetime `'s` as defined here
+   |         hidden type `{async block@$DIR/nested-return-type4.rs:4:5: 4:31}` captures the lifetime `'s` as defined here
 LL |     async move { let _s = s; }
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
diff --git a/tests/ui/impl-trait/normalize-tait-in-const.stderr b/tests/ui/impl-trait/normalize-tait-in-const.stderr
index 5fbba9a85..ada8fd7fa 100644
--- a/tests/ui/impl-trait/normalize-tait-in-const.stderr
+++ b/tests/ui/impl-trait/normalize-tait-in-const.stderr
@@ -1,25 +1,8 @@
-error[E0015]: cannot call non-const closure in constant functions
-  --> $DIR/normalize-tait-in-const.rs:26:5
-   |
-LL |     fun(filter_positive());
-   |     ^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
-help: consider further restricting this bound
-   |
-LL | const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct + ~const std::ops::Fn<(&Alias<'_>,)>>(fun: F) {
-   |                                                                              ++++++++++++++++++++++++++++++++++++
-
-error[E0493]: destructor of `F` cannot be evaluated at compile-time
-  --> $DIR/normalize-tait-in-const.rs:25:79
+error: ~const can only be applied to `#[const_trait]` traits
+  --> $DIR/normalize-tait-in-const.rs:25:42
    |
 LL | const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
-   |                                                                               ^^^ the destructor for this type cannot be evaluated in constant functions
-LL |     fun(filter_positive());
-LL | }
-   | - value is dropped here
+   |                                          ^^^^^^^^^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
-Some errors have detailed explanations: E0015, E0493.
-For more information about an error, try `rustc --explain E0015`.
diff --git a/tests/ui/impl-trait/recursive-generator.rs b/tests/ui/impl-trait/recursive-generator.rs
index e876f0fb4..000af70c4 100644
--- a/tests/ui/impl-trait/recursive-generator.rs
+++ b/tests/ui/impl-trait/recursive-generator.rs
@@ -7,7 +7,6 @@ fn foo() -> impl Generator<Yield = (), Return = ()> {
     //~| NOTE recursive opaque type
     //~| NOTE in this expansion of desugaring of
     || {
-    //~^ NOTE returning here
         let mut gen = Box::pin(foo());
         //~^ NOTE generator captures itself here
         let mut r = gen.as_mut().resume(());
diff --git a/tests/ui/impl-trait/recursive-generator.stderr b/tests/ui/impl-trait/recursive-generator.stderr
index e23fd4b4a..86e193d95 100644
--- a/tests/ui/impl-trait/recursive-generator.stderr
+++ b/tests/ui/impl-trait/recursive-generator.stderr
@@ -1,18 +1,11 @@
 error[E0720]: cannot resolve opaque type
   --> $DIR/recursive-generator.rs:5:13
    |
-LL |   fn foo() -> impl Generator<Yield = (), Return = ()> {
-   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ recursive opaque type
+LL | fn foo() -> impl Generator<Yield = (), Return = ()> {
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ recursive opaque type
 ...
