diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
index 7ea21b24fc821..8bcdd44ccbedd 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
@@ -138,6 +138,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
     let name_str = intrinsic_name.as_str();
 
     let bound_vars = tcx.mk_bound_variable_kinds(&[
+        ty::BoundVariableKind::Region(ty::BrAnon),
         ty::BoundVariableKind::Region(ty::BrAnon),
         ty::BoundVariableKind::Region(ty::BrEnv),
     ]);
@@ -151,7 +152,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
             let env_region = ty::Region::new_bound(
                 tcx,
                 ty::INNERMOST,
-                ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
+                ty::BoundRegion { var: ty::BoundVar::from_u32(2), kind: ty::BrEnv },
             );
             let va_list_ty = tcx.type_of(did).instantiate(tcx, &[region.into()]);
             (Ty::new_ref(tcx, env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
@@ -446,9 +447,12 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
 
             sym::raw_eq => {
                 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon };
-                let param_ty =
+                let param_ty_lhs =
+                    Ty::new_imm_ref(tcx, ty::Region::new_bound(tcx, ty::INNERMOST, br), param(0));
+                let br = ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrAnon };
+                let param_ty_rhs =
                     Ty::new_imm_ref(tcx, ty::Region::new_bound(tcx, ty::INNERMOST, br), param(0));
-                (1, vec![param_ty; 2], tcx.types.bool)
+                (1, vec![param_ty_lhs, param_ty_rhs], tcx.types.bool)
             }
 
             sym::black_box => (1, vec![param(0)], param(0)),
diff --git a/compiler/rustc_infer/src/infer/equate.rs b/compiler/rustc_infer/src/infer/equate.rs
index 5d929394eb04c..b33cdd1e35e3b 100644
--- a/compiler/rustc_infer/src/infer/equate.rs
+++ b/compiler/rustc_infer/src/infer/equate.rs
@@ -4,10 +4,11 @@ use crate::traits::PredicateObligations;
 use super::combine::{CombineFields, ObligationEmittingRelation};
 use super::Subtype;
 
+use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
 use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::TyVar;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, Ty, TyCtxt};
 
 use rustc_hir::def_id::DefId;
 
@@ -164,14 +165,18 @@ impl<'tcx> TypeRelation<'tcx> for Equate<'_, '_, 'tcx> {
             return Ok(a);
         }
 
-        if a.skip_binder().has_escaping_bound_vars() || b.skip_binder().has_escaping_bound_vars() {
-            self.fields.higher_ranked_sub(a, b, self.a_is_expected)?;
-            self.fields.higher_ranked_sub(b, a, self.a_is_expected)?;
+        let a = self.tcx().anonymize_bound_vars(a);
+        let b = self.tcx().anonymize_bound_vars(b);
+
+        if a.bound_vars() == b.bound_vars() {
+            let (a, b) = self
+                .fields
+                .infcx
+                .instantiate_binder_with_placeholders(a.map_bound(|a| (a, b.skip_binder())));
+            Ok(ty::Binder::dummy(self.relate(a, b)?))
         } else {
-            // Fast path for the common case.
-            self.relate(a.skip_binder(), b.skip_binder())?;
+            Err(TypeError::Mismatch)
         }
-        Ok(a)
     }
 }
 
diff --git a/tests/ui/associated-inherent-types/issue-109789.rs b/tests/ui/associated-inherent-types/issue-109789.rs
index 0b5ba7d1fb55d..b1402c26e1f60 100644
--- a/tests/ui/associated-inherent-types/issue-109789.rs
+++ b/tests/ui/associated-inherent-types/issue-109789.rs
@@ -16,7 +16,6 @@ impl Other for u32 {}
 // `try_report_trait_placeholder_mismatch`.
 
 fn bar(_: Foo<for<'a> fn(&'a ())>::Assoc) {}
-//~^ ERROR mismatched types
-//~| ERROR mismatched types
+//~^ ERROR associated type `Assoc` not found for `Foo<for<'a> fn(&'a ())>` in the current scope [E0220]
 
 fn main() {}
diff --git a/tests/ui/associated-inherent-types/issue-109789.stderr b/tests/ui/associated-inherent-types/issue-109789.stderr
index e844f6795e6f8..415d774b85fa1 100644
--- a/tests/ui/associated-inherent-types/issue-109789.stderr
+++ b/tests/ui/associated-inherent-types/issue-109789.stderr
@@ -1,22 +1,15 @@
-error[E0308]: mismatched types
-  --> $DIR/issue-109789.rs:18:11
+error[E0220]: associated type `Assoc` not found for `Foo<for<'a> fn(&'a ())>` in the current scope
+  --> $DIR/issue-109789.rs:18:36
    |
+LL | struct Foo<T>(T);
+   | ------------- associated item `Assoc` not found for this struct
+...
 LL | fn bar(_: Foo<for<'a> fn(&'a ())>::Assoc) {}
-   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
+   |                                    ^^^^^ associated item not found in `Foo<for<'a> fn(&'a ())>`
    |
-   = note: expected struct `Foo<fn(&'static ())>`
-              found struct `Foo<for<'a> fn(&'a ())>`
+   = note: the associated type was found for
+           - `Foo<fn(&'static ())>`
 
-error[E0308]: mismatched types
-  --> $DIR/issue-109789.rs:18:11
-   |
-LL | fn bar(_: Foo<for<'a> fn(&'a ())>::Assoc) {}
-   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
-   |
-   = note: expected struct `Foo<fn(&'static ())>`
-              found struct `Foo<for<'a> fn(&'a ())>`
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+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 E0220`.
diff --git a/tests/ui/associated-inherent-types/issue-111404-1.stderr b/tests/ui/associated-inherent-types/issue-111404-1.stderr
index c55f1432389c7..b39b716977977 100644
--- a/tests/ui/associated-inherent-types/issue-111404-1.stderr
+++ b/tests/ui/associated-inherent-types/issue-111404-1.stderr
@@ -1,8 +1,33 @@
+error[E0220]: associated type `Assoc` not found for `Foo<for<'b> fn(&'b ())>` in the current scope
+  --> $DIR/issue-111404-1.rs:10:55
+   |
+LL | struct Foo<T>(T);
+   | ------------- associated item `Assoc` not found for this struct
+...
+LL | fn bar(_: fn(Foo<for<'b> fn(Foo<fn(&'b ())>::Assoc)>::Assoc)) {}
+<<<<<<< HEAD
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+||||||| parent of 9bb25a65025 (Make type equality != bidirectional subtyping)
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
 error: higher-ranked subtype error
   --> $DIR/issue-111404-1.rs:10:1
    |
 LL | fn bar(_: fn(Foo<for<'b> fn(Foo<fn(&'b ())>::Assoc)>::Assoc)) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: aborting due to 2 previous errors
+=======
+   |                                                       ^^^^^ associated item not found in `Foo<for<'b> fn(&'b ())>`
+   |
+   = note: the associated type was found for
+           - `Foo<fn(&'a ())>`
 
 error: aborting due to previous error
+>>>>>>> 9bb25a65025 (Make type equality != bidirectional subtyping)
 
+For more information about this error, try `rustc --explain E0220`.
diff --git a/tests/ui/closure-expected-type/expect-fn-supply-fn.rs b/tests/ui/closure-expected-type/expect-fn-supply-fn.rs
index 7f1c140279c4e..6f7f69eed6a47 100644
--- a/tests/ui/closure-expected-type/expect-fn-supply-fn.rs
+++ b/tests/ui/closure-expected-type/expect-fn-supply-fn.rs
@@ -14,8 +14,6 @@ fn expect_free_supply_free_from_fn<'x>(x: &'x u32) {
     // Here, the type given for `'x` "obscures" a region from the
     // expected signature that is bound at closure level.
     with_closure_expecting_fn_with_free_region(|x: fn(&'x u32), y| {});
-    //~^ ERROR lifetime may not live long enough
-    //~| ERROR lifetime may not live long enough
 }
 
 fn expect_free_supply_free_from_closure() {
@@ -30,14 +28,14 @@ fn expect_free_supply_bound() {
     // Here, we are given a function whose region is bound at closure level,
     // but we expect one bound in the argument. Error results.
     with_closure_expecting_fn_with_free_region(|x: fn(&u32), y| {});
-    //~^ ERROR mismatched types
+    //~^ ERROR type mismatch in closure arguments
 }
 
