Auto merge of #99506 - Dylan-DPC:rollup-q3msucx, r=Dylan-DPC

Rollup of 7 pull requests

Successful merges:

 - #98101 (stdlib support for Apple WatchOS)
 - #99345 (Do not allow typeck children items to constrain outer RPITs)
 - #99383 (Formalize defining_use_anchor)
 - #99436 (Add flag to configure `noalias` on `Box<T>`)
 - #99483 (Fix a numerical underflow in tuple wrap suggestion)
 - #99485 (Stop injecting `#[allow(unused_qualifications)]` in generated `derive` implementations)
 - #99486 (Refactor: remove a string comparison between types in `check_str_addition`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

22 files changed, 241 insertions, 134 deletions

diff --git a/src/test/codegen/noalias-box-off.rs b/src/test/codegen/noalias-box-off.rs
new file mode 100644
index 00000000000..afd17c7c160
--- /dev/null
+++ b/src/test/codegen/noalias-box-off.rs
@@ -0,0 +1,8 @@
+// compile-flags: -O -Z box-noalias=no
+
+#![crate_type = "lib"]
+
+// CHECK-LABEL: @box_should_not_have_noalias_if_disabled(
+// CHECK-NOT: noalias
+#[no_mangle]
+pub fn box_should_not_have_noalias_if_disabled(_b: Box<u8>) {}
diff --git a/src/test/codegen/noalias-box.rs b/src/test/codegen/noalias-box.rs
new file mode 100644
index 00000000000..a3d1f093d8b
--- /dev/null
+++ b/src/test/codegen/noalias-box.rs
@@ -0,0 +1,8 @@
+// compile-flags: -O
+
+#![crate_type = "lib"]
+
+// CHECK-LABEL: @box_should_have_noalias_by_default(
+// CHECK: noalias
+#[no_mangle]
+pub fn box_should_have_noalias_by_default(_b: Box<u8>) {}
diff --git a/src/test/rustdoc-ui/z-help.stdout b/src/test/rustdoc-ui/z-help.stdout
index 7296b35788a..6f5248f5b18 100644
--- a/src/test/rustdoc-ui/z-help.stdout
+++ b/src/test/rustdoc-ui/z-help.stdout
@@ -4,6 +4,7 @@
     -Z                            asm-comments=val -- generate comments into the assembly (may change behavior) (default: no)
     -Z                       assert-incr-state=val -- assert that the incremental cache is in given state: either `loaded` or `not-loaded`.
     -Z                      binary-dep-depinfo=val -- include artifacts (sysroot, crate dependencies) used during compilation in dep-info (default: no)
+    -Z                             box-noalias=val -- emit noalias metadata for box (default: yes)
     -Z                       branch-protection=val -- set options for branch target identification and pointer authentication on AArch64
     -Z                           cf-protection=val -- instrument control-flow architecture protection
     -Z               cgu-partitioning-strategy=val -- the codegen unit partitioning strategy to use
diff --git a/src/test/ui/argument-suggestions/issue-99482.rs b/src/test/ui/argument-suggestions/issue-99482.rs
new file mode 100644
index 00000000000..731b863069b
--- /dev/null
+++ b/src/test/ui/argument-suggestions/issue-99482.rs
@@ -0,0 +1,5 @@
+fn main() {
+    let f = |_: (), f: fn()| f;
+    let _f = f(main);
+    //~^ ERROR this function takes 2 arguments but 1 argument was supplied
+}
diff --git a/src/test/ui/argument-suggestions/issue-99482.stderr b/src/test/ui/argument-suggestions/issue-99482.stderr
new file mode 100644
index 00000000000..bc005e82a2c
--- /dev/null
+++ b/src/test/ui/argument-suggestions/issue-99482.stderr
@@ -0,0 +1,19 @@
+error[E0057]: this function takes 2 arguments but 1 argument was supplied
+  --> $DIR/issue-99482.rs:3:14
+   |
+LL |     let _f = f(main);
+   |              ^ ---- an argument of type `()` is missing
+   |
+note: closure defined here
+  --> $DIR/issue-99482.rs:2:13
+   |
+LL |     let f = |_: (), f: fn()| f;
+   |             ^^^^^^^^^^^^^^^^
+help: provide the argument
+   |
+LL |     let _f = f((), main);
+   |              ~~~~~~~~~~~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0057`.
diff --git a/src/test/ui/deriving/deriving-all-codegen.stdout b/src/test/ui/deriving/deriving-all-codegen.stdout
index 542911537be..21fe663f067 100644
--- a/src/test/ui/deriving/deriving-all-codegen.stdout
+++ b/src/test/ui/deriving/deriving-all-codegen.stdout
@@ -25,42 +25,35 @@ extern crate std;
 // Empty struct.
 struct Empty;
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Empty {
     #[inline]
     fn clone(&self) -> Empty { *self }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Empty { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Empty {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         ::core::fmt::Formatter::write_str(f, "Empty")
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Empty {
     #[inline]
     fn default() -> Empty { Empty {} }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Empty {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
 }
 impl ::core::marker::StructuralPartialEq for Empty {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Empty {
     #[inline]
     fn eq(&self, other: &Empty) -> bool { true }
 }
 impl ::core::marker::StructuralEq for Empty {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Empty {
     #[inline]
     #[doc(hidden)]
@@ -68,7 +61,6 @@ impl ::core::cmp::Eq for Empty {
     fn assert_receiver_is_total_eq(&self) -> () {}
