Auto merge of #111881 - lcnr:leak-check, r=nikomatsakis,jackh726

refactor and cleanup the leak check, add it to new solver

ended up being a bit more involved than I wanted but is hopefully still easy enough to review as a single PR, can split it into separate ones otherwise.

this can be reviewed commit by commit:
a473d55cdb9284aa2b01282d1b529a2a4d26547b 31a686646534ca006d906ec757ece4e771d6f973 949039c107852a5e36361c08b62821a0613656f5 242917bf5170d9a723c6c8e23e9d9d0c2fa8dc9d ed2b25a7aa28be3184be9e3022c2796a30eaad87 are all pretty straightforward.

03dd83b4c3f4ff27558f5c8ab859bd9f83db1d04 makes it easier to refactor coherence in a later commit, see the commit description, cc `@oli-obk`

4fe311d807a77b6270f384e41689bf5d58f46aec I don't quite remember what we wanted to test here, this definitely doesn't test that the occurs check doesn't cause incorrect errors in coherence, also cc `@oli-obk` here. I may end up writing a new test for this myself later.

5c200d88a91b75bd0875b973150655bd581ef97a is the main refactor of the leak check, changing it to take the `outer_universe` instead of getting it from a snapshot. Using a snapshot requires us to be in a probe which we aren't in the new solver, it also just feels dirty as snapshots don't really have anything to do with universes.

with all of this cfc230d54188d9c7ed867a9a0d1f51be77b485f9 is now kind of trivial.

r? `@nikomatsakis`

124 files changed, 112 insertions, 32 deletions

diff --git a/tests/ui/coherence/coherence-inherited-subtyping.re.stderr b/tests/ui/coherence/coherence-inherited-subtyping.re.stderr
deleted file mode 100644
index 4701bc0b139..00000000000
--- a/tests/ui/coherence/coherence-inherited-subtyping.re.stderr
+++ /dev/null
@@ -1,14 +0,0 @@
-error[E0592]: duplicate definitions with name `method1`
-  --> $DIR/coherence-inherited-subtyping.rs:14:5
-   |
-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-inherited-subtyping.rs b/tests/ui/coherence/coherence-inherited-subtyping.rs
index 8587eb77950..f35cd2103da 100644
--- a/tests/ui/coherence/coherence-inherited-subtyping.rs
+++ b/tests/ui/coherence/coherence-inherited-subtyping.rs
@@ -4,8 +4,6 @@
 // Note: This scenario is currently accepted, but as part of the
 // universe transition (#56105) may eventually become an error.
 
-// revisions: old re
-
 struct Foo<T> {
     t: T,
 }
diff --git a/tests/ui/coherence/coherence-inherited-subtyping.old.stderr b/tests/ui/coherence/coherence-inherited-subtyping.stderr
index 4701bc0b139..f60b2aa2735 100644
--- a/tests/ui/coherence/coherence-inherited-subtyping.old.stderr
+++ b/tests/ui/coherence/coherence-inherited-subtyping.stderr
@@ -1,5 +1,5 @@
 error[E0592]: duplicate definitions with name `method1`
-  --> $DIR/coherence-inherited-subtyping.rs:14:5
+  --> $DIR/coherence-inherited-subtyping.rs:12:5
    |
 LL |     fn method1(&self) {}
    |     ^^^^^^^^^^^^^^^^^ duplicate definitions for `method1`
diff --git a/tests/ui/coinduction/canonicalization-rerun.rs b/tests/ui/coinduction/canonicalization-rerun.rs
index b10ba3a810f..c68895fc4e6 100644
--- a/tests/ui/coinduction/canonicalization-rerun.rs
+++ b/tests/ui/coinduction/canonicalization-rerun.rs
@@ -1,6 +1,6 @@
 // check-pass
-// revisions: old new
-//[new] compile-flags: -Ztrait-solver=next
+// revisions: old next
+//[next] compile-flags: -Ztrait-solver=next
 
 // If we use canonical goals during trait solving we have to reevaluate
 // the root goal of a cycle until we hit a fixpoint.