 fn expect_bound_supply_free_from_fn<'x>(x: &'x u32) {
     // Here, we are given a `fn(&u32)` but we expect a `fn(&'x
     // u32)`. In principle, this could be ok, but we demand equality.
     with_closure_expecting_fn_with_bound_region(|x: fn(&'x u32), y| {});
-    //~^ ERROR mismatched types
+    //~^ ERROR type mismatch in closure arguments
 }
 
 fn expect_bound_supply_free_from_closure() {
@@ -46,7 +44,7 @@ fn expect_bound_supply_free_from_closure() {
     // the argument level.
     type Foo<'a> = fn(&'a u32);
     with_closure_expecting_fn_with_bound_region(|x: Foo<'_>, y| {
-        //~^ ERROR mismatched types
+        //~^ ERROR type mismatch in closure arguments
     });
 }
 
diff --git a/tests/ui/closure-expected-type/expect-fn-supply-fn.stderr b/tests/ui/closure-expected-type/expect-fn-supply-fn.stderr
index e6ddc60689779..5563ae242d65b 100644
--- a/tests/ui/closure-expected-type/expect-fn-supply-fn.stderr
+++ b/tests/ui/closure-expected-type/expect-fn-supply-fn.stderr
@@ -1,51 +1,72 @@
-error: lifetime may not live long enough
-  --> $DIR/expect-fn-supply-fn.rs:16:49
-   |
-LL | fn expect_free_supply_free_from_fn<'x>(x: &'x u32) {
-   |                                    -- lifetime `'x` defined here
-...
-LL |     with_closure_expecting_fn_with_free_region(|x: fn(&'x u32), y| {});
-   |                                                 ^
-   |                                                 |
-   |                                                 has type `fn(&'1 u32)`
-   |                                                 requires that `'1` must outlive `'x`
-
-error: lifetime may not live long enough
-  --> $DIR/expect-fn-supply-fn.rs:16:49
-   |
-LL | fn expect_free_supply_free_from_fn<'x>(x: &'x u32) {
-   |                                    -- lifetime `'x` defined here
-...
-LL |     with_closure_expecting_fn_with_free_region(|x: fn(&'x u32), y| {});
-   |                                                 ^ requires that `'x` must outlive `'static`
-
-error[E0308]: mismatched types
-  --> $DIR/expect-fn-supply-fn.rs:32:49
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/expect-fn-supply-fn.rs:30:5
    |
 LL |     with_closure_expecting_fn_with_free_region(|x: fn(&u32), y| {});
-   |                                                 ^ one type is more general than the other
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ---------------- found signature defined here
+   |     |
+   |     expected due to this
+   |
+   = note: expected closure signature `for<'a, 'b> fn(for<'a> fn(&'a u32), &'b i32) -> _`
+              found closure signature `fn(for<'a> fn(&'a u32), _) -> _`
+note: required by a bound in `with_closure_expecting_fn_with_free_region`
+  --> $DIR/expect-fn-supply-fn.rs:3:8
+   |
+LL | fn with_closure_expecting_fn_with_free_region<F>(_: F)
+   |    ------------------------------------------ required by a bound in this function
+LL | where
+LL |     F: for<'a> FnOnce(fn(&'a u32), &i32),
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `with_closure_expecting_fn_with_free_region`
+help: consider adjusting the signature so it borrows its argument
    |
-   = note: expected fn pointer `fn(&u32)`
-              found fn pointer `for<'a> fn(&'a u32)`
+LL |     with_closure_expecting_fn_with_free_region(|x: fn(&u32), &y| {});
+   |                                                              +
 
-error[E0308]: mismatched types
-  --> $DIR/expect-fn-supply-fn.rs:39:50
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/expect-fn-supply-fn.rs:37:5
    |
 LL |     with_closure_expecting_fn_with_bound_region(|x: fn(&'x u32), y| {});
-   |                                                  ^ one type is more general than the other
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------- found signature defined here
+   |     |
+   |     expected due to this
    |
-   = note: expected fn pointer `for<'a> fn(&'a u32)`
-              found fn pointer `fn(&u32)`
+   = note: expected closure signature `for<'a> fn(for<'a> fn(&'a u32), &'a i32) -> _`
+              found closure signature `fn(fn(&'x u32), _) -> _`
+note: required by a bound in `with_closure_expecting_fn_with_bound_region`
+  --> $DIR/expect-fn-supply-fn.rs:9:8
+   |
+LL | fn with_closure_expecting_fn_with_bound_region<F>(_: F)
+   |    ------------------------------------------- required by a bound in this function
+LL | where
+LL |     F: FnOnce(fn(&u32), &i32),
+   |        ^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `with_closure_expecting_fn_with_bound_region`
+help: consider adjusting the signature so it borrows its argument
+   |
+LL |     with_closure_expecting_fn_with_bound_region(|x: fn(&'x u32), &y| {});
+   |                                                                  +
 
-error[E0308]: mismatched types
-  --> $DIR/expect-fn-supply-fn.rs:48:50
+error[E0631]: type mismatch in closure arguments
+  --> $DIR/expect-fn-supply-fn.rs:46:5
    |
 LL |     with_closure_expecting_fn_with_bound_region(|x: Foo<'_>, y| {
-   |                                                  ^ one type is more general than the other
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ --------------- found signature defined here
+   |     |
+   |     expected due to this
+   |
+   = note: expected closure signature `for<'a> fn(for<'a> fn(&'a u32), &'a i32) -> _`
+              found closure signature `for<'a> fn(for<'a> fn(&'a u32), _) -> _`
+note: required by a bound in `with_closure_expecting_fn_with_bound_region`
+  --> $DIR/expect-fn-supply-fn.rs:9:8
+   |
+LL | fn with_closure_expecting_fn_with_bound_region<F>(_: F)
+   |    ------------------------------------------- required by a bound in this function
+LL | where
+LL |     F: FnOnce(fn(&u32), &i32),
+   |        ^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `with_closure_expecting_fn_with_bound_region`
+help: consider adjusting the signature so it borrows its argument
    |
-   = note: expected fn pointer `for<'a> fn(&'a u32)`
-              found fn pointer `fn(&u32)`
+LL |     with_closure_expecting_fn_with_bound_region(|x: Foo<'_>, &y| {
+   |                                                              +
 
-error: aborting due to 5 previous errors
+error: aborting due to 3 previous errors
 
-For more information about this error, try `rustc --explain E0308`.
+For more information about this error, try `rustc --explain E0631`.
diff --git a/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.rs b/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.rs
index 99f805f7f0f63..6eab905d9eee3 100644
--- a/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.rs
+++ b/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.rs
@@ -10,12 +10,14 @@
 //   * true if `exists<'r> { 'r: 'static }` (obviously true)
 // * `fn(fn(&'static u32)) <: for<'r> fn(fn(&'r u32))`
 //   * true if `forall<'r> { 'static: 'r }` (also true)
+//
+// check-pass
+
 
 trait Trait {}
 
 impl Trait for for<'r> fn(fn(&'r ())) {}
 impl<'a> Trait for fn(fn(&'a ())) {}
-//~^ ERROR conflicting implementations
 //
 // Note in particular that we do NOT get a future-compatibility warning
 // here. This is because the new leak-check proposed in [MCP 295] does not
diff --git a/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr b/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr
deleted file mode 100644
index 7dabd97b94e82..0000000000000
--- a/tests/ui/coherence/coherence-fn-covariant-bound-vs-static.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error[E0119]: conflicting implementations of trait `Trait` for type `for<'r> fn(fn(&'r ()))`
-  --> $DIR/coherence-fn-covariant-bound-vs-static.rs:17:1
-   |
-LL | impl Trait for for<'r> fn(fn(&'r ())) {}
-   | ------------------------------------- first implementation here
-LL | impl<'a> Trait for fn(fn(&'a ())) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'r> fn(fn(&'r ()))`
-   |
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-fn-implied-bounds.rs b/tests/ui/coherence/coherence-fn-implied-bounds.rs
index 4539af9a32e38..5252132a4ad22 100644
--- a/tests/ui/coherence/coherence-fn-implied-bounds.rs
+++ b/tests/ui/coherence/coherence-fn-implied-bounds.rs
@@ -11,16 +11,12 @@
 // Note that while we would like to make this a hard error, we also
 // give the same warning for `coherence-wasm-bindgen.rs`, which ought
 // to be accepted.
-
-#![deny(coherence_leak_check)]
-
+//
+// check-pass
 trait Trait {}
 