-LL | /     || {
-LL | |
-LL | |         let mut gen = Box::pin(foo());
-   | |             ------- generator captures itself here
-LL | |
-...  |
-LL | |         }
-LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-generator.rs:9:5: 9:7]`
+LL |         let mut gen = Box::pin(foo());
+   |             ------- generator captures itself here
 
 error: aborting due to previous error
 
diff --git a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.drop_tracking.stderr b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.drop_tracking.stderr
deleted file mode 100644
index 43118ae38..000000000
--- a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.drop_tracking.stderr
+++ /dev/null
@@ -1,152 +0,0 @@
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:11:22
-   |
-LL | fn option(i: i32) -> impl Sized {
-   |                      ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     if i < 0 { None } else { Some((option(i - 1), i)) }
-   |                ----          ------------------------ returning here with type `Option<(impl Sized, i32)>`
-   |                |
-   |                returning here with type `Option<(impl Sized, i32)>`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:16:15
-   |
-LL | fn tuple() -> impl Sized {
-   |               ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     (tuple(),)
-   |     ---------- returning here with type `(impl Sized,)`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:21:15
-   |
-LL | fn array() -> impl Sized {
-   |               ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     [array()]
-   |     --------- returning here with type `[impl Sized; 1]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:26:13
-   |
-LL | fn ptr() -> impl Sized {
-   |             ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     &ptr() as *const _
-   |     ------------------ returning here with type `*const impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:31:16
-   |
-LL | fn fn_ptr() -> impl Sized {
-   |                ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     fn_ptr as fn() -> _
-   |     ------------------- returning here with type `fn() -> impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:36:25
-   |
-LL |   fn closure_capture() -> impl Sized {
-   |                           ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         x;
-   | |         - closure captures itself here
-LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:39:5: 39:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:44:29
-   |
-LL |   fn closure_ref_capture() -> impl Sized {
-   |                               ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         &x;
-   | |          - closure captures itself here
-LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:47:5: 47:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:52:21
-   |
-LL | fn closure_sig() -> impl Sized {
-   |                     ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     || closure_sig()
-   |     ---------------- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:54:5: 54:7]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:57:23
-   |
-LL | fn generator_sig() -> impl Sized {
-   |                       ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     || generator_sig()
-   |     ------------------ returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:59:5: 59:7]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:62:27
-   |
-LL |   fn generator_capture() -> impl Sized {
-   |                             ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         yield;
-LL | |         x;
-   | |         - generator captures itself here
-LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-impl-trait-type-indirect.rs:65:5: 65:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:71:35
-   |
-LL | fn substs_change<T: 'static>() -> impl Sized {
-   |                                   ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     (substs_change::<&T>(),)
-   |     ------------------------ returning here with type `(impl Sized,)`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:76:24
-   |
-LL |   fn generator_hold() -> impl Sized {
-   |                          ^^^^^^^^^^ recursive opaque type
-LL |
-LL | /     move || {
-LL | |         let x = generator_hold();
-   | |             - generator captures itself here
-LL | |         yield;
-LL | |         x;
-LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-impl-trait-type-indirect.rs:78:5: 78:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:90:26
-   |
-LL | fn mutual_recursion() -> impl Sync {
-   |                          ^^^^^^^^^ recursive opaque type
-LL |
-LL |     mutual_recursion_b()
-   |     -------------------- returning here with type `impl Sized`
-...
-LL | fn mutual_recursion_b() -> impl Sized {
-   |                            ---------- returning this opaque type `impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:95:28
-   |
-LL | fn mutual_recursion() -> impl Sync {
-   |                          --------- returning this opaque type `impl Sync`
-...
-LL | fn mutual_recursion_b() -> impl Sized {
-   |                            ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     mutual_recursion()
-   |     ------------------ returning here with type `impl Sync`
-
-error: aborting due to 14 previous errors
-
-For more information about this error, try `rustc --explain E0720`.
diff --git a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.no_drop_tracking.stderr b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.no_drop_tracking.stderr
deleted file mode 100644
index 43118ae38..000000000
--- a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.no_drop_tracking.stderr
+++ /dev/null
@@ -1,152 +0,0 @@
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:11:22
-   |
-LL | fn option(i: i32) -> impl Sized {
-   |                      ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     if i < 0 { None } else { Some((option(i - 1), i)) }
-   |                ----          ------------------------ returning here with type `Option<(impl Sized, i32)>`
-   |                |
-   |                returning here with type `Option<(impl Sized, i32)>`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:16:15
-   |
-LL | fn tuple() -> impl Sized {
-   |               ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     (tuple(),)
-   |     ---------- returning here with type `(impl Sized,)`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:21:15
-   |
-LL | fn array() -> impl Sized {
-   |               ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     [array()]
-   |     --------- returning here with type `[impl Sized; 1]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:26:13
-   |
-LL | fn ptr() -> impl Sized {
-   |             ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     &ptr() as *const _
-   |     ------------------ returning here with type `*const impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:31:16
-   |
-LL | fn fn_ptr() -> impl Sized {
-   |                ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     fn_ptr as fn() -> _
-   |     ------------------- returning here with type `fn() -> impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:36:25
-   |
-LL |   fn closure_capture() -> impl Sized {
-   |                           ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         x;
-   | |         - closure captures itself here
-LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:39:5: 39:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:44:29
-   |
-LL |   fn closure_ref_capture() -> impl Sized {
-   |                               ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         &x;
-   | |          - closure captures itself here
-LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:47:5: 47:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:52:21
-   |
-LL | fn closure_sig() -> impl Sized {
-   |                     ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     || closure_sig()
-   |     ---------------- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:54:5: 54:7]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:57:23
-   |
-LL | fn generator_sig() -> impl Sized {
-   |                       ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     || generator_sig()
-   |     ------------------ returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:59:5: 59:7]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:62:27
-   |
-LL |   fn generator_capture() -> impl Sized {
-   |                             ^^^^^^^^^^ recursive opaque type
-...