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Empty {
     #[inline]
     fn partial_cmp(&self, other: &Empty)
@@ -77,7 +69,6 @@ impl ::core::cmp::PartialOrd for Empty {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Empty {
     #[inline]
     fn cmp(&self, other: &Empty) -> ::core::cmp::Ordering {
@@ -91,7 +82,6 @@ struct Point {
     y: u32,
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Point {
     #[inline]
     fn clone(&self) -> Point {
@@ -100,10 +90,8 @@ impl ::core::clone::Clone for Point {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Point { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Point {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         ::core::fmt::Formatter::debug_struct_field2_finish(f, "Point", "x",
@@ -111,7 +99,6 @@ impl ::core::fmt::Debug for Point {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Point {
     #[inline]
     fn default() -> Point {
@@ -122,7 +109,6 @@ impl ::core::default::Default for Point {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Point {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         ::core::hash::Hash::hash(&self.x, state);
@@ -131,7 +117,6 @@ impl ::core::hash::Hash for Point {
 }
 impl ::core::marker::StructuralPartialEq for Point {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Point {
     #[inline]
     fn eq(&self, other: &Point) -> bool {
@@ -144,7 +129,6 @@ impl ::core::cmp::PartialEq for Point {
 }
 impl ::core::marker::StructuralEq for Point {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Point {
     #[inline]
     #[doc(hidden)]
@@ -154,7 +138,6 @@ impl ::core::cmp::Eq for Point {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Point {
     #[inline]
     fn partial_cmp(&self, other: &Point)
@@ -167,7 +150,6 @@ impl ::core::cmp::PartialOrd for Point {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Point {
     #[inline]
     fn cmp(&self, other: &Point) -> ::core::cmp::Ordering {
@@ -191,7 +173,6 @@ struct Big {
     b8: u32,
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Big {
     #[inline]
     fn clone(&self) -> Big {
@@ -208,7 +189,6 @@ impl ::core::clone::Clone for Big {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Big {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         let names: &'static _ =
@@ -221,7 +201,6 @@ impl ::core::fmt::Debug for Big {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Big {
     #[inline]
     fn default() -> Big {
@@ -238,7 +217,6 @@ impl ::core::default::Default for Big {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Big {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         ::core::hash::Hash::hash(&self.b1, state);
@@ -253,7 +231,6 @@ impl ::core::hash::Hash for Big {
 }
 impl ::core::marker::StructuralPartialEq for Big {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Big {
     #[inline]
     fn eq(&self, other: &Big) -> bool {
@@ -272,7 +249,6 @@ impl ::core::cmp::PartialEq for Big {
 }
 impl ::core::marker::StructuralEq for Big {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Big {
     #[inline]
     #[doc(hidden)]
@@ -282,7 +258,6 @@ impl ::core::cmp::Eq for Big {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Big {
     #[inline]
     fn partial_cmp(&self, other: &Big)
@@ -331,7 +306,6 @@ impl ::core::cmp::PartialOrd for Big {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Big {
     #[inline]
     fn cmp(&self, other: &Big) -> ::core::cmp::Ordering {
@@ -370,7 +344,6 @@ impl ::core::cmp::Ord for Big {
 // A struct with an unsized field. Some derives are not usable in this case.
 struct Unsized([u32]);
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Unsized {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         ::core::fmt::Formatter::debug_tuple_field1_finish(f, "Unsized",
@@ -378,7 +351,6 @@ impl ::core::fmt::Debug for Unsized {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Unsized {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         ::core::hash::Hash::hash(&self.0, state)
@@ -386,7 +358,6 @@ impl ::core::hash::Hash for Unsized {
 }
 impl ::core::marker::StructuralPartialEq for Unsized {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Unsized {
     #[inline]
     fn eq(&self, other: &Unsized) -> bool { self.0 == other.0 }
@@ -395,7 +366,6 @@ impl ::core::cmp::PartialEq for Unsized {
 }
 impl ::core::marker::StructuralEq for Unsized {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Unsized {
     #[inline]
     #[doc(hidden)]
@@ -405,7 +375,6 @@ impl ::core::cmp::Eq for Unsized {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Unsized {
     #[inline]
     fn partial_cmp(&self, other: &Unsized)
@@ -414,7 +383,6 @@ impl ::core::cmp::PartialOrd for Unsized {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Unsized {
     #[inline]
     fn cmp(&self, other: &Unsized) -> ::core::cmp::Ordering {
@@ -426,7 +394,6 @@ impl ::core::cmp::Ord for Unsized {
 #[repr(packed)]
 struct PackedCopy(u32);
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for PackedCopy {
     #[inline]
     fn clone(&self) -> PackedCopy {