 impl Trait for for<'a, 'b> fn(&'a &'b u32, &'b &'a u32) -> &'b u32 {}
 
-impl Trait for for<'c> fn(&'c &'c u32, &'c &'c u32) -> &'c u32 {
-    //~^ ERROR conflicting implementations
-    //~| WARNING this was previously accepted by the compiler
-}
+impl Trait for for<'c> fn(&'c &'c u32, &'c &'c u32) -> &'c u32 {}
 
 fn main() {}
diff --git a/tests/ui/coherence/coherence-fn-implied-bounds.stderr b/tests/ui/coherence/coherence-fn-implied-bounds.stderr
deleted file mode 100644
index 2018712043e23..0000000000000
--- a/tests/ui/coherence/coherence-fn-implied-bounds.stderr
+++ /dev/null
@@ -1,20 +0,0 @@
-error: conflicting implementations of trait `Trait` for type `for<'a, 'b> fn(&'a &'b u32, &'b &'a u32) -> &'b u32`
-  --> $DIR/coherence-fn-implied-bounds.rs:21:1
-   |
-LL | impl Trait for for<'a, 'b> fn(&'a &'b u32, &'b &'a u32) -> &'b u32 {}
-   | ------------------------------------------------------------------ first implementation here
-LL |
-LL | impl Trait for for<'c> fn(&'c &'c u32, &'c &'c u32) -> &'c u32 {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'a, 'b> fn(&'a &'b u32, &'b &'a u32) -> &'b u32`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-note: the lint level is defined here
-  --> $DIR/coherence-fn-implied-bounds.rs:15:9
-   |
-LL | #![deny(coherence_leak_check)]
-   |         ^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/coherence/coherence-fn-inputs.rs b/tests/ui/coherence/coherence-fn-inputs.rs
index 3afec5c5459af..5fcdb585c8156 100644
--- a/tests/ui/coherence/coherence-fn-inputs.rs
+++ b/tests/ui/coherence/coherence-fn-inputs.rs
@@ -9,17 +9,11 @@
 //
 // * `'c` can be the intersection of `'a` and `'b` (and there is always an intersection)
 // * `'a` and `'b` can both be equal to `'c`
+//
+// check-pass
 
 trait Trait {}
 impl Trait for for<'a, 'b> fn(&'a u32, &'b u32) {}
-impl Trait for for<'c> fn(&'c u32, &'c u32) {
-    //~^ ERROR conflicting implementations
-    //
-    // Note in particular that we do NOT get a future-compatibility warning
-    // here. This is because the new leak-check proposed in [MCP 295] does not
-    // "error" when these two types are equated.
-    //
-    // [MCP 295]: https://github.com/rust-lang/compiler-team/issues/295
-}
+impl Trait for for<'c> fn(&'c u32, &'c u32) {}
 
 fn main() {}
diff --git a/tests/ui/coherence/coherence-fn-inputs.stderr b/tests/ui/coherence/coherence-fn-inputs.stderr
deleted file mode 100644
index 82bd8a35f4575..0000000000000
--- a/tests/ui/coherence/coherence-fn-inputs.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error[E0119]: conflicting implementations of trait `Trait` for type `for<'a, 'b> fn(&'a u32, &'b u32)`
-  --> $DIR/coherence-fn-inputs.rs:15:1
-   |
-LL | impl Trait for for<'a, 'b> fn(&'a u32, &'b u32) {}
-   | ----------------------------------------------- first implementation here
-LL | impl Trait for for<'c> fn(&'c u32, &'c u32) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'a, 'b> fn(&'a u32, &'b u32)`
-   |
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-free-vs-bound-region.rs b/tests/ui/coherence/coherence-free-vs-bound-region.rs
index 2f5c49d293d5d..ac01e09a1508d 100644
--- a/tests/ui/coherence/coherence-free-vs-bound-region.rs
+++ b/tests/ui/coherence/coherence-free-vs-bound-region.rs
@@ -1,11 +1,12 @@
 // Capture a coherence pattern from wasm-bindgen that we discovered as part of
-// future-compatibility warning #56105. This pattern currently receives a lint
-// warning but we probably want to support it long term.
+// future-compatibility warning #56105.
 //
 // Key distinction: we are implementing once for `A` (take ownership) and one
 // for `&A` (borrow).
 //
 // c.f. #56105
+//
+// check-pass
 
 #![deny(coherence_leak_check)]
 
@@ -13,9 +14,6 @@ trait TheTrait {}
 
 impl<'a> TheTrait for fn(&'a u8) {}
 
-impl TheTrait for fn(&u8) {
-    //~^ ERROR conflicting implementations of trait
-    //~| WARNING this was previously accepted by the compiler
-}
+impl TheTrait for fn(&u8) {}
 
 fn main() {}
diff --git a/tests/ui/coherence/coherence-free-vs-bound-region.stderr b/tests/ui/coherence/coherence-free-vs-bound-region.stderr
deleted file mode 100644
index e2d84b833200c..0000000000000
--- a/tests/ui/coherence/coherence-free-vs-bound-region.stderr
+++ /dev/null
@@ -1,20 +0,0 @@
-error: conflicting implementations of trait `TheTrait` for type `fn(&u8)`
-  --> $DIR/coherence-free-vs-bound-region.rs:16:1
-   |
-LL | impl<'a> TheTrait for fn(&'a u8) {}
-   | -------------------------------- first implementation here
-LL |
-LL | impl TheTrait for fn(&u8) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `fn(&u8)`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-note: the lint level is defined here
-  --> $DIR/coherence-free-vs-bound-region.rs:10:9
-   |
-LL | #![deny(coherence_leak_check)]
-   |         ^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/coherence/coherence-inherited-subtyping.rs b/tests/ui/coherence/coherence-inherited-subtyping.rs
index f35cd2103da4a..69f5ea584ebbe 100644
--- a/tests/ui/coherence/coherence-inherited-subtyping.rs
+++ b/tests/ui/coherence/coherence-inherited-subtyping.rs
@@ -3,13 +3,14 @@
 //
 // Note: This scenario is currently accepted, but as part of the
 // universe transition (#56105) may eventually become an error.
-
+//
+// check-pass
 struct Foo<T> {
     t: T,
 }
 
 impl Foo<for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8> {
-    fn method1(&self) {} //~ ERROR duplicate definitions with name `method1`
+    fn method1(&self) {}
 }
 
 impl Foo<for<'a> fn(&'a u8, &'a u8) -> &'a u8> {
diff --git a/tests/ui/coherence/coherence-inherited-subtyping.stderr b/tests/ui/coherence/coherence-inherited-subtyping.stderr
deleted file mode 100644
index f60b2aa2735d5..0000000000000
--- a/tests/ui/coherence/coherence-inherited-subtyping.stderr
+++ /dev/null
@@ -1,14 +0,0 @@
-error[E0592]: duplicate definitions with name `method1`
-  --> $DIR/coherence-inherited-subtyping.rs:12:5
-   |
-LL |     fn method1(&self) {}
-   |     ^^^^^^^^^^^^^^^^^ duplicate definitions for `method1`
-...
-LL |     fn method1(&self) {}
-   |     ----------------- other definition for `method1`
-   |
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0592`.
diff --git a/tests/ui/coherence/coherence-subtyping.rs b/tests/ui/coherence/coherence-subtyping.rs
index b3ed728a81c06..78974b6972a71 100644
--- a/tests/ui/coherence/coherence-subtyping.rs
+++ b/tests/ui/coherence/coherence-subtyping.rs
@@ -3,7 +3,6 @@
 //
 // Note: This scenario is currently accepted, but as part of the
 // universe transition (#56105) may eventually become an error.
-
 // check-pass
 
 trait TheTrait {
@@ -12,9 +11,6 @@ trait TheTrait {
 
 impl TheTrait for for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8 {}
 
-impl TheTrait for for<'a> fn(&'a u8, &'a u8) -> &'a u8 {
-    //~^ WARNING conflicting implementation
-    //~^^ WARNING this was previously accepted by the compiler but is being phased out
-}
+impl TheTrait for for<'a> fn(&'a u8, &'a u8) -> &'a u8 {}
 
 fn main() {}
diff --git a/tests/ui/coherence/coherence-subtyping.stderr b/tests/ui/coherence/coherence-subtyping.stderr
deleted file mode 100644
index 9d90019a50fd3..0000000000000
--- a/tests/ui/coherence/coherence-subtyping.stderr
+++ /dev/null
@@ -1,16 +0,0 @@
-warning: conflicting implementations of trait `TheTrait` for type `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
-  --> $DIR/coherence-subtyping.rs:15:1
-   |
-LL | impl TheTrait for for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8 {}
-   | ---------------------------------------------------------- first implementation here
-LL |
-LL | impl TheTrait for for<'a> fn(&'a u8, &'a u8) -> &'a u8 {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-   = note: `#[warn(coherence_leak_check)]` on by default
-
-warning: 1 warning emitted
-
diff --git a/tests/ui/coherence/coherence-wasm-bindgen.rs b/tests/ui/coherence/coherence-wasm-bindgen.rs
index ee09a72449be1..1de8b8c30fe0e 100644
--- a/tests/ui/coherence/coherence-wasm-bindgen.rs
+++ b/tests/ui/coherence/coherence-wasm-bindgen.rs
@@ -6,6 +6,8 @@
 // for `&A` (borrow).
 //
 // c.f. #56105
+//
+// check-pass
 