diff --git a/tests/ui/higher-rank-trait-bounds/issue-95230.rs b/tests/ui/higher-rank-trait-bounds/issue-95230.rs
deleted file mode 100644
index 769b6a92537..00000000000
--- a/tests/ui/higher-rank-trait-bounds/issue-95230.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-// revisions: old new
-//[new] compile-flags: -Ztrait-solver=next
-//[old] check-pass
-//[new] known-bug: #109764
-
-
-pub struct Bar
-where
-    for<'a> &'a mut Self:;
-
-fn main() {}
diff --git a/tests/ui/higher-lifetime-bounds.rs b/tests/ui/higher-ranked/higher-lifetime-bounds.rs
index f3393347d90..f3393347d90 100644
--- a/tests/ui/higher-lifetime-bounds.rs
+++ b/tests/ui/higher-ranked/higher-lifetime-bounds.rs
diff --git a/tests/ui/higher-lifetime-bounds.stderr b/tests/ui/higher-ranked/higher-lifetime-bounds.stderr
index bc6d2288cdf..bc6d2288cdf 100644
--- a/tests/ui/higher-lifetime-bounds.stderr
+++ b/tests/ui/higher-ranked/higher-lifetime-bounds.stderr
diff --git a/tests/ui/higher-ranked/leak-check-in-selection.rs b/tests/ui/higher-ranked/leak-check-in-selection.rs
new file mode 100644
index 00000000000..e8d6cff856c
--- /dev/null
+++ b/tests/ui/higher-ranked/leak-check-in-selection.rs
@@ -0,0 +1,24 @@
+// run-pass
+// revisions: old next
+//[next] compile-flags: -Ztrait-solver=next
+#![allow(coherence_leak_check)]
+
+trait Trait: Sized {
+    fn is_higher_ranked(self) -> bool;
+}
+
+impl Trait for for<'a> fn(&'a ()) {
+    fn is_higher_ranked(self) -> bool {
+        true
+    }
+}
+impl<'a> Trait for fn(&'a ()) {
+    fn is_higher_ranked(self) -> bool {
+        false
+    }
+}
+
+fn main() {
+    let x: for<'a> fn(&'a ()) = |&()| ();
+    assert!(x.is_higher_ranked());
+}
diff --git a/tests/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.stderr b/tests/ui/higher-ranked/subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.stderr
index b7264c7e933..b7264c7e933 100644
--- a/tests/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.stderr
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.stderr
diff --git a/tests/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.stderr b/tests/ui/higher-ranked/subtype/hr-subtype.bound_a_vs_free_x.stderr
index 2355979b0f9..2355979b0f9 100644
--- a/tests/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.stderr
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.bound_a_vs_free_x.stderr
diff --git a/tests/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.stderr b/tests/ui/higher-ranked/subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.stderr
index a73c03feb87..a73c03feb87 100644
--- a/tests/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.stderr
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.stderr
diff --git a/tests/ui/hr-subtype/hr-subtype.free_inv_x_vs_free_inv_y.stderr b/tests/ui/higher-ranked/subtype/hr-subtype.free_inv_x_vs_free_inv_y.stderr
index 31d36d7168b..31d36d7168b 100644
--- a/tests/ui/hr-subtype/hr-subtype.free_inv_x_vs_free_inv_y.stderr
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.free_inv_x_vs_free_inv_y.stderr
diff --git a/tests/ui/hr-subtype/hr-subtype.free_x_vs_free_y.stderr b/tests/ui/higher-ranked/subtype/hr-subtype.free_x_vs_free_y.stderr
index 269cde54c7e..269cde54c7e 100644
--- a/tests/ui/hr-subtype/hr-subtype.free_x_vs_free_y.stderr
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.free_x_vs_free_y.stderr
diff --git a/tests/ui/hr-subtype/hr-subtype.rs b/tests/ui/higher-ranked/subtype/hr-subtype.rs
index c770e0de85c..c770e0de85c 100644
--- a/tests/ui/hr-subtype/hr-subtype.rs
+++ b/tests/ui/higher-ranked/subtype/hr-subtype.rs
diff --git a/tests/ui/hr-subtype/placeholder-pattern-fail.rs b/tests/ui/higher-ranked/subtype/placeholder-pattern-fail.rs
index bd4533e0433..bd4533e0433 100644
--- a/tests/ui/hr-subtype/placeholder-pattern-fail.rs
+++ b/tests/ui/higher-ranked/subtype/placeholder-pattern-fail.rs
diff --git a/tests/ui/hr-subtype/placeholder-pattern-fail.stderr b/tests/ui/higher-ranked/subtype/placeholder-pattern-fail.stderr
index 73b0a317364..73b0a317364 100644
--- a/tests/ui/hr-subtype/placeholder-pattern-fail.stderr
+++ b/tests/ui/higher-ranked/subtype/placeholder-pattern-fail.stderr
diff --git a/tests/ui/hr-subtype/placeholder-pattern.rs b/tests/ui/higher-ranked/subtype/placeholder-pattern.rs
index 061e66e54d2..061e66e54d2 100644
--- a/tests/ui/hr-subtype/placeholder-pattern.rs
+++ b/tests/ui/higher-ranked/subtype/placeholder-pattern.rs
diff --git a/tests/ui/hr-subtype/return-static.rs b/tests/ui/higher-ranked/subtype/return-static.rs
index 6455854f34d..6455854f34d 100644
--- a/tests/ui/hr-subtype/return-static.rs
+++ b/tests/ui/higher-ranked/subtype/return-static.rs
diff --git a/tests/ui/higher-rank-trait-bounds/complex.rs b/tests/ui/higher-ranked/trait-bounds/complex.rs
index 8cdfe247e02..8cdfe247e02 100644
--- a/tests/ui/higher-rank-trait-bounds/complex.rs
+++ b/tests/ui/higher-ranked/trait-bounds/complex.rs
diff --git a/tests/ui/higher-rank-trait-bounds/due-to-where-clause.rs b/tests/ui/higher-ranked/trait-bounds/due-to-where-clause.rs
index 1afd15613b5..1afd15613b5 100644
--- a/tests/ui/higher-rank-trait-bounds/due-to-where-clause.rs
+++ b/tests/ui/higher-ranked/trait-bounds/due-to-where-clause.rs
diff --git a/tests/ui/higher-rank-trait-bounds/due-to-where-clause.stderr b/tests/ui/higher-ranked/trait-bounds/due-to-where-clause.stderr
index 520938a6335..520938a6335 100644
--- a/tests/ui/higher-rank-trait-bounds/due-to-where-clause.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/due-to-where-clause.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/fn-ptr.classic.stderr b/tests/ui/higher-ranked/trait-bounds/fn-ptr.classic.stderr