@@ -435,10 +402,8 @@ impl ::core::clone::Clone for PackedCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for PackedCopy { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for PackedCopy {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         ::core::fmt::Formatter::debug_tuple_field1_finish(f, "PackedCopy",
@@ -446,7 +411,6 @@ impl ::core::fmt::Debug for PackedCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for PackedCopy {
     #[inline]
     fn default() -> PackedCopy {
@@ -454,7 +418,6 @@ impl ::core::default::Default for PackedCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for PackedCopy {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         ::core::hash::Hash::hash(&{ self.0 }, state)
@@ -462,7 +425,6 @@ impl ::core::hash::Hash for PackedCopy {
 }
 impl ::core::marker::StructuralPartialEq for PackedCopy {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for PackedCopy {
     #[inline]
     fn eq(&self, other: &PackedCopy) -> bool { { self.0 } == { other.0 } }
@@ -471,7 +433,6 @@ impl ::core::cmp::PartialEq for PackedCopy {
 }
 impl ::core::marker::StructuralEq for PackedCopy {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for PackedCopy {
     #[inline]
     #[doc(hidden)]
@@ -481,7 +442,6 @@ impl ::core::cmp::Eq for PackedCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for PackedCopy {
     #[inline]
     fn partial_cmp(&self, other: &PackedCopy)
@@ -490,7 +450,6 @@ impl ::core::cmp::PartialOrd for PackedCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for PackedCopy {
     #[inline]
     fn cmp(&self, other: &PackedCopy) -> ::core::cmp::Ordering {
@@ -506,7 +465,6 @@ impl ::core::cmp::Ord for PackedCopy {
 #[repr(packed)]
 struct PackedNonCopy(u8);
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for PackedNonCopy {
     #[inline]
     fn clone(&self) -> PackedNonCopy {
@@ -515,7 +473,6 @@ impl ::core::clone::Clone for PackedNonCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for PackedNonCopy {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         let Self(ref __self_0_0) = *self;
@@ -524,7 +481,6 @@ impl ::core::fmt::Debug for PackedNonCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for PackedNonCopy {
     #[inline]
     fn default() -> PackedNonCopy {
@@ -532,7 +488,6 @@ impl ::core::default::Default for PackedNonCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for PackedNonCopy {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         let Self(ref __self_0_0) = *self;
@@ -541,7 +496,6 @@ impl ::core::hash::Hash for PackedNonCopy {
 }
 impl ::core::marker::StructuralPartialEq for PackedNonCopy {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for PackedNonCopy {
     #[inline]
     fn eq(&self, other: &PackedNonCopy) -> bool {
@@ -558,7 +512,6 @@ impl ::core::cmp::PartialEq for PackedNonCopy {
 }
 impl ::core::marker::StructuralEq for PackedNonCopy {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for PackedNonCopy {
     #[inline]
     #[doc(hidden)]
@@ -568,7 +521,6 @@ impl ::core::cmp::Eq for PackedNonCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for PackedNonCopy {
     #[inline]
     fn partial_cmp(&self, other: &PackedNonCopy)
@@ -579,7 +531,6 @@ impl ::core::cmp::PartialOrd for PackedNonCopy {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for PackedNonCopy {
     #[inline]
     fn cmp(&self, other: &PackedNonCopy) -> ::core::cmp::Ordering {
@@ -592,23 +543,19 @@ impl ::core::cmp::Ord for PackedNonCopy {
 // An empty enum.
 enum Enum0 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Enum0 {
     #[inline]
     fn clone(&self) -> Enum0 { *self }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Enum0 { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Enum0 {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         unsafe { ::core::intrinsics::unreachable() }
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Enum0 {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         unsafe { ::core::intrinsics::unreachable() }
@@ -616,7 +563,6 @@ impl ::core::hash::Hash for Enum0 {
 }
 impl ::core::marker::StructuralPartialEq for Enum0 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Enum0 {
     #[inline]
     fn eq(&self, other: &Enum0) -> bool {
@@ -625,7 +571,6 @@ impl ::core::cmp::PartialEq for Enum0 {
 }
 impl ::core::marker::StructuralEq for Enum0 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Enum0 {
     #[inline]
     #[doc(hidden)]
@@ -633,7 +578,6 @@ impl ::core::cmp::Eq for Enum0 {
     fn assert_receiver_is_total_eq(&self) -> () {}
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Enum0 {
     #[inline]
     fn partial_cmp(&self, other: &Enum0)
@@ -642,7 +586,6 @@ impl ::core::cmp::PartialOrd for Enum0 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Enum0 {
     #[inline]
     fn cmp(&self, other: &Enum0) -> ::core::cmp::Ordering {
@@ -657,7 +600,6 @@ enum Enum1 {
     },
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Enum1 {
     #[inline]
     fn clone(&self) -> Enum1 {
@@ -668,7 +610,6 @@ impl ::core::clone::Clone for Enum1 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Enum1 {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         match self {