 #![deny(coherence_leak_check)]
 
@@ -29,9 +31,6 @@ impl<'a, 'b, A, R> IntoWasmAbi for &'a (dyn for<'x> Fn(&'x A) -> R + 'b)
 where
     A: RefFromWasmAbi,
     R: ReturnWasmAbi,
-{
-    //~^^^^^ ERROR conflicting implementation
-    //~| WARNING this was previously accepted
-}
+{}
 
 fn main() {}
diff --git a/tests/ui/coherence/coherence-wasm-bindgen.stderr b/tests/ui/coherence/coherence-wasm-bindgen.stderr
deleted file mode 100644
index 600cd42d8c69d..0000000000000
--- a/tests/ui/coherence/coherence-wasm-bindgen.stderr
+++ /dev/null
@@ -1,27 +0,0 @@
-error: conflicting implementations of trait `IntoWasmAbi` for type `&dyn Fn(&_) -> _`
-  --> $DIR/coherence-wasm-bindgen.rs:28:1
-   |
-LL | / impl<'a, 'b, A, R> IntoWasmAbi for &'a (dyn Fn(A) -> R + 'b)
-LL | | where
-LL | |     A: FromWasmAbi,
-LL | |     R: ReturnWasmAbi,
-   | |_____________________- first implementation here
-...
-LL | / impl<'a, 'b, A, R> IntoWasmAbi for &'a (dyn for<'x> Fn(&'x A) -> R + 'b)
-LL | | where
-LL | |     A: RefFromWasmAbi,
-LL | |     R: ReturnWasmAbi,
-   | |_____________________^ conflicting implementation for `&dyn Fn(&_) -> _`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: downstream crates may implement trait `FromWasmAbi` for type `&_`
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-note: the lint level is defined here
-  --> $DIR/coherence-wasm-bindgen.rs:10:9
-   |
-LL | #![deny(coherence_leak_check)]
-   |         ^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.explicit.stderr b/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.explicit.stderr
deleted file mode 100644
index 34f3904443c31..0000000000000
--- a/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.explicit.stderr
+++ /dev/null
@@ -1,19 +0,0 @@
-error: conflicting implementations of trait `FnMarker` for type `fn(&_)`
-  --> $DIR/negative-coherence-placeholder-region-constraints-on-unification.rs:21:1
-   |
-LL | impl<T: ?Sized + Marker> FnMarker for fn(T) {}
-   | ------------------------------------------- first implementation here
-LL | impl<T: ?Sized> FnMarker for fn(&T) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `fn(&_)`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-note: the lint level is defined here
-  --> $DIR/negative-coherence-placeholder-region-constraints-on-unification.rs:4:11
-   |
-LL | #![forbid(coherence_leak_check)]
-   |           ^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.rs b/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.rs
index 26d9d84d8f0c9..22d085273901e 100644
--- a/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.rs
+++ b/tests/ui/coherence/negative-coherence-placeholder-region-constraints-on-unification.rs
@@ -1,5 +1,5 @@
 // revisions: explicit implicit
-//[implicit] check-pass
+// check-pass
 
 #![forbid(coherence_leak_check)]
 #![feature(negative_impls, with_negative_coherence)]
@@ -19,7 +19,5 @@ trait FnMarker {}
 // as an assumption when proving `&'!0 T: Marker`...
 impl<T: ?Sized + Marker> FnMarker for fn(T) {}
 impl<T: ?Sized> FnMarker for fn(&T) {}
-//[explicit]~^ ERROR conflicting implementations of trait `FnMarker` for type `fn(&_)`
-//[explicit]~| WARN this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
 fn main() {}
diff --git a/tests/ui/const-generics/generic_const_exprs/typeid-equality-by-subtyping.stderr b/tests/ui/const-generics/generic_const_exprs/typeid-equality-by-subtyping.stderr
index 8cbd12654480a..77f93774f978b 100644
--- a/tests/ui/const-generics/generic_const_exprs/typeid-equality-by-subtyping.stderr
+++ b/tests/ui/const-generics/generic_const_exprs/typeid-equality-by-subtyping.stderr
@@ -7,5 +7,12 @@ LL |         WHAT_A_TYPE => 0,
    = note: the traits must be derived, manual `impl`s are not sufficient
    = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralEq.html for details
 
-error: aborting due to previous error
+error[E0277]: the trait bound `for<'a, 'b> fn(&'a (), &'b ()): WithAssoc<T>` is not satisfied
+  --> $DIR/typeid-equality-by-subtyping.rs:44:51
+   |
+LL | fn unsound<T>(x: <One as WithAssoc<T>>::Assoc) -> <Two as WithAssoc<T>>::Assoc
+   |                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `WithAssoc<T>` is not implemented for `for<'a, 'b> fn(&'a (), &'b ())`
+
+error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/const-generics/invariant.rs b/tests/ui/const-generics/invariant.rs
index 39d658be67d40..fb041b141bddd 100644
--- a/tests/ui/const-generics/invariant.rs
+++ b/tests/ui/const-generics/invariant.rs
@@ -12,8 +12,6 @@ impl SadBee for for<'a> fn(&'a ()) {
     const ASSOC: usize = 0;
 }
 impl SadBee for fn(&'static ()) {
-    //~^ WARNING conflicting implementations of trait
-    //~| WARNING this was previously accepted
     const ASSOC: usize = 100;
 }
 
diff --git a/tests/ui/const-generics/invariant.stderr b/tests/ui/const-generics/invariant.stderr
index aabe4c93b3624..06fcc84287469 100644
--- a/tests/ui/const-generics/invariant.stderr
+++ b/tests/ui/const-generics/invariant.stderr
@@ -1,26 +1,14 @@
-warning: conflicting implementations of trait `SadBee` for type `for<'a> fn(&'a ())`
-  --> $DIR/invariant.rs:14:1
-   |
-LL | impl SadBee for for<'a> fn(&'a ()) {
-   | ---------------------------------- first implementation here
-...
-LL | impl SadBee for fn(&'static ()) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `for<'a> fn(&'a ())`
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
-   = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
-   = note: `#[warn(coherence_leak_check)]` on by default
-
 error[E0308]: mismatched types
-  --> $DIR/invariant.rs:27:5
+  --> $DIR/invariant.rs:25:5
    |
+LL | ) -> &'static Foo<fn(&'static ())> {
+   |      ----------------------------- expected `&'static Foo<fn(&'static ())>` because of return type
 LL |     v
-   |     ^ one type is more general than the other
+   |     ^ types differ
    |
-   = note: expected reference `&Foo<fn(&())>`
-              found reference `&Foo<for<'a> fn(&'a ())>`
+   = note: expected reference `&'static Foo<fn(&'static ())>`
+              found reference `&'static Foo<for<'a> fn(&'a ())>`
 
-error: aborting due to previous error; 1 warning emitted
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs
index 921061916fc95..2ee9355657318 100644
--- a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs
@@ -32,5 +32,5 @@ fn main() {
     // NB. *However*, the reinstated leak-check gives an error here.
 