index 9af6bc45c7a..9af6bc45c7a 100644
--- a/tests/ui/higher-rank-trait-bounds/fn-ptr.classic.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/fn-ptr.classic.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/fn-ptr.rs b/tests/ui/higher-ranked/trait-bounds/fn-ptr.rs
index 853160f9612..853160f9612 100644
--- a/tests/ui/higher-rank-trait-bounds/fn-ptr.rs
+++ b/tests/ui/higher-ranked/trait-bounds/fn-ptr.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hang-on-deeply-nested-dyn.rs b/tests/ui/higher-ranked/trait-bounds/hang-on-deeply-nested-dyn.rs
index d34b7a29623..d34b7a29623 100644
--- a/tests/ui/higher-rank-trait-bounds/hang-on-deeply-nested-dyn.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hang-on-deeply-nested-dyn.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hang-on-deeply-nested-dyn.stderr b/tests/ui/higher-ranked/trait-bounds/hang-on-deeply-nested-dyn.stderr
index 3662cbfb9ba..a9d649b8285 100644
--- a/tests/ui/higher-rank-trait-bounds/hang-on-deeply-nested-dyn.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hang-on-deeply-nested-dyn.stderr
@@ -14,7 +14,7 @@ LL |       f
    |       ^ expected `&dyn Fn(&dyn Fn(&dyn Fn(&...)))`, found `&dyn Fn(u32)`
    |
    = note: expected reference `&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&dyn Fn(&...)))))))))))`
-           the full type name has been written to '$TEST_BUILD_DIR/higher-rank-trait-bounds/hang-on-deeply-nested-dyn/hang-on-deeply-nested-dyn.long-type-hash.txt'
+           the full type name has been written to '$TEST_BUILD_DIR/higher-ranked/trait-bounds/hang-on-deeply-nested-dyn/hang-on-deeply-nested-dyn.long-type-hash.txt'
               found reference `&dyn Fn(u32)`
 
 error: aborting due to previous error
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-binder-levels-in-object-types.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-binder-levels-in-object-types.rs
index cc766c0605c..cc766c0605c 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-binder-levels-in-object-types.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-binder-levels-in-object-types.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-cache-issue-54302.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-cache-issue-54302.rs
index a20d03c7747..a20d03c7747 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-cache-issue-54302.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-cache-issue-54302.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-cache-issue-54302.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-cache-issue-54302.stderr
index f014eab8601..f014eab8601 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-cache-issue-54302.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-cache-issue-54302.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-conflate-regions.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-conflate-regions.rs
index e83686404a3..e83686404a3 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-conflate-regions.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-conflate-regions.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-conflate-regions.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-conflate-regions.stderr
index 46f5308dd87..46f5308dd87 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-conflate-regions.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-conflate-regions.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-in-receiver.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-in-receiver.rs
index 05d3e1a434e..05d3e1a434e 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-in-receiver.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-in-receiver.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-in-receiver.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-in-receiver.stderr
index fa391ecba8a..fa391ecba8a 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-in-receiver.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-in-receiver.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-object-types-in-closures.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-object-types-in-closures.rs
index 8431226a3ec..8431226a3ec 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-debruijn-object-types-in-closures.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-debruijn-object-types-in-closures.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-fn.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-fn.rs
index 56780237618..56780237618 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-fn.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-fn.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-fn.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-fn.stderr
index 9914783d976..9914783d976 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-fn.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-fn.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-contravariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs
index 921061916fc..921061916fc 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-contravariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-contravariant.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
index 364b613fc77..364b613fc77 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-contravariant.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-covariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs
index f95496a6c3c..f95496a6c3c 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-covariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-covariant.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-invariant.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs
index 9b9e4496a87..9b9e4496a87 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-invariant.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-invariant.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr
index cb2ce8a4116..cb2ce8a4116 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-exists-forall-trait-invariant.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-exists-forall-trait-invariant.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-fn-like-trait-object.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-fn-like-trait-object.rs
index ff84ad9d298..ff84ad9d298 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-fn-like-trait-object.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-fn-like-trait-object.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-fn-like-trait.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-fn-like-trait.rs
index afab9986ce2..afab9986ce2 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-fn-like-trait.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-fn-like-trait.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits-transitive.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits-transitive.rs
index f9ae1429ee4..f9ae1429ee4 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits-transitive.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits-transitive.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits-transitive.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits-transitive.stderr
index b1b8ffa8c54..b1b8ffa8c54 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits-transitive.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits-transitive.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits.rs
index 48ebe5017aa..48ebe5017aa 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits.stderr
index 7f96909b6e7..7f96909b6e7 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-higher-ranker-supertraits.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-identity-fn-borrows.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-identity-fn-borrows.rs
index 89fc4705a78..89fc4705a78 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-identity-fn-borrows.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-identity-fn-borrows.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-identity-fn-borrows.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-identity-fn-borrows.stderr
index 25af011e3fc..25af011e3fc 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-identity-fn-borrows.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-identity-fn-borrows.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-just-for-static.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-just-for-static.rs
index 8fb4218f8a4..8fb4218f8a4 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-just-for-static.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-just-for-static.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-just-for-static.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-just-for-static.stderr
index 31e11e12835..31e11e12835 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-just-for-static.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-just-for-static.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-malformed-lifetime-generics.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-malformed-lifetime-generics.rs
index 4b096be591a..4b096be591a 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-malformed-lifetime-generics.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-malformed-lifetime-generics.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-malformed-lifetime-generics.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-malformed-lifetime-generics.stderr
index e8f6d63b5ab..e8f6d63b5ab 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-malformed-lifetime-generics.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-malformed-lifetime-generics.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-opt-in-copy.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-opt-in-copy.rs
index 04519f11600..04519f11600 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-opt-in-copy.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-opt-in-copy.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-parse.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-parse.rs
index 1fab9758c5c..1fab9758c5c 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-parse.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-parse.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.polonius.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.polonius.stderr
index a94c80eb30b..a94c80eb30b 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.polonius.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.polonius.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.rs
index d45fa183c0c..d45fa183c0c 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.stderr
index 727b9e6bec8..727b9e6bec8 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-perfect-forwarding.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-perfect-forwarding.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-precedence-of-plus-where-clause.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-precedence-of-plus-where-clause.rs