@@ -679,7 +620,6 @@ impl ::core::fmt::Debug for Enum1 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Enum1 {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         match self {
@@ -690,7 +630,6 @@ impl ::core::hash::Hash for Enum1 {
 }
 impl ::core::marker::StructuralPartialEq for Enum1 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Enum1 {
     #[inline]
     fn eq(&self, other: &Enum1) -> bool {
@@ -709,7 +648,6 @@ impl ::core::cmp::PartialEq for Enum1 {
 }
 impl ::core::marker::StructuralEq for Enum1 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Enum1 {
     #[inline]
     #[doc(hidden)]
@@ -719,7 +657,6 @@ impl ::core::cmp::Eq for Enum1 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Enum1 {
     #[inline]
     fn partial_cmp(&self, other: &Enum1)
@@ -731,7 +668,6 @@ impl ::core::cmp::PartialOrd for Enum1 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Enum1 {
     #[inline]
     fn cmp(&self, other: &Enum1) -> ::core::cmp::Ordering {
@@ -749,39 +685,33 @@ enum Fieldless1 {
     A,
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Fieldless1 {
     #[inline]
     fn clone(&self) -> Fieldless1 { Fieldless1::A }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Fieldless1 {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         ::core::fmt::Formatter::write_str(f, "A")
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Fieldless1 {
     #[inline]
     fn default() -> Fieldless1 { Self::A }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Fieldless1 {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
 }
 impl ::core::marker::StructuralPartialEq for Fieldless1 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Fieldless1 {
     #[inline]
     fn eq(&self, other: &Fieldless1) -> bool { true }
 }
 impl ::core::marker::StructuralEq for Fieldless1 {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Fieldless1 {
     #[inline]
     #[doc(hidden)]
@@ -789,7 +719,6 @@ impl ::core::cmp::Eq for Fieldless1 {
     fn assert_receiver_is_total_eq(&self) -> () {}
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Fieldless1 {
     #[inline]
     fn partial_cmp(&self, other: &Fieldless1)
@@ -798,7 +727,6 @@ impl ::core::cmp::PartialOrd for Fieldless1 {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Fieldless1 {
     #[inline]
     fn cmp(&self, other: &Fieldless1) -> ::core::cmp::Ordering {
@@ -815,16 +743,13 @@ enum Fieldless {
     C,
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Fieldless {
     #[inline]
     fn clone(&self) -> Fieldless { *self }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Fieldless { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Fieldless {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         match self {
@@ -835,13 +760,11 @@ impl ::core::fmt::Debug for Fieldless {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Fieldless {
     #[inline]
     fn default() -> Fieldless { Self::A }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Fieldless {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         let __self_tag = ::core::intrinsics::discriminant_value(self);
@@ -850,7 +773,6 @@ impl ::core::hash::Hash for Fieldless {
 }
 impl ::core::marker::StructuralPartialEq for Fieldless {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Fieldless {
     #[inline]
     fn eq(&self, other: &Fieldless) -> bool {
@@ -861,7 +783,6 @@ impl ::core::cmp::PartialEq for Fieldless {
 }
 impl ::core::marker::StructuralEq for Fieldless {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Fieldless {
     #[inline]
     #[doc(hidden)]
@@ -869,7 +790,6 @@ impl ::core::cmp::Eq for Fieldless {
     fn assert_receiver_is_total_eq(&self) -> () {}
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Fieldless {
     #[inline]
     fn partial_cmp(&self, other: &Fieldless)
@@ -880,7 +800,6 @@ impl ::core::cmp::PartialOrd for Fieldless {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Fieldless {
     #[inline]
     fn cmp(&self, other: &Fieldless) -> ::core::cmp::Ordering {
@@ -903,7 +822,6 @@ enum Mixed {
     },
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Mixed {
     #[inline]
     fn clone(&self) -> Mixed {
@@ -912,10 +830,8 @@ impl ::core::clone::Clone for Mixed {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Mixed { }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Mixed {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         match self {
@@ -931,13 +847,11 @@ impl ::core::fmt::Debug for Mixed {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::default::Default for Mixed {
     #[inline]
     fn default() -> Mixed { Self::P }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Mixed {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         let __self_tag = ::core::intrinsics::discriminant_value(self);
@@ -954,7 +868,6 @@ impl ::core::hash::Hash for Mixed {
 }
 impl ::core::marker::StructuralPartialEq for Mixed {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Mixed {
     #[inline]
     fn eq(&self, other: &Mixed) -> bool {