     foo::<()>();
-    //~^ ERROR implementation of `Trait` is not general enough
+    //~^ ERROR the trait bound `(): Trait<for<'b> fn(&'b u32)>` is not satisfied
 }
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
index 364b613fc7717..db9f6f356433d 100644
--- a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
@@ -1,11 +1,19 @@
-error: implementation of `Trait` is not general enough
-  --> $DIR/hrtb-exists-forall-trait-contravariant.rs:34:5
+error[E0277]: the trait bound `(): Trait<for<'b> fn(&'b u32)>` is not satisfied
+  --> $DIR/hrtb-exists-forall-trait-contravariant.rs:34:11
    |
 LL |     foo::<()>();
-   |     ^^^^^^^^^^^ implementation of `Trait` is not general enough
+   |           ^^ the trait `Trait<for<'b> fn(&'b u32)>` is not implemented for `()`
    |
-   = note: `()` must implement `Trait<for<'b> fn(&'b u32)>`
-   = note: ...but it actually implements `Trait<fn(&'0 u32)>`, for some specific lifetime `'0`
+   = help: the trait `Trait<fn(&u32)>` is implemented for `()`
+note: required by a bound in `foo`
+  --> $DIR/hrtb-exists-forall-trait-contravariant.rs:10:8
+   |
+LL | fn foo<T>()
+   |    --- required by a bound in this function
+LL | where
+LL |     T: Trait<for<'b> fn(&'b u32)>,
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs
index f95496a6c3cc0..fb5e51fd1e361 100644
--- a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs
@@ -2,8 +2,6 @@
 //
 // In particular, we test this pattern in trait solving, where it is not connected
 // to any part of the source code.
-//
-// check-pass
 
 trait Trait<T> {}
 
@@ -34,4 +32,5 @@ fn main() {
     //   This is because we can use `'static`.
 
     foo::<()>();
+    //~^ ERROR the trait bound `(): Trait<for<'b> fn(fn(&'b u32))>` is not satisfied [E0277]
 }
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.stderr
new file mode 100644
index 0000000000000..333dc59281ee5
--- /dev/null
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.stderr
@@ -0,0 +1,19 @@
+error[E0277]: the trait bound `(): Trait<for<'b> fn(fn(&'b u32))>` is not satisfied
+  --> $DIR/hrtb-exists-forall-trait-covariant.rs:34:11
+   |
+LL |     foo::<()>();
+   |           ^^ the trait `Trait<for<'b> fn(fn(&'b u32))>` is not implemented for `()`
+   |
+   = help: the trait `Trait<fn(fn(&u32))>` is implemented for `()`
+note: required by a bound in `foo`
+  --> $DIR/hrtb-exists-forall-trait-covariant.rs:10:8
+   |
+LL | fn foo<T>()
+   |    --- required by a bound in this function
+LL | where
+LL |     T: Trait<for<'b> fn(fn(&'b u32))>,
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs
index 9b9e4496a870d..a2ea7dbcf5163 100644
--- a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs
@@ -25,5 +25,5 @@ fn main() {
     //     yielding `fn(&!b u32)`, in a fresh universe U1
     //   - So we get `?a = !b` but the universe U0 assigned to `?a` cannot name `!b`.
 
-    foo::<()>(); //~ ERROR implementation of `Trait` is not general enough
+    foo::<()>(); //~ ERROR the trait bound `(): Trait<for<'b> fn(Cell<&'b u32>)>` is not satisfied
 }
diff --git a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr
index cb2ce8a4116aa..d612aebf0c9a3 100644
--- a/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr
@@ -1,11 +1,19 @@
-error: implementation of `Trait` is not general enough
-  --> $DIR/hrtb-exists-forall-trait-invariant.rs:28:5
+error[E0277]: the trait bound `(): Trait<for<'b> fn(Cell<&'b u32>)>` is not satisfied
+  --> $DIR/hrtb-exists-forall-trait-invariant.rs:28:11
    |
 LL |     foo::<()>();
-   |     ^^^^^^^^^^^ implementation of `Trait` is not general enough
+   |           ^^ the trait `Trait<for<'b> fn(Cell<&'b u32>)>` is not implemented for `()`
    |
-   = note: `()` must implement `Trait<for<'b> fn(Cell<&'b u32>)>`
-   = note: ...but it actually implements `Trait<fn(Cell<&'0 u32>)>`, for some specific lifetime `'0`
+   = help: the trait `Trait<fn(Cell<&u32>)>` is implemented for `()`
+note: required by a bound in `foo`
+  --> $DIR/hrtb-exists-forall-trait-invariant.rs:12:8
+   |
+LL | fn foo<T>()
+   |    --- required by a bound in this function
+LL | where
+LL |     T: Trait<for<'b> fn(Cell<&'b u32>)>,
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `foo`
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/higher-ranked/trait-bounds/issue-46989.rs b/tests/ui/higher-ranked/trait-bounds/issue-46989.rs
index 4a09f4be156e2..cd0f70fef05b7 100644
--- a/tests/ui/higher-ranked/trait-bounds/issue-46989.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-46989.rs
@@ -36,5 +36,5 @@ fn assert_foo<T: Foo>() {}
 
 fn main() {
     assert_foo::<fn(&i32)>();
-    //~^ ERROR implementation of `Foo` is not general enough
+    //~^ ERROR the trait bound `for<'a> fn(&'a i32): Foo` is not satisfied [E0277]
 }
diff --git a/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr b/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr
index 3f874220a2708..4421a08b20321 100644
--- a/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr
@@ -1,11 +1,16 @@
-error: implementation of `Foo` is not general enough
-  --> $DIR/issue-46989.rs:38:5
+error[E0277]: the trait bound `for<'a> fn(&'a i32): Foo` is not satisfied
+  --> $DIR/issue-46989.rs:38:18
    |
 LL |     assert_foo::<fn(&i32)>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
+   |                  ^^^^^^^^ the trait `Foo` is not implemented for `for<'a> fn(&'a i32)`
    |
-   = note: `Foo` would have to be implemented for the type `for<'a> fn(&'a i32)`
-   = note: ...but `Foo` is actually implemented for the type `fn(&'0 i32)`, for some specific lifetime `'0`
+   = help: the trait `Foo` is implemented for fn pointer `fn(A)`
+note: required by a bound in `assert_foo`
+  --> $DIR/issue-46989.rs:35:18
+   |
+LL | fn assert_foo<T: Foo>() {}
+   |                  ^^^ required by this bound in `assert_foo`
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/issues/issue-57362-2.rs b/tests/ui/issues/issue-57362-2.rs
index a0b0ea1d03893..de27fa2fa1885 100644
--- a/tests/ui/issues/issue-57362-2.rs
+++ b/tests/ui/issues/issue-57362-2.rs
@@ -19,7 +19,8 @@ impl<'a> X for fn(&'a ()) {
 }
 
 fn g() {
-    let x = <fn (&())>::make_g(); //~ ERROR the function
+    let x = <fn (&())>::make_g();
+    //~^ ERROR no function or associated item named `make_g`
 }
 
 fn main() {}
diff --git a/tests/ui/issues/issue-57362-2.stderr b/tests/ui/issues/issue-57362-2.stderr
index 37beb587d2767..a558f3c54feeb 100644
--- a/tests/ui/issues/issue-57362-2.stderr
+++ b/tests/ui/issues/issue-57362-2.stderr
@@ -1,11 +1,9 @@
-error[E0599]: the function or associated item `make_g` exists for fn pointer `fn(&())`, but its trait bounds were not satisfied
+error[E0599]: no function or associated item named `make_g` found for fn pointer `for<'a> fn(&'a ())` in the current scope
   --> $DIR/issue-57362-2.rs:22:25
    |
 LL |     let x = <fn (&())>::make_g();
-   |                         ^^^^^^ function or associated item cannot be called on `fn(&())` due to unsatisfied trait bounds
+   |                         ^^^^^^ function or associated item not found in `fn(&())`
    |
-   = note: the following trait bounds were not satisfied:
-           `for<'a> fn(&'a ()): X`
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `X` defines an item `make_g`, perhaps you need to implement it
   --> $DIR/issue-57362-2.rs:8:1
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-eq.rs b/tests/ui/lub-glb/old-lub-glb-hr-eq.rs
index fbf4aee02045d..fa13f0f6c3db7 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-eq.rs
+++ b/tests/ui/lub-glb/old-lub-glb-hr-eq.rs
@@ -3,8 +3,6 @@
 // error. However, now that we handle subtyping correctly, we no
 // longer get an error, because we recognize these two types as
 // equivalent!
-//
-// check-pass
 
 fn foo(x: fn(&u8, &u8), y: for<'a> fn(&'a u8, &'a u8)) {
     // The two types above are actually equivalent. With the older
@@ -12,7 +10,7 @@ fn foo(x: fn(&u8, &u8), y: for<'a> fn(&'a u8, &'a u8)) {
     // hence we gave errors. But now we've fixed that.
     let z = match 22 {
         0 => x,
-        _ => y,
+        _ => y, //~ ERROR `match` arms have incompatible types
     };
 }
 