index 42247798f66..42247798f66 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-precedence-of-plus-where-clause.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-precedence-of-plus-where-clause.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-precedence-of-plus.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-precedence-of-plus.rs
index 6834c392d4e..6834c392d4e 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-precedence-of-plus.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-precedence-of-plus.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-resolve-lifetime.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-resolve-lifetime.rs
index b97fdf4df50..b97fdf4df50 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-resolve-lifetime.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-resolve-lifetime.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-trait-object-paren-notation.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-trait-object-paren-notation.rs
index d8c726cdd71..d8c726cdd71 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-trait-object-paren-notation.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-trait-object-paren-notation.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-trait-object-passed-to-closure.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-trait-object-passed-to-closure.rs
index 41ebb3f5a14..41ebb3f5a14 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-trait-object-passed-to-closure.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-trait-object-passed-to-closure.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-type-outlives.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-type-outlives.rs
index 88d396101db..88d396101db 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-type-outlives.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-type-outlives.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-unboxed-closure-trait.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-unboxed-closure-trait.rs
index a4a8a5ac6cc..a4a8a5ac6cc 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-unboxed-closure-trait.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-unboxed-closure-trait.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-wrong-kind.rs b/tests/ui/higher-ranked/trait-bounds/hrtb-wrong-kind.rs
index 1a9bb252340..1a9bb252340 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-wrong-kind.rs
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-wrong-kind.rs
diff --git a/tests/ui/higher-rank-trait-bounds/hrtb-wrong-kind.stderr b/tests/ui/higher-ranked/trait-bounds/hrtb-wrong-kind.stderr
index 765ea9f7854..765ea9f7854 100644
--- a/tests/ui/higher-rank-trait-bounds/hrtb-wrong-kind.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/hrtb-wrong-kind.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/issue-100689.rs b/tests/ui/higher-ranked/trait-bounds/issue-100689.rs
index 2db7f8a354c..2db7f8a354c 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-100689.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-100689.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-102899.rs b/tests/ui/higher-ranked/trait-bounds/issue-102899.rs
index 952b81584f3..952b81584f3 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-102899.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-102899.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-30786.rs b/tests/ui/higher-ranked/trait-bounds/issue-30786.rs
index 4a6399c8f62..4a6399c8f62 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-30786.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-30786.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-30786.stderr b/tests/ui/higher-ranked/trait-bounds/issue-30786.stderr
index 6ec34d11a7e..f32ba57200d 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-30786.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-30786.stderr
@@ -31,7 +31,7 @@ LL | pub struct Filter<S, F> {
 LL |     let count = filter.countx();
    |                        ^^^^^^ method cannot be called due to unsatisfied trait bounds
    |
-   = note: the full type name has been written to '$TEST_BUILD_DIR/higher-rank-trait-bounds/issue-30786/issue-30786.long-type-hash.txt'
+   = note: the full type name has been written to '$TEST_BUILD_DIR/higher-ranked/trait-bounds/issue-30786/issue-30786.long-type-hash.txt'
 note: the following trait bounds were not satisfied:
       `&'a mut &Filter<Map<Repeat, for<'a> fn(&'a u64) -> &'a u64 {identity::<u64>}>, [closure@$DIR/issue-30786.rs:131:30: 131:37]>: Stream`
       `&'a mut &mut Filter<Map<Repeat, for<'a> fn(&'a u64) -> &'a u64 {identity::<u64>}>, [closure@$DIR/issue-30786.rs:131:30: 131:37]>: Stream`
diff --git a/tests/ui/higher-rank-trait-bounds/issue-36139-normalize-closure-sig.rs b/tests/ui/higher-ranked/trait-bounds/issue-36139-normalize-closure-sig.rs
index 2d49151ffcc..2d49151ffcc 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-36139-normalize-closure-sig.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-36139-normalize-closure-sig.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-39292.rs b/tests/ui/higher-ranked/trait-bounds/issue-39292.rs
index 968cf08916f..968cf08916f 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-39292.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-39292.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-42114.rs b/tests/ui/higher-ranked/trait-bounds/issue-42114.rs