-LL | /     move || {
-LL | |         yield;
-LL | |         x;
-   | |         - generator captures itself here
-LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-impl-trait-type-indirect.rs:65:5: 65:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:71:35
-   |
-LL | fn substs_change<T: 'static>() -> impl Sized {
-   |                                   ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     (substs_change::<&T>(),)
-   |     ------------------------ returning here with type `(impl Sized,)`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:76:24
-   |
-LL |   fn generator_hold() -> impl Sized {
-   |                          ^^^^^^^^^^ recursive opaque type
-LL |
-LL | /     move || {
-LL | |         let x = generator_hold();
-   | |             - generator captures itself here
-LL | |         yield;
-LL | |         x;
-LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-impl-trait-type-indirect.rs:78:5: 78:12]`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:90:26
-   |
-LL | fn mutual_recursion() -> impl Sync {
-   |                          ^^^^^^^^^ recursive opaque type
-LL |
-LL |     mutual_recursion_b()
-   |     -------------------- returning here with type `impl Sized`
-...
-LL | fn mutual_recursion_b() -> impl Sized {
-   |                            ---------- returning this opaque type `impl Sized`
-
-error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:95:28
-   |
-LL | fn mutual_recursion() -> impl Sync {
-   |                          --------- returning this opaque type `impl Sync`
-...
-LL | fn mutual_recursion_b() -> impl Sized {
-   |                            ^^^^^^^^^^ recursive opaque type
-LL |
-LL |     mutual_recursion()
-   |     ------------------ returning here with type `impl Sync`
-
-error: aborting due to 14 previous errors
-
-For more information about this error, try `rustc --explain E0720`.
diff --git a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.rs b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.rs
index 630372e13..ffc0cd9d1 100644
--- a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.rs
+++ b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.rs
@@ -1,7 +1,3 @@
-// revisions: no_drop_tracking drop_tracking drop_tracking_mir
-// [drop_tracking] compile-flags: -Zdrop-tracking
-// [drop_tracking_mir] compile-flags: -Zdrop-tracking-mir
-
 // Test that impl trait does not allow creating recursive types that are
 // otherwise forbidden.
 
diff --git a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.drop_tracking_mir.stderr b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.stderr
index 9c67f17e9..1d919fb52 100644
--- a/tests/ui/impl-trait/recursive-impl-trait-type-indirect.drop_tracking_mir.stderr
+++ b/tests/ui/impl-trait/recursive-impl-trait-type-indirect.stderr
@@ -1,5 +1,5 @@
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:11:22
+  --> $DIR/recursive-impl-trait-type-indirect.rs:7:22
    |
 LL | fn option(i: i32) -> impl Sized {
    |                      ^^^^^^^^^^ recursive opaque type
@@ -10,7 +10,7 @@ LL |     if i < 0 { None } else { Some((option(i - 1), i)) }
    |                returning here with type `Option<(impl Sized, i32)>`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:16:15
+  --> $DIR/recursive-impl-trait-type-indirect.rs:12:15
    |
 LL | fn tuple() -> impl Sized {
    |               ^^^^^^^^^^ recursive opaque type
@@ -19,7 +19,7 @@ LL |     (tuple(),)
    |     ---------- returning here with type `(impl Sized,)`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:21:15
+  --> $DIR/recursive-impl-trait-type-indirect.rs:17:15
    |
 LL | fn array() -> impl Sized {
    |               ^^^^^^^^^^ recursive opaque type
@@ -28,7 +28,7 @@ LL |     [array()]
    |     --------- returning here with type `[impl Sized; 1]`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:26:13