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-eq.stderr b/tests/ui/lub-glb/old-lub-glb-hr-eq.stderr
new file mode 100644
index 0000000000000..8bf18d16dba18
--- /dev/null
+++ b/tests/ui/lub-glb/old-lub-glb-hr-eq.stderr
@@ -0,0 +1,18 @@
+error[E0308]: `match` arms have incompatible types
+  --> $DIR/old-lub-glb-hr-eq.rs:13:14
+   |
+LL |       let z = match 22 {
+   |  _____________-
+LL | |         0 => x,
+   | |              - this is found to be of type `for<'a, 'b> fn(&'a u8, &'b u8)`
+LL | |         _ => y,
+   | |              ^ types differ
+LL | |     };
+   | |_____- `match` arms have incompatible types
+   |
+   = note: expected fn pointer `for<'a, 'b> fn(&'a u8, &'b u8)`
+              found fn pointer `for<'a> fn(&'a u8, &'a u8)`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.baseleak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.baseleak.stderr
index 4448f9326cb94..e400b607fefd8 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.baseleak.stderr
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.baseleak.stderr
@@ -6,7 +6,7 @@ LL |       let z = match 22 {
 LL | |         0 => x,
    | |              - this is found to be of type `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
 LL | |         _ => y,
-   | |              ^ one type is more general than the other
+   | |              ^ types differ
 LL | |
 ...  |
 LL | |
@@ -15,6 +15,11 @@ LL | |     };
    |
    = note: expected fn pointer `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
               found fn pointer `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
+help: consider removing the ``
+   |
+LL -         _ => y,
+LL +         _ => y,
+   | 
 
 error: aborting due to previous error
 
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.basenoleak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.basenoleak.stderr
index 0d61311350e8c..e400b607fefd8 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.basenoleak.stderr
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.basenoleak.stderr
@@ -1,11 +1,25 @@
-error[E0308]: mismatched types
+error[E0308]: `match` arms have incompatible types
   --> $DIR/old-lub-glb-hr-noteq1.rs:17:14
    |
-LL |         _ => y,
-   |              ^ one type is more general than the other
+LL |       let z = match 22 {
+   |  _____________-
+LL | |         0 => x,
+   | |              - this is found to be of type `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
+LL | |         _ => y,
+   | |              ^ types differ
+LL | |
+...  |
+LL | |
+LL | |     };
+   | |_____- `match` arms have incompatible types
    |
    = note: expected fn pointer `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
               found fn pointer `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
+help: consider removing the ``
+   |
+LL -         _ => y,
+LL +         _ => y,
+   | 
 
 error: aborting due to previous error
 
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.leak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.leak.stderr
index dd0fdf3a12abf..4210229e5e90b 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.leak.stderr
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.leak.stderr
@@ -6,7 +6,7 @@ LL |       let z = match 22 {
 LL | |         0 => x,
    | |              - this is found to be of type `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
 LL | |         _ => y,
-   | |              ^ one type is more general than the other
+   | |              ^ types differ
 LL | |
 LL | |
 LL | |     };
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.noleak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.noleak.stderr
index cb046d0b0acad..4210229e5e90b 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.noleak.stderr
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.noleak.stderr
@@ -1,8 +1,16 @@
-error[E0308]: mismatched types
+error[E0308]: `match` arms have incompatible types
   --> $DIR/old-lub-glb-hr-noteq1.rs:14:14
    |
-LL |         _ => y,
-   |              ^ one type is more general than the other
+LL |       let z = match 22 {
+   |  _____________-
+LL | |         0 => x,
+   | |              - this is found to be of type `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
+LL | |         _ => y,
+   | |              ^ types differ
+LL | |
+LL | |
+LL | |     };
+   | |_____- `match` arms have incompatible types
    |
    = note: expected fn pointer `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
               found fn pointer `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.rs b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.rs
index 589119abb9b7c..89d1f975931ae 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq1.rs
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq1.rs
@@ -13,7 +13,7 @@ fn foo(x: for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8, y: for<'a> fn(&'a u8, &'a u8
         0 => x,
         _ => y,
         //[leak]~^ ERROR `match` arms have incompatible types
-        //[noleak]~^^ ERROR mismatched types
+        //[noleak]~^^ ERROR `match` arms have incompatible types
     };
 }
 
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq2.leak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.leak.stderr
index e54fcf068d8e8..e6532215ebae1 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq2.leak.stderr
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.leak.stderr
@@ -1,12 +1,13 @@
 error[E0308]: `match` arms have incompatible types
-  --> $DIR/old-lub-glb-hr-noteq2.rs:25:14
+  --> $DIR/old-lub-glb-hr-noteq2.rs:23:14
    |
 LL |       let z = match 22 {
    |  _____________-
 LL | |         0 => y,
    | |              - this is found to be of type `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
 LL | |         _ => x,
-   | |              ^ one type is more general than the other
+   | |              ^ types differ
+LL | |
 LL | |
 LL | |     };
    | |_____- `match` arms have incompatible types
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq2.noleak.stderr b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.noleak.stderr
new file mode 100644
index 0000000000000..e6532215ebae1
--- /dev/null
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.noleak.stderr
@@ -0,0 +1,20 @@
+error[E0308]: `match` arms have incompatible types
+  --> $DIR/old-lub-glb-hr-noteq2.rs:23:14
+   |
+LL |       let z = match 22 {
+   |  _____________-
+LL | |         0 => y,
+   | |              - this is found to be of type `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
+LL | |         _ => x,
+   | |              ^ types differ
+LL | |
+LL | |
+LL | |     };
+   | |_____- `match` arms have incompatible types
+   |
+   = note: expected fn pointer `for<'a> fn(&'a u8, &'a u8) -> &'a u8`
+              found fn pointer `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/lub-glb/old-lub-glb-hr-noteq2.rs b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.rs
index 9940c40da8134..b1635a133c6e3 100644
--- a/tests/ui/lub-glb/old-lub-glb-hr-noteq2.rs
+++ b/tests/ui/lub-glb/old-lub-glb-hr-noteq2.rs
@@ -14,8 +14,6 @@
 // revisions: leak noleak
 //[noleak] compile-flags: -Zno-leak-check
 
-//[noleak] check-pass
-
 fn foo(x: for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8, y: for<'a> fn(&'a u8, &'a u8) -> &'a u8) {
     // The two types above are not equivalent. With the older LUB/GLB
     // algorithm, this may have worked (I don't remember), but now it
@@ -24,6 +22,7 @@ fn foo(x: for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8, y: for<'a> fn(&'a u8, &'a u8
         0 => y,
         _ => x,
         //[leak]~^ ERROR `match` arms have incompatible types
+        //[noleak]~^^ ERROR `match` arms have incompatible types
     };
 }
 
diff --git a/tests/ui/mir/field-projection-invariant.rs b/tests/ui/mir/field-projection-invariant.rs
index b5d6add043cb9..ae87c172875bb 100644
--- a/tests/ui/mir/field-projection-invariant.rs
+++ b/tests/ui/mir/field-projection-invariant.rs
@@ -1,4 +1,3 @@
-// build-pass
 struct Inv<'a>(&'a mut &'a ());
 enum Foo<T> {
     Bar,
@@ -9,7 +8,7 @@ type Supertype = Foo<for<'a> fn(Inv<'a>, Inv<'a>)>;
 fn foo(x: Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>) {
     match x {
         Supertype::Bar => {}
-        Supertype::Var(x) => {}
+        Supertype::Var(x) => {} //~ ERROR mismatched types [E0308]
     }
 }
 