index 01515fdc9d2..01515fdc9d2 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-42114.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-42114.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-43623.rs b/tests/ui/higher-ranked/trait-bounds/issue-43623.rs
index cedcf7c361c..cedcf7c361c 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-43623.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-43623.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-46989.rs b/tests/ui/higher-ranked/trait-bounds/issue-46989.rs
index 4a09f4be156..4a09f4be156 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-46989.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-46989.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-46989.stderr b/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr
index 3f874220a27..3f874220a27 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-46989.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-46989.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/issue-57639.rs b/tests/ui/higher-ranked/trait-bounds/issue-57639.rs
index 392e7233b56..392e7233b56 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-57639.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-57639.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-58451.rs b/tests/ui/higher-ranked/trait-bounds/issue-58451.rs
index 6006a108c5c..6006a108c5c 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-58451.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-58451.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-58451.stderr b/tests/ui/higher-ranked/trait-bounds/issue-58451.stderr
index 0f051be2128..0f051be2128 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-58451.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-58451.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/issue-59311.rs b/tests/ui/higher-ranked/trait-bounds/issue-59311.rs
index 3ad548450e5..3ad548450e5 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-59311.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-59311.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-59311.stderr b/tests/ui/higher-ranked/trait-bounds/issue-59311.stderr
index c01ab8e347c..c01ab8e347c 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-59311.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-59311.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/issue-60283.rs b/tests/ui/higher-ranked/trait-bounds/issue-60283.rs
index 05315b3f9f5..05315b3f9f5 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-60283.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-60283.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-62203-hrtb-ice.rs b/tests/ui/higher-ranked/trait-bounds/issue-62203-hrtb-ice.rs
index e70f6fc3430..e70f6fc3430 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-62203-hrtb-ice.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-62203-hrtb-ice.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-62203-hrtb-ice.stderr b/tests/ui/higher-ranked/trait-bounds/issue-62203-hrtb-ice.stderr
index 4d470ae7022..4d470ae7022 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-62203-hrtb-ice.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-62203-hrtb-ice.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/issue-88446.rs b/tests/ui/higher-ranked/trait-bounds/issue-88446.rs
index 571b8531757..571b8531757 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-88446.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-88446.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-88586-hr-self-outlives-in-trait-def.rs b/tests/ui/higher-ranked/trait-bounds/issue-88586-hr-self-outlives-in-trait-def.rs
index 92b7c5deb81..92b7c5deb81 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-88586-hr-self-outlives-in-trait-def.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-88586-hr-self-outlives-in-trait-def.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-90177.rs b/tests/ui/higher-ranked/trait-bounds/issue-90177.rs
index b151a9d3ab6..b151a9d3ab6 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-90177.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-90177.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-95034.rs b/tests/ui/higher-ranked/trait-bounds/issue-95034.rs
index af4946a187f..af4946a187f 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-95034.rs
+++ b/tests/ui/higher-ranked/trait-bounds/issue-95034.rs
diff --git a/tests/ui/higher-rank-trait-bounds/issue-95230.new.stderr b/tests/ui/higher-ranked/trait-bounds/issue-95230.next.stderr
index d4bc5b67220..d4bc5b67220 100644
--- a/tests/ui/higher-rank-trait-bounds/issue-95230.new.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/issue-95230.next.stderr
diff --git a/tests/ui/higher-ranked/trait-bounds/issue-95230.rs b/tests/ui/higher-ranked/trait-bounds/issue-95230.rs
new file mode 100644
index 00000000000..49a1584d54e
--- /dev/null
+++ b/tests/ui/higher-ranked/trait-bounds/issue-95230.rs
@@ -0,0 +1,11 @@
+// revisions: old next
+//[next] compile-flags: -Ztrait-solver=next
+//[old] check-pass
+//[next] known-bug: #109764
+
+
+pub struct Bar
+where
+    for<'a> &'a mut Self:;
+
+fn main() {}
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-44005.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-44005.rs