@@ -987,7 +900,6 @@ impl ::core::cmp::PartialEq for Mixed {
 }
 impl ::core::marker::StructuralEq for Mixed {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Mixed {
     #[inline]
     #[doc(hidden)]
@@ -997,7 +909,6 @@ impl ::core::cmp::Eq for Mixed {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Mixed {
     #[inline]
     fn partial_cmp(&self, other: &Mixed)
@@ -1025,7 +936,6 @@ impl ::core::cmp::PartialOrd for Mixed {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Mixed {
     #[inline]
     fn cmp(&self, other: &Mixed) -> ::core::cmp::Ordering {
@@ -1054,7 +964,6 @@ impl ::core::cmp::Ord for Mixed {
 // for this enum.
 enum Fielded { X(u32), Y(bool), Z(Option<i32>), }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Fielded {
     #[inline]
     fn clone(&self) -> Fielded {
@@ -1069,7 +978,6 @@ impl ::core::clone::Clone for Fielded {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::fmt::Debug for Fielded {
     fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
         match self {
@@ -1086,7 +994,6 @@ impl ::core::fmt::Debug for Fielded {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::hash::Hash for Fielded {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
         let __self_tag = ::core::intrinsics::discriminant_value(self);
@@ -1100,7 +1007,6 @@ impl ::core::hash::Hash for Fielded {
 }
 impl ::core::marker::StructuralPartialEq for Fielded {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialEq for Fielded {
     #[inline]
     fn eq(&self, other: &Fielded) -> bool {
@@ -1135,7 +1041,6 @@ impl ::core::cmp::PartialEq for Fielded {
 }
 impl ::core::marker::StructuralEq for Fielded {}
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Eq for Fielded {
     #[inline]
     #[doc(hidden)]
@@ -1147,7 +1052,6 @@ impl ::core::cmp::Eq for Fielded {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::PartialOrd for Fielded {
     #[inline]
     fn partial_cmp(&self, other: &Fielded)
@@ -1170,7 +1074,6 @@ impl ::core::cmp::PartialOrd for Fielded {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::cmp::Ord for Fielded {
     #[inline]
     fn cmp(&self, other: &Fielded) -> ::core::cmp::Ordering {
@@ -1199,7 +1102,6 @@ pub union Union {
     pub i: i32,
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::clone::Clone for Union {
     #[inline]
     fn clone(&self) -> Union {
@@ -1208,5 +1110,4 @@ impl ::core::clone::Clone for Union {
     }
 }
 #[automatically_derived]
-#[allow(unused_qualifications)]
 impl ::core::marker::Copy for Union { }
diff --git a/src/test/ui/impl-trait/issue-99073-2.rs b/src/test/ui/impl-trait/issue-99073-2.rs
new file mode 100644
index 00000000000..bebd8286de9
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-99073-2.rs
@@ -0,0 +1,17 @@
+use std::fmt::Display;
+
+fn main() {
+    test("hi", true);
+}
+
+fn test<T: Display>(t: T, recurse: bool) -> impl Display {
+    let f = || {
+        let i: u32 = test::<i32>(-1, false);
+        //~^ ERROR mismatched types
+        println!("{i}");
+    };
+    if recurse {
+        f();
+    }
+    t
+}
diff --git a/src/test/ui/impl-trait/issue-99073-2.stderr b/src/test/ui/impl-trait/issue-99073-2.stderr
new file mode 100644
index 00000000000..c1e4b823c08
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-99073-2.stderr
@@ -0,0 +1,15 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-99073-2.rs:9:22
+   |
+LL | fn test<T: Display>(t: T, recurse: bool) -> impl Display {
+   |                                             ------------ the expected opaque type
+LL |     let f = || {
+LL |         let i: u32 = test::<i32>(-1, false);
+   |                      ^^^^^^^^^^^^^^^^^^^^^^ types differ
+   |
+   = note: expected opaque type `impl std::fmt::Display`
+                     found type `u32`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/impl-trait/issue-99073.rs b/src/test/ui/impl-trait/issue-99073.rs
new file mode 100644
index 00000000000..1d75f608666
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-99073.rs
@@ -0,0 +1,8 @@
+fn main() {
+    let _ = fix(|_: &dyn Fn()| {});
+}
+
+fn fix<F: Fn(G), G: Fn()>(f: F) -> impl Fn() {
+    move || f(fix(&f))
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/impl-trait/issue-99073.stderr b/src/test/ui/impl-trait/issue-99073.stderr
new file mode 100644
index 00000000000..b35d58093d5
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-99073.stderr
@@ -0,0 +1,14 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-99073.rs:6:13
+   |
+LL | fn fix<F: Fn(G), G: Fn()>(f: F) -> impl Fn() {
+   |                                    --------- the expected opaque type
+LL |     move || f(fix(&f))
+   |             ^^^^^^^^^^ types differ
+   |
+   = note: expected opaque type `impl Fn()`
+           found type parameter `G`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.rs b/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.rs
index d29a82f76a7..b05579f2166 100644
--- a/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.rs
+++ b/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.rs
@@ -6,7 +6,7 @@ type Tait = impl Sized;
 