@@ -17,7 +16,7 @@ fn foo_nested(x: Foo<Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>>) {
     match x {
         Foo::Bar => {}
         Foo::Var(Supertype::Bar) => {}
-        Foo::Var(Supertype::Var(x)) => {}
+        Foo::Var(Supertype::Var(x)) => {} //~ ERROR mismatched types [E0308]
     }
 }
 
diff --git a/tests/ui/mir/field-projection-invariant.stderr b/tests/ui/mir/field-projection-invariant.stderr
new file mode 100644
index 0000000000000..14f03363b81d7
--- /dev/null
+++ b/tests/ui/mir/field-projection-invariant.stderr
@@ -0,0 +1,27 @@
+error[E0308]: mismatched types
+  --> $DIR/field-projection-invariant.rs:11:9
+   |
+LL |     match x {
+   |           - this expression has type `Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>`
+LL |         Supertype::Bar => {}
+LL |         Supertype::Var(x) => {}
+   |         ^^^^^^^^^^^^^^^^^ types differ
+   |
+   = note: expected enum `Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>`
+              found enum `Foo<for<'a> fn(Inv<'a>, Inv<'a>)>`
+
+error[E0308]: mismatched types
+  --> $DIR/field-projection-invariant.rs:19:18
+   |
+LL |     match x {
+   |           - this expression has type `Foo<Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>>`
+...
+LL |         Foo::Var(Supertype::Var(x)) => {}
+   |                  ^^^^^^^^^^^^^^^^^ types differ
+   |
+   = note: expected enum `Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>`
+              found enum `Foo<for<'a> fn(Inv<'a>, Inv<'a>)>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/mir/field-projection-mutating-context.stderr b/tests/ui/mir/field-projection-mutating-context.stderr
index 9b18b3427adff..8cf35860340d1 100644
--- a/tests/ui/mir/field-projection-mutating-context.stderr
+++ b/tests/ui/mir/field-projection-mutating-context.stderr
@@ -1,11 +1,11 @@
 error[E0308]: mismatched types
-  --> $DIR/field-projection-mutating-context.rs:9:13
+  --> $DIR/field-projection-mutating-context.rs:9:49
    |
 LL |     let Foo(ref mut y): Foo<fn(&'static str)> = x;
-   |             ^^^^^^^^^ one type is more general than the other
+   |                                                 ^ types differ
    |
-   = note: expected fn pointer `for<'a> fn(&'a str)`
-              found fn pointer `fn(&str)`
+   = note: expected struct `Foo<fn(&'static str)>`
+              found struct `Foo<for<'a> fn(&'a str)>`
 
 error: aborting due to previous error
 
diff --git a/tests/ui/nll/issue-57642-higher-ranked-subtype.rs b/tests/ui/nll/issue-57642-higher-ranked-subtype.rs
index eba859cde2206..fe55b9b003e0a 100644
--- a/tests/ui/nll/issue-57642-higher-ranked-subtype.rs
+++ b/tests/ui/nll/issue-57642-higher-ranked-subtype.rs
@@ -28,7 +28,7 @@ impl<T> Y for fn(T) {
 }
 
 fn higher_ranked_region_has_lost_its_binder() {
-    let x = <fn (&())>::make_g(); //~ ERROR the function
+    let x = <fn (&())>::make_g(); //~ ERROR no function
 }
 
 fn magical() {
diff --git a/tests/ui/nll/issue-57642-higher-ranked-subtype.stderr b/tests/ui/nll/issue-57642-higher-ranked-subtype.stderr
index d1e94bc702cae..679bab63e8531 100644
--- a/tests/ui/nll/issue-57642-higher-ranked-subtype.stderr
+++ b/tests/ui/nll/issue-57642-higher-ranked-subtype.stderr
@@ -1,11 +1,9 @@
-error[E0599]: the function or associated item `make_g` exists for fn pointer `fn(&())`, but its trait bounds were not satisfied
+error[E0599]: no function or associated item named `make_g` found for fn pointer `for<'a> fn(&'a ())` in the current scope
   --> $DIR/issue-57642-higher-ranked-subtype.rs:31:25
    |
 LL |     let x = <fn (&())>::make_g();
-   |                         ^^^^^^ function or associated item cannot be called on `fn(&())` due to unsatisfied trait bounds
+   |                         ^^^^^^ function or associated item not found in `fn(&())`
    |
-   = note: the following trait bounds were not satisfied:
-           `for<'a> fn(&'a ()): X`
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `X` defines an item `make_g`, perhaps you need to implement it
   --> $DIR/issue-57642-higher-ranked-subtype.rs:4:1
diff --git a/tests/ui/nll/issue-97997.rs b/tests/ui/nll/issue-97997.rs
index c64e720b12f7f..d8213d04bef89 100644
--- a/tests/ui/nll/issue-97997.rs
+++ b/tests/ui/nll/issue-97997.rs
@@ -11,6 +11,5 @@ fn main() {
     impls_foo(foo as fn(i32));
 
     <fn(&u8) as Foo>::ASSOC;
-    //~^ ERROR implementation of `Foo` is not general enough
-    //~| ERROR implementation of `Foo` is not general enough
+    //~^ ERROR the trait bound `for<'a> fn(&'a u8): Foo` is not satisfied [E0277]
 }
diff --git a/tests/ui/nll/issue-97997.stderr b/tests/ui/nll/issue-97997.stderr
index 89eaf77adf063..9540cc4816b4f 100644
--- a/tests/ui/nll/issue-97997.stderr
+++ b/tests/ui/nll/issue-97997.stderr
@@ -1,21 +1,11 @@
-error: implementation of `Foo` is not general enough
-  --> $DIR/issue-97997.rs:13:5
+error[E0277]: the trait bound `for<'a> fn(&'a u8): Foo` is not satisfied
+  --> $DIR/issue-97997.rs:13:6
    |
 LL |     <fn(&u8) as Foo>::ASSOC;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
+   |      ^^^^^^^ the trait `Foo` is not implemented for `for<'a> fn(&'a u8)`
    |
-   = note: `Foo` would have to be implemented for the type `for<'a> fn(&'a u8)`
-   = note: ...but `Foo` is actually implemented for the type `fn(&'0 u8)`, for some specific lifetime `'0`
+   = help: the trait `Foo` is implemented for fn pointer `fn(T)`
 
-error: implementation of `Foo` is not general enough
-  --> $DIR/issue-97997.rs:13:5
-   |
-LL |     <fn(&u8) as Foo>::ASSOC;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
-   |
-   = note: `Foo` would have to be implemented for the type `for<'a> fn(&'a u8)`
-   = note: ...but `Foo` is actually implemented for the type `fn(&'0 u8)`, for some specific lifetime `'0`
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs b/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs
index 92730341c1110..683186d7c33df 100644
--- a/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs
+++ b/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs
@@ -1,13 +1,9 @@
-// Test an interesting corner case that ought to be legal (though the
-// current code actually gets it wrong, see below): a fn that takes
+// Test an interesting corner case that has previously been legal: a fn that takes
 // two arguments that are references with the same lifetime is in fact
 // equivalent to a fn that takes two references with distinct
 // lifetimes. This is true because the two functions can call one
 // another -- effectively, the single lifetime `'a` is just inferred
 // to be the intersection of the two distinct lifetimes.
-//
-// check-pass
-// compile-flags:-Zno-leak-check
 
 use std::cell::Cell;
 
@@ -17,7 +13,8 @@ fn make_cell_aa() -> Cell<for<'a> fn(&'a u32, &'a u32)> {
 
 fn aa_eq_ab() {
     let a: Cell<for<'a, 'b> fn(&'a u32, &'b u32)> = make_cell_aa();
+    //~^ ERROR mismatched types
     drop(a);
 }
 