+  --> $DIR/recursive-impl-trait-type-indirect.rs:22:13
    |
 LL | fn ptr() -> impl Sized {
    |             ^^^^^^^^^^ recursive opaque type
@@ -37,7 +37,7 @@ LL |     &ptr() as *const _
    |     ------------------ returning here with type `*const impl Sized`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:31:16
+  --> $DIR/recursive-impl-trait-type-indirect.rs:27:16
    |
 LL | fn fn_ptr() -> impl Sized {
    |                ^^^^^^^^^^ recursive opaque type
@@ -46,7 +46,7 @@ LL |     fn_ptr as fn() -> _
    |     ------------------- returning here with type `fn() -> impl Sized`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:36:25
+  --> $DIR/recursive-impl-trait-type-indirect.rs:32:25
    |
 LL |   fn closure_capture() -> impl Sized {
    |                           ^^^^^^^^^^ recursive opaque type
@@ -55,10 +55,10 @@ LL | /     move || {
 LL | |         x;
    | |         - closure captures itself here
 LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:39:5: 39:12]`
+   | |_____- returning here with type `{closure@$DIR/recursive-impl-trait-type-indirect.rs:35:5: 35:12}`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:44:29
+  --> $DIR/recursive-impl-trait-type-indirect.rs:40:29
    |
 LL |   fn closure_ref_capture() -> impl Sized {
    |                               ^^^^^^^^^^ recursive opaque type
@@ -67,28 +67,28 @@ LL | /     move || {
 LL | |         &x;
    | |          - closure captures itself here
 LL | |     }
-   | |_____- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:47:5: 47:12]`
+   | |_____- returning here with type `{closure@$DIR/recursive-impl-trait-type-indirect.rs:43:5: 43:12}`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:52:21
+  --> $DIR/recursive-impl-trait-type-indirect.rs:48:21
    |
 LL | fn closure_sig() -> impl Sized {
    |                     ^^^^^^^^^^ recursive opaque type
 LL |
 LL |     || closure_sig()
-   |     ---------------- returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:54:5: 54:7]`
+   |     ---------------- returning here with type `{closure@$DIR/recursive-impl-trait-type-indirect.rs:50:5: 50:7}`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:57:23
+  --> $DIR/recursive-impl-trait-type-indirect.rs:53:23
    |
 LL | fn generator_sig() -> impl Sized {
    |                       ^^^^^^^^^^ recursive opaque type
 LL |
 LL |     || generator_sig()
-   |     ------------------ returning here with type `[closure@$DIR/recursive-impl-trait-type-indirect.rs:59:5: 59:7]`
+   |     ------------------ returning here with type `{closure@$DIR/recursive-impl-trait-type-indirect.rs:55:5: 55:7}`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:62:27
+  --> $DIR/recursive-impl-trait-type-indirect.rs:58:27
    |
 LL |   fn generator_capture() -> impl Sized {
    |                             ^^^^^^^^^^ recursive opaque type
@@ -98,10 +98,10 @@ LL | |         yield;
 LL | |         x;
    | |         - generator captures itself here
 LL | |     }
-   | |_____- returning here with type `[generator@$DIR/recursive-impl-trait-type-indirect.rs:65:5: 65:12]`
+   | |_____- returning here with type `{generator@$DIR/recursive-impl-trait-type-indirect.rs:61:5: 61:12}`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:71:35
+  --> $DIR/recursive-impl-trait-type-indirect.rs:67:35
    |
 LL | fn substs_change<T: 'static>() -> impl Sized {
    |                                   ^^^^^^^^^^ recursive opaque type
@@ -110,7 +110,7 @@ LL |     (substs_change::<&T>(),)
    |     ------------------------ returning here with type `(impl Sized,)`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:76:24
+  --> $DIR/recursive-impl-trait-type-indirect.rs:72:24
    |
 LL | fn generator_hold() -> impl Sized {
    |                        ^^^^^^^^^^ recursive opaque type
@@ -119,7 +119,7 @@ LL |         let x = generator_hold();