 impl Foo for Concrete {
     type Item = Concrete;
-    //~^ mismatched types
+    //~^ type mismatch resolving
 }
 
 impl Bar for Concrete {
diff --git a/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.stderr b/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.stderr
index a25f0cd8761..f0dceb1b11a 100644
--- a/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.stderr
+++ b/src/test/ui/impl-trait/issues/issue-99348-impl-compatibility.stderr
@@ -1,15 +1,25 @@
-error[E0308]: mismatched types
+error[E0271]: type mismatch resolving `<Concrete as Bar>::Other == Concrete`
   --> $DIR/issue-99348-impl-compatibility.rs:8:17
    |
 LL | type Tait = impl Sized;
-   |             ---------- the expected opaque type
+   |             ---------- the found opaque type
 ...
 LL |     type Item = Concrete;
-   |                 ^^^^^^^^ types differ
+   |                 ^^^^^^^^ type mismatch resolving `<Concrete as Bar>::Other == Concrete`
    |
-   = note: expected opaque type `Tait`
-                   found struct `Concrete`
+note: expected this to be `Concrete`
+  --> $DIR/issue-99348-impl-compatibility.rs:13:18
+   |
+LL |     type Other = Tait;
+   |                  ^^^^
+   = note:   expected struct `Concrete`
+           found opaque type `Tait`
+note: required by a bound in `Foo::Item`
+  --> $DIR/issue-99348-impl-compatibility.rs:17:20
+   |
+LL |     type Item: Bar<Other = Self>;
+   |                    ^^^^^^^^^^^^ required by this bound in `Foo::Item`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0308`.
+For more information about this error, try `rustc --explain E0271`.
diff --git a/src/test/ui/lint/auxiliary/add-impl.rs b/src/test/ui/lint/auxiliary/add-impl.rs
new file mode 100644
index 00000000000..9d0e3068aed
--- /dev/null
+++ b/src/test/ui/lint/auxiliary/add-impl.rs
@@ -0,0 +1,22 @@
+// force-host
+// no-prefer-dynamic
+
+#![crate_type = "proc-macro"]
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro_derive(AddImpl)]
+// Unnecessary qualification `bar::foo`
+// https://github.com/rust-lang/rust/issues/71898
+pub fn derive(input: TokenStream) -> TokenStream {
+    "impl B {
+            fn foo(&self) { use bar::foo; bar::foo() }
+        }
+
+        fn foo() {}
+
+        mod bar { pub fn foo() {} }
+    ".parse().unwrap()
+}
diff --git a/src/test/ui/lint/unused-qualification-in-derive-expansion.rs b/src/test/ui/lint/unused-qualification-in-derive-expansion.rs
new file mode 100644
index 00000000000..c2efbf507fe
--- /dev/null
+++ b/src/test/ui/lint/unused-qualification-in-derive-expansion.rs
@@ -0,0 +1,16 @@
+// run-pass
+// aux-build:add-impl.rs
+
+#![forbid(unused_qualifications)]
+
+#[macro_use]
+extern crate add_impl;
+
+#[derive(AddImpl)]
+struct B;
+
+fn main() {
+    B.foo();
+    foo();
+    bar::foo();
+}
diff --git a/src/test/ui/parser/fn-header-semantic-fail.rs b/src/test/ui/parser/fn-header-semantic-fail.rs
index c2954868f78..8ff14fb1f30 100644
--- a/src/test/ui/parser/fn-header-semantic-fail.rs
+++ b/src/test/ui/parser/fn-header-semantic-fail.rs
@@ -27,7 +27,7 @@ fn main() {
     struct Y;
     impl X for Y {
         async fn ft1() {} //~ ERROR functions in traits cannot be declared `async`
-        //~^ ERROR impl has stricter requirements than trait
+        //~^ ERROR has an incompatible type for trait
         unsafe fn ft2() {} // OK.
         const fn ft3() {} //~ ERROR functions in traits cannot be declared const
         extern "C" fn ft4() {}
@@ -36,7 +36,7 @@ fn main() {
         //~| ERROR functions in traits cannot be declared const
         //~| ERROR functions cannot be both `const` and `async`
         //~| ERROR cycle detected
-        //~| ERROR impl has stricter requirements than trait
+        //~| ERROR has an incompatible type for trait
     }
 