-fn main() { }
+fn main() {}
diff --git a/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.stderr b/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.stderr
new file mode 100644
index 0000000000000..4ff0024036382
--- /dev/null
+++ b/tests/ui/nll/relate_tys/hr-fn-aau-eq-abu.stderr
@@ -0,0 +1,14 @@
+error[E0308]: mismatched types
+  --> $DIR/hr-fn-aau-eq-abu.rs:15:53
+   |
+LL |     let a: Cell<for<'a, 'b> fn(&'a u32, &'b u32)> = make_cell_aa();
+   |            --------------------------------------   ^^^^^^^^^^^^^^ types differ
+   |            |
+   |            expected due to this
+   |
+   = note: expected struct `Cell<for<'a, 'b> fn(&'a u32, &'b u32)>`
+              found struct `Cell<for<'a> fn(&'a u32, &'a u32)>`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.rs b/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.rs
index 05e2ea047f65a..d76fd4a42f307 100644
--- a/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.rs
+++ b/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.rs
@@ -28,7 +28,5 @@ impl<T> Y for fn(T) {
 
 fn main() {
     let _x = <fn(&())>::make_f();
-    //~^ ERROR implementation of `Y` is not general enough
-    //~| ERROR implementation of `Y` is not general enough
-    //~| ERROR implementation of `Y` is not general enough
+    //~^ ERROR no function or associated item named `make_f`
 }
diff --git a/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.stderr b/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.stderr
index 804071a3e6f77..fad1280464933 100644
--- a/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.stderr
+++ b/tests/ui/nll/relate_tys/impl-fn-ignore-binder-via-bottom.stderr
@@ -1,31 +1,16 @@
-error: implementation of `Y` is not general enough
-  --> $DIR/impl-fn-ignore-binder-via-bottom.rs:30:14
+error[E0599]: no function or associated item named `make_f` found for fn pointer `for<'a> fn(&'a ())` in the current scope
+  --> $DIR/impl-fn-ignore-binder-via-bottom.rs:30:25
    |
 LL |     let _x = <fn(&())>::make_f();
-   |              ^^^^^^^^^^^^^^^^^^^ implementation of `Y` is not general enough
+   |                         ^^^^^^ function or associated item not found in `fn(&())`
    |
-   = note: `Y` would have to be implemented for the type `for<'a> fn(&'a ())`
-   = note: ...but `Y` is actually implemented for the type `fn(&'0 ())`, for some specific lifetime `'0`
-
-error: implementation of `Y` is not general enough
-  --> $DIR/impl-fn-ignore-binder-via-bottom.rs:30:14
-   |
-LL |     let _x = <fn(&())>::make_f();
-   |              ^^^^^^^^^^^^^^^^^^^ implementation of `Y` is not general enough
-   |
-   = note: `Y` would have to be implemented for the type `for<'a> fn(&'a ())`
-   = note: ...but `Y` is actually implemented for the type `fn(&'0 ())`, for some specific lifetime `'0`
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: implementation of `Y` is not general enough
-  --> $DIR/impl-fn-ignore-binder-via-bottom.rs:30:14
-   |
-LL |     let _x = <fn(&())>::make_f();
-   |              ^^^^^^^^^^^^^^^^^^^ implementation of `Y` is not general enough
+   = help: items from traits can only be used if the trait is implemented and in scope
+note: `Y` defines an item `make_f`, perhaps you need to implement it
+  --> $DIR/impl-fn-ignore-binder-via-bottom.rs:16:1
    |
-   = note: `Y` would have to be implemented for the type `for<'a> fn(&'a ())`
-   = note: ...but `Y` is actually implemented for the type `fn(&'0 ())`, for some specific lifetime `'0`
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+LL | trait Y {
+   | ^^^^^^^
 
-error: aborting due to 3 previous errors
+error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0599`.
diff --git a/tests/ui/panic-handler/panic-handler-bad-signature-1.stderr b/tests/ui/panic-handler/panic-handler-bad-signature-1.stderr
index 85555c43906e8..5ef83076fa4e2 100644
--- a/tests/ui/panic-handler/panic-handler-bad-signature-1.stderr
+++ b/tests/ui/panic-handler/panic-handler-bad-signature-1.stderr
@@ -1,8 +1,8 @@
 error[E0308]: `#[panic_handler]` function has wrong type
-  --> $DIR/panic-handler-bad-signature-1.rs:9:16
+  --> $DIR/panic-handler-bad-signature-1.rs:9:1
    |
 LL | fn panic(info: PanicInfo) -> () {}
-   |                ^^^^^^^^^ expected `&PanicInfo<'_>`, found `PanicInfo<'_>`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ
    |
    = note: expected signature `for<'a, 'b> fn(&'a PanicInfo<'b>) -> !`
               found signature `for<'a> fn(PanicInfo<'a>)`
diff --git a/tests/ui/panic-handler/panic-handler-bad-signature-2.stderr b/tests/ui/panic-handler/panic-handler-bad-signature-2.stderr
index 84eba2a5a63c2..e60e8d2d8cacf 100644
--- a/tests/ui/panic-handler/panic-handler-bad-signature-2.stderr
+++ b/tests/ui/panic-handler/panic-handler-bad-signature-2.stderr
@@ -2,7 +2,7 @@ error[E0308]: `#[panic_handler]` function has wrong type
   --> $DIR/panic-handler-bad-signature-2.rs:9:1
    |
 LL | fn panic(info: &'static PanicInfo) -> !
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ
    |
    = note: expected signature `for<'a, 'b> fn(&'a PanicInfo<'b>) -> _`
               found signature `for<'a> fn(&'static PanicInfo<'a>) -> _`
diff --git a/tests/ui/panic-handler/panic-handler-bad-signature-3.stderr b/tests/ui/panic-handler/panic-handler-bad-signature-3.stderr
index cdf55ab6534ea..b6f1c49165861 100644
--- a/tests/ui/panic-handler/panic-handler-bad-signature-3.stderr
+++ b/tests/ui/panic-handler/panic-handler-bad-signature-3.stderr
@@ -2,7 +2,7 @@ error[E0308]: `#[panic_handler]` function has wrong type
   --> $DIR/panic-handler-bad-signature-3.rs:9:1
    |
 LL | fn panic() -> ! {
-   | ^^^^^^^^^^^^^^^ incorrect number of function parameters
+   | ^^^^^^^^^^^^^^^ types differ
    |
    = note: expected signature `for<'a, 'b> fn(&'a PanicInfo<'b>) -> _`
               found signature `fn() -> _`
diff --git a/tests/ui/panic-handler/panic-handler-bad-signature-5.stderr b/tests/ui/panic-handler/panic-handler-bad-signature-5.stderr
index 20c17587590ca..1a84c52666b33 100644
--- a/tests/ui/panic-handler/panic-handler-bad-signature-5.stderr
+++ b/tests/ui/panic-handler/panic-handler-bad-signature-5.stderr
@@ -2,7 +2,7 @@ error[E0308]: `#[panic_handler]` function has wrong type
   --> $DIR/panic-handler-bad-signature-5.rs:9:1
    |
 LL | fn panic(info: &PanicInfo<'static>) -> !
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ
    |
    = note: expected signature `for<'a, 'b> fn(&'a PanicInfo<'b>) -> _`
               found signature `for<'a> fn(&'a PanicInfo<'static>) -> _`
diff --git a/tests/ui/traits/new-solver/member-constraints-in-root-universe.rs b/tests/ui/traits/new-solver/member-constraints-in-root-universe.rs
index 97c4430586447..3de167dc7bd36 100644
--- a/tests/ui/traits/new-solver/member-constraints-in-root-universe.rs
+++ b/tests/ui/traits/new-solver/member-constraints-in-root-universe.rs
@@ -10,7 +10,7 @@ impl Trait for for<'a> fn(&'a u8, &'a u8) {
 }
 
 // argument is necessary to create universes before registering the hidden type.
-fn test<'a>(_: <fn(&u8, &u8) as Trait>::Ty) -> impl Sized {
+fn test<'a>(_: <for<'b> fn(&'b u8, &'b u8) as Trait>::Ty) -> impl Sized {
     "hidden type is `&'?0 str` with '?0 member of ['static,]"
 }
 
diff --git a/tests/ui/type-alias-impl-trait/normalize-hidden-types.current.stderr b/tests/ui/type-alias-impl-trait/normalize-hidden-types.current.stderr
index dd2737c706d6b..2bb472b11d3a5 100644
--- a/tests/ui/type-alias-impl-trait/normalize-hidden-types.current.stderr
+++ b/tests/ui/type-alias-impl-trait/normalize-hidden-types.current.stderr
@@ -29,14 +29,12 @@ LL |     type Opaque = impl Sized;
    |                   ---------- the expected opaque type
 ...
 LL |         let _: Opaque = dyn_hoops::<u8>(0);
-   |                ------   ^^^^^^^^^^^^^^^^^^ expected opaque type, found `*const dyn FnOnce(())`
+   |                ------   ^^^^^^^^^^^^^^^^^^ types differ
    |                |
    |                expected due to this
    |
    = note: expected opaque type `typeck::Opaque`
               found raw pointer `*const (dyn FnOnce(()) + 'static)`
-   = help: consider constraining the associated type `<u8 as Trait>::Gat<'_>` to `()` or calling a method that returns `<u8 as Trait>::Gat<'_>`
-   = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
 
 error: concrete type differs from previous defining opaque type use
   --> $DIR/normalize-hidden-types.rs:54:25