index f255eac0c4b..f255eac0c4b 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-44005.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-44005.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-56556.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-56556.rs
index 4d38cb19e9b..4d38cb19e9b 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-56556.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-56556.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-1.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-1.rs
index c6f29fa5908..c6f29fa5908 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-1.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-1.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-2.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-2.rs
index 00205473291..00205473291 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-2.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-2.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-3.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-3.rs
index d84e30f4984..d84e30f4984 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-3.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-3.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-3.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-3.stderr
index b30dd36d2ad..b30dd36d2ad 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-3.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-3.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-4.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-4.rs
index 8c2a59868ca..8c2a59868ca 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-4.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-4.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-5.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-5.rs
index 03f257a029c..03f257a029c 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-5.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-5.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-6.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-6.rs
index 74a4785e478..74a4785e478 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-62529-6.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-62529-6.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-70120.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-70120.rs
index 3ced40230f0..3ced40230f0 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-70120.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-70120.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.migrate.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.migrate.stderr
index 0f38f8e3283..0f38f8e3283 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.migrate.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.migrate.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.rs
index 1d90226a3f4..1d90226a3f4 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.stderr
index 4ef96cd9541..4ef96cd9541 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-71955.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-71955.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-74261.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-74261.rs
index 93ccb42684c..93ccb42684c 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-74261.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-74261.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-76956.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-76956.rs
index 583470080a2..583470080a2 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-76956.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-76956.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-80706.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-80706.rs
index 00a866f220b..00a866f220b 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-80706.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-80706.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-80956.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-80956.rs
index 6316ceea156..6316ceea156 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-80956.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-80956.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-81809.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-81809.rs
index f6ab9c203b5..f6ab9c203b5 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-81809.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-81809.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-85455.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-85455.rs
index 8aa29926d4f..8aa29926d4f 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-85455.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-85455.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-85455.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-85455.stderr
index 3240518fbbe..3240518fbbe 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-85455.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-85455.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89118.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89118.rs
index fffb54f86ca..fffb54f86ca 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89118.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89118.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89118.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89118.stderr
index edef6ccd34e..edef6ccd34e 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89118.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89118.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89436.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89436.rs