     impl Y {
diff --git a/src/test/ui/parser/fn-header-semantic-fail.stderr b/src/test/ui/parser/fn-header-semantic-fail.stderr
index 75d27c614e2..bc51ba8b8c5 100644
--- a/src/test/ui/parser/fn-header-semantic-fail.stderr
+++ b/src/test/ui/parser/fn-header-semantic-fail.stderr
@@ -216,23 +216,41 @@ LL | |     }
 LL | | }
    | |_^
 
-error[E0276]: impl has stricter requirements than trait
-  --> $DIR/fn-header-semantic-fail.rs:29:9
+error[E0053]: method `ft1` has an incompatible type for trait
+  --> $DIR/fn-header-semantic-fail.rs:29:24
    |
-LL |         async fn ft1();
-   |         --------------- definition of `ft1` from trait
-...
 LL |         async fn ft1() {}
-   |         ^^^^^^^^^^^^^^ impl has extra requirement `(): Future`
+   |                        ^
+   |                        |
+   |                        checked the `Output` of this `async fn`, found opaque type
+   |                        expected `()`, found opaque type
+   |
+   = note: while checking the return type of the `async fn`
+note: type in trait
+  --> $DIR/fn-header-semantic-fail.rs:17:23
+   |
+LL |         async fn ft1();
+   |                       ^
+   = note: expected fn pointer `fn()`
+              found fn pointer `fn() -> impl Future<Output = ()>`
 
-error[E0276]: impl has stricter requirements than trait
-  --> $DIR/fn-header-semantic-fail.rs:34:9
+error[E0053]: method `ft5` has an incompatible type for trait
+  --> $DIR/fn-header-semantic-fail.rs:34:48
    |
-LL |         const async unsafe extern "C" fn ft5();
-   |         --------------------------------------- definition of `ft5` from trait
-...
 LL |         const async unsafe extern "C" fn ft5() {}
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ impl has extra requirement `(): Future`
+   |                                                ^
+   |                                                |
+   |                                                checked the `Output` of this `async fn`, found opaque type
+   |                                                expected `()`, found opaque type
+   |
+   = note: while checking the return type of the `async fn`
+note: type in trait
+  --> $DIR/fn-header-semantic-fail.rs:21:47
+   |
+LL |         const async unsafe extern "C" fn ft5();
+   |                                               ^
+   = note: expected fn pointer `unsafe extern "C" fn()`
+              found fn pointer `unsafe extern "C" fn() -> impl Future<Output = ()>`
 
 error[E0391]: cycle detected when computing type of `main::<impl at $DIR/fn-header-semantic-fail.rs:28:5: 28:17>::ft5::{opaque#0}`
   --> $DIR/fn-header-semantic-fail.rs:34:48
@@ -308,5 +326,5 @@ LL | | }
 
 error: aborting due to 23 previous errors
 
-Some errors have detailed explanations: E0276, E0379, E0391, E0706.
-For more information about an error, try `rustc --explain E0276`.
+Some errors have detailed explanations: E0053, E0379, E0391, E0706.
+For more information about an error, try `rustc --explain E0053`.
diff --git a/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.rs b/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.rs
index 6facc467f7a..aaf0f7eaef0 100644
--- a/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.rs
+++ b/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.rs
@@ -14,7 +14,7 @@ trait B {
 impl B for A {
     async fn associated(); //~ ERROR without body
     //~^ ERROR cannot be declared `async`
-    //~| ERROR impl has stricter requirements than trait
+    //~| ERROR has an incompatible type for trait
 }
 
 fn main() {}
diff --git a/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.stderr b/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.stderr
index c144060a859..d3214458eac 100644
--- a/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.stderr
+++ b/src/test/ui/resolve/issue-70736-async-fn-no-body-def-collector.stderr
@@ -44,16 +44,25 @@ LL |     async fn associated();
    = note: `async` trait functions are not currently supported
    = note: consider using the `async-trait` crate: https://crates.io/crates/async-trait
 