    |             - generator captures itself here
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:90:26
+  --> $DIR/recursive-impl-trait-type-indirect.rs:86:26
    |
 LL | fn mutual_recursion() -> impl Sync {
    |                          ^^^^^^^^^ recursive opaque type
@@ -131,7 +131,7 @@ LL | fn mutual_recursion_b() -> impl Sized {
    |                            ---------- returning this opaque type `impl Sized`
 
 error[E0720]: cannot resolve opaque type
-  --> $DIR/recursive-impl-trait-type-indirect.rs:95:28
+  --> $DIR/recursive-impl-trait-type-indirect.rs:91:28
    |
 LL | fn mutual_recursion() -> impl Sync {
    |                          --------- returning this opaque type `impl Sync`
diff --git a/tests/ui/impl-trait/static-return-lifetime-infered.stderr b/tests/ui/impl-trait/static-return-lifetime-infered.stderr
index 488cb821c..4be244068 100644
--- a/tests/ui/impl-trait/static-return-lifetime-infered.stderr
+++ b/tests/ui/impl-trait/static-return-lifetime-infered.stderr
@@ -4,7 +4,7 @@ error[E0700]: hidden type for `impl Iterator<Item = u32>` captures lifetime that
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
    |                         -----     ----------------------- opaque type defined here
    |                         |
-   |                         hidden type `Map<std::slice::Iter<'_, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:7:27: 7:30]>` captures the anonymous lifetime defined here
+   |                         hidden type `Map<std::slice::Iter<'_, (u32, u32)>, {closure@$DIR/static-return-lifetime-infered.rs:7:27: 7:30}>` captures the anonymous lifetime defined here
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
@@ -19,7 +19,7 @@ error[E0700]: hidden type for `impl Iterator<Item = u32>` captures lifetime that
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                    --               ----------------------- opaque type defined here
    |                    |
-   |                    hidden type `Map<std::slice::Iter<'a, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:11:27: 11:30]>` captures the lifetime `'a` as defined here
+   |                    hidden type `Map<std::slice::Iter<'a, (u32, u32)>, {closure@$DIR/static-return-lifetime-infered.rs:11:27: 11:30}>` captures the lifetime `'a` as defined here
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
diff --git a/tests/ui/impl-trait/variance.rs b/tests/ui/impl-trait/variance.rs
new file mode 100644
index 000000000..d6212f8f3
--- /dev/null
+++ b/tests/ui/impl-trait/variance.rs
@@ -0,0 +1,16 @@
+#![feature(rustc_attrs)]
+#![allow(internal_features)]
+#![rustc_variance_of_opaques]
+
+trait Captures<'a> {}
+impl<T> Captures<'_> for T {}
+
+fn not_captured_early<'a: 'a>() -> impl Sized {} //~ [*]
+
+fn captured_early<'a: 'a>() -> impl Sized + Captures<'a> {} //~ [*, o]
+
+fn not_captured_late<'a>(_: &'a ()) -> impl Sized {} //~ []
+
+fn captured_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {} //~ [o]
+
+fn main() {}
diff --git a/tests/ui/impl-trait/variance.stderr b/tests/ui/impl-trait/variance.stderr
new file mode 100644
index 000000000..644736754
--- /dev/null
+++ b/tests/ui/impl-trait/variance.stderr
@@ -0,0 +1,26 @@
+error: [*]
+  --> $DIR/variance.rs:8:36
+   |
+LL | fn not_captured_early<'a: 'a>() -> impl Sized {}
+   |                                    ^^^^^^^^^^
+
+error: [*, o]
+  --> $DIR/variance.rs:10:32
+   |
+LL | fn captured_early<'a: 'a>() -> impl Sized + Captures<'a> {}
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: []
+  --> $DIR/variance.rs:12:40
+   |
+LL | fn not_captured_late<'a>(_: &'a ()) -> impl Sized {}
+   |                                        ^^^^^^^^^^
+
+error: [o]
+  --> $DIR/variance.rs:14:36
+   |
+LL | fn captured_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {}
+   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 4 previous errors
+