index f7e467b3786..f7e467b3786 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-89436.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-89436.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90612.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90612.rs
index effc329456d..effc329456d 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90612.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90612.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90638.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90638.rs
index 628b5cba104..628b5cba104 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90638.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90638.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90875.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90875.rs
index ffd6857d84a..ffd6857d84a 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90875.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90875.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90950.rs
index ab9d9a7ce6f..ab9d9a7ce6f 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90950.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90950.stderr
index 5be33bccdc3..5be33bccdc3 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/issue-90950.stderr
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.rs b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/norm-before-method-resolution.rs
index 7693b118247..7693b118247 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.rs
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/norm-before-method-resolution.rs
diff --git a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr
index 73388a72574..73388a72574 100644
--- a/tests/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr
+++ b/tests/ui/higher-ranked/trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr
diff --git a/tests/ui/traits/new-solver/leak-check-coinductive-cycle.rs b/tests/ui/traits/new-solver/leak-check-coinductive-cycle.rs
new file mode 100644
index 00000000000..1f7d4a49c90
--- /dev/null
+++ b/tests/ui/traits/new-solver/leak-check-coinductive-cycle.rs
@@ -0,0 +1,33 @@
+// check-pass
+// compile-flags: -Ztrait-solver=next
+#![feature(rustc_attrs)]
+
+#[rustc_coinductive]
+trait Trait<T> {}
+impl<'a, 'b, T> Trait<T> for (&'a (), &'b ())
+where
+    'b: 'a,
+    &'a (): Trait<T>,
+{}
+
+impl Trait<i32> for &'static () {}
+impl<'a> Trait<u32> for &'a ()
+where
+    for<'b> (&'a (), &'b ()): Trait<u32>,
+{}
+
+
+fn impls_trait<T: Trait<U>, U>() {}
+
+fn main() {
+    // This infers to `impls_trait::<(&'static (), &'static ()), i32>();`
+    //
+    // In the first attempt we have 2 candidates for `&'a (): Trait<_>`
+    // and we get ambiguity. The result is therefore ambiguity with a `'b: 'a`
+    // constraint. The next attempt then uses that provisional result when
+    // trying to apply `impl<'a> Trait<u32> for &'a ()`. This means we get a
+    // `for<'b> 'b: 'a` bound which fails the leak check. Because of this we
+    // end up with a single impl for `&'a (): Trait<_>` which infers `_` to `i32`
+    // and succeeds.
+    impls_trait::<(&(), &()), _>();
+}
diff --git a/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.rs b/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.rs
new file mode 100644
index 00000000000..39b3d535ad4
--- /dev/null
+++ b/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.rs
@@ -0,0 +1,25 @@
+// When checking whether these two impls overlap, we could detect that we
+// would require the hidden type of `TAIT` to be equal to both `u32` and `i32`
+// and therefore accept them as disjoint. That is annoying to implement with
+// the current system because we would have to add the following to each
+// returning branch in coherence.
+//
+//    let _ = infcx.take_opaque_types();
+//
+// @lcnr: Because of this I decided to not bother and cause this to fail instead.
+// In the future we can definitely modify the compiler to accept this
+// again.
+#![feature(type_alias_impl_trait)]
+
+trait Trait {}
+
+type TAIT = impl Sized;
+
+impl Trait for (TAIT, TAIT) {}
+
+impl Trait for (u32, i32) {}
+//~^ ERROR conflicting implementations of trait `Trait` for type `(TAIT, TAIT)`
+
+fn define() -> TAIT {}
+
+fn main() {}
diff --git a/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.stderr b/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.stderr
new file mode 100644
index 00000000000..f2aee798608
--- /dev/null
+++ b/tests/ui/type-alias-impl-trait/coherence_different_hidden_ty.stderr
@@ -0,0 +1,12 @@
+error[E0119]: conflicting implementations of trait `Trait` for type `(TAIT, TAIT)`
+  --> $DIR/coherence_different_hidden_ty.rs:20:1
+   |
+LL | impl Trait for (TAIT, TAIT) {}
+   | --------------------------- first implementation here
+LL |
+LL | impl Trait for (u32, i32) {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(TAIT, TAIT)`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/type-alias-impl-trait/coherence_generalization.rs b/tests/ui/type-alias-impl-trait/coherence_generalization.rs
index 5c9ad9498b6..679b2b0f188 100644
--- a/tests/ui/type-alias-impl-trait/coherence_generalization.rs
+++ b/tests/ui/type-alias-impl-trait/coherence_generalization.rs
@@ -1,5 +1,7 @@
 // check-pass
 
+// FIXME(type_alias_impl_trait): What does this test? This needs a comment
+// explaining what we're worried about here.
 #![feature(type_alias_impl_trait)]
 trait Trait {}
 type Opaque<T> = impl Sized;