-error[E0276]: impl has stricter requirements than trait
-  --> $DIR/issue-70736-async-fn-no-body-def-collector.rs:15:5
+error[E0053]: method `associated` has an incompatible type for trait
+  --> $DIR/issue-70736-async-fn-no-body-def-collector.rs:15:26
    |
 LL |     async fn associated();
-   |     ---------------------- definition of `associated` from trait
-...
+   |                          ^
+   |                          |
+   |                          checked the `Output` of this `async fn`, found opaque type
+   |                          expected `()`, found opaque type
+   |
+   = note: while checking the return type of the `async fn`
+note: type in trait
+  --> $DIR/issue-70736-async-fn-no-body-def-collector.rs:11:26
+   |
 LL |     async fn associated();
-   |     ^^^^^^^^^^^^^^^^^^^^^^ impl has extra requirement `(): Future`
+   |                          ^
+   = note: expected fn pointer `fn()`
+              found fn pointer `fn() -> impl Future<Output = ()>`
 
 error: aborting due to 6 previous errors
 
-Some errors have detailed explanations: E0276, E0706.
-For more information about an error, try `rustc --explain E0276`.
+Some errors have detailed explanations: E0053, E0706.
+For more information about an error, try `rustc --explain E0053`.
diff --git a/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.rs b/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.rs
index 377ce85e8b2..4a11bb5020e 100644
--- a/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.rs
+++ b/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.rs
@@ -3,7 +3,7 @@
 type Foo = impl Fn() -> Foo;
 
 fn foo() -> Foo {
-//~^ ERROR: overflow evaluating the requirement `fn() -> Foo {foo}: Sized`
+//~^ ERROR: overflow evaluating the requirement
     foo
 }
 
diff --git a/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.stderr b/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.stderr
index d20b1cc6d85..00c682b2193 100644
--- a/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.stderr
+++ b/src/test/ui/type-alias-impl-trait/issue-53398-cyclic-types.stderr
@@ -1,10 +1,8 @@
-error[E0275]: overflow evaluating the requirement `fn() -> Foo {foo}: Sized`
+error[E0275]: overflow evaluating the requirement `<fn() -> Foo {foo} as FnOnce<()>>::Output == fn() -> Foo {foo}`
   --> $DIR/issue-53398-cyclic-types.rs:5:13
    |
 LL | fn foo() -> Foo {
    |             ^^^
-   |
-   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_53398_cyclic_types`)
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/type-alias-impl-trait/issue-57961.rs b/src/test/ui/type-alias-impl-trait/issue-57961.rs
new file mode 100644
index 00000000000..472886c9caa
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/issue-57961.rs
@@ -0,0 +1,18 @@
+#![feature(type_alias_impl_trait)]
+
+type X = impl Sized;
+
+trait Foo {
+    type Bar: Iterator<Item = X>;
+}
+
+impl Foo for () {
+    type Bar = std::vec::IntoIter<u32>;
+    //~^ ERROR type mismatch resolving `<std::vec::IntoIter<u32> as Iterator>::Item == X
+}
+
+fn incoherent() {
+    let f: X = 22_i32;
+}
+
+fn main() {}
diff --git a/src/test/ui/type-alias-impl-trait/issue-57961.stderr b/src/test/ui/type-alias-impl-trait/issue-57961.stderr
new file mode 100644
index 00000000000..ed4caf6ce68
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/issue-57961.stderr
@@ -0,0 +1,20 @@
+error[E0271]: type mismatch resolving `<std::vec::IntoIter<u32> as Iterator>::Item == X`
+  --> $DIR/issue-57961.rs:10:16
+   |
+LL | type X = impl Sized;
+   |          ---------- the expected opaque type
+...
+LL |     type Bar = std::vec::IntoIter<u32>;
+   |                ^^^^^^^^^^^^^^^^^^^^^^^ expected opaque type, found `u32`
+   |
+   = note: expected opaque type `X`
+                     found type `u32`
+note: required by a bound in `Foo::Bar`
+  --> $DIR/issue-57961.rs:6:24
+   |
+LL |     type Bar: Iterator<Item = X>;
+   |                        ^^^^^^^^ required by this bound in `Foo::Bar`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0271`.