Auto merge of #100868 - Dylan-DPC:rollup-a1hfi1r, r=Dylan-DPC

Rollup of 5 pull requests

Successful merges:

 - #93162 (Std module docs improvements)
 - #99386 (Add tests that check `Vec::retain` predicate execution order.)
 - #99915 (Recover keywords in trait bounds)
 - #100694 (Migrate rustc_ast_passes diagnostics to `SessionDiagnostic` and translatable messages (first part))
 - #100757 (Catch overflow early)

Failed merges:

 - #99917 (Move Error trait into core)

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

8 files changed, 262 insertions, 10 deletions

diff --git a/src/test/ui/issues/issue-23122-2.stderr b/src/test/ui/issues/issue-23122-2.stderr
index 3d8e7b96918..f6cda3de5c7 100644
--- a/src/test/ui/issues/issue-23122-2.stderr
+++ b/src/test/ui/issues/issue-23122-2.stderr
@@ -1,15 +1,10 @@
-error[E0275]: overflow evaluating the requirement `<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<T as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next: Sized`
+error[E0275]: overflow evaluating the requirement `<T as Next>::Next`
   --> $DIR/issue-23122-2.rs:10:17
    |
 LL |     type Next = <GetNext<T::Next> as Next>::Next;
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_23122_2`)
-note: required for `GetNext<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<T as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next as Next>::Next>` to implement `Next`
-  --> $DIR/issue-23122-2.rs:9:15
-   |
-LL | impl<T: Next> Next for GetNext<T> {
-   |               ^^^^     ^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/parser/kw-in-trait-bounds.rs b/src/test/ui/parser/kw-in-trait-bounds.rs
new file mode 100644
index 00000000000..fa037e5937d
--- /dev/null
+++ b/src/test/ui/parser/kw-in-trait-bounds.rs
@@ -0,0 +1,47 @@
+// edition:2018
+
+fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+//~^ ERROR expected identifier, found keyword `fn`
+//~| ERROR expected identifier, found keyword `fn`
+//~| ERROR expected identifier, found keyword `fn`
+//~| ERROR cannot find trait `r#fn` in this scope
+//~| ERROR cannot find trait `r#fn` in this scope
+//~| ERROR cannot find trait `r#fn` in this scope
+//~| HELP  a trait with a similar name exists
+//~| HELP  a trait with a similar name exists
+//~| HELP  a trait with a similar name exists
+//~| HELP  escape `fn` to use it as an identifier
+//~| HELP  escape `fn` to use it as an identifier
+//~| HELP  escape `fn` to use it as an identifier
+where
+G: fn(),
+    //~^ ERROR expected identifier, found keyword `fn`
+    //~| ERROR cannot find trait `r#fn` in this scope
+    //~| HELP  a trait with a similar name exists
+    //~| HELP  escape `fn` to use it as an identifier
+{}
+
+fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+//~^ ERROR expected identifier, found keyword `struct`
+//~| ERROR expected identifier, found keyword `struct`
+//~| ERROR expected identifier, found keyword `struct`
+//~| ERROR cannot find trait `r#struct` in this scope
+//~| ERROR cannot find trait `r#struct` in this scope
+//~| ERROR cannot find trait `r#struct` in this scope
+//~| HELP  a trait with a similar name exists
+//~| HELP  a trait with a similar name exists
+//~| HELP  a trait with a similar name exists
+//~| HELP  escape `struct` to use it as an identifier
+//~| HELP  escape `struct` to use it as an identifier
+//~| HELP  escape `struct` to use it as an identifier
+where
+    B: struct,
+    //~^ ERROR expected identifier, found keyword `struct`
+    //~| ERROR cannot find trait `r#struct` in this scope
+    //~| HELP  a trait with a similar name exists
+    //~| HELP  escape `struct` to use it as an identifier
+{}
+
+trait Struct {}
+
+fn main() {}
diff --git a/src/test/ui/parser/kw-in-trait-bounds.stderr b/src/test/ui/parser/kw-in-trait-bounds.stderr
new file mode 100644
index 00000000000..28196c7ce2d
--- /dev/null
+++ b/src/test/ui/parser/kw-in-trait-bounds.stderr
@@ -0,0 +1,171 @@
+error: expected identifier, found keyword `fn`
+  --> $DIR/kw-in-trait-bounds.rs:3:10
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |          ^^ expected identifier, found keyword
+   |
+help: escape `fn` to use it as an identifier
+   |
+LL | fn _f<F: r#fn(), G>(_: impl fn(), _: &dyn fn())
+   |          ++
+
+error: expected identifier, found keyword `fn`
+  --> $DIR/kw-in-trait-bounds.rs:3:27
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |                           ^^ expected identifier, found keyword
+   |
+help: escape `fn` to use it as an identifier
+   |
+LL | fn _f<F: fn(), G>(_: impl r#fn(), _: &dyn fn())
+   |                           ++
+
+error: expected identifier, found keyword `fn`
+  --> $DIR/kw-in-trait-bounds.rs:3:41
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |                                         ^^ expected identifier, found keyword
+   |
+help: escape `fn` to use it as an identifier
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn r#fn())
+   |                                         ++
+
+error: expected identifier, found keyword `fn`
+  --> $DIR/kw-in-trait-bounds.rs:17:4
+   |
+LL | G: fn(),
+   |    ^^ expected identifier, found keyword
+   |
+help: escape `fn` to use it as an identifier
+   |
+LL | G: r#fn(),
+   |    ++
+
+error: expected identifier, found keyword `struct`
+  --> $DIR/kw-in-trait-bounds.rs:24:10
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |          ^^^^^^ expected identifier, found keyword
+   |
+help: escape `struct` to use it as an identifier
+   |
+LL | fn _g<A: r#struct, B>(_: impl struct, _: &dyn struct)
+   |          ++
+
+error: expected identifier, found keyword `struct`
+  --> $DIR/kw-in-trait-bounds.rs:24:29
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |                             ^^^^^^ expected identifier, found keyword
+   |
+help: escape `struct` to use it as an identifier
+   |
+LL | fn _g<A: struct, B>(_: impl r#struct, _: &dyn struct)
+   |                             ++
+
+error: expected identifier, found keyword `struct`
+  --> $DIR/kw-in-trait-bounds.rs:24:45
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |                                             ^^^^^^ expected identifier, found keyword
+   |
+help: escape `struct` to use it as an identifier
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn r#struct)
+   |                                             ++
+
+error: expected identifier, found keyword `struct`
+  --> $DIR/kw-in-trait-bounds.rs:38:8
+   |
+LL |     B: struct,
+   |        ^^^^^^ expected identifier, found keyword
+   |
+help: escape `struct` to use it as an identifier
+   |
+LL |     B: r#struct,
+   |        ++
+
+error[E0405]: cannot find trait `r#fn` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:3:10
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |          ^^ help: a trait with a similar name exists (notice the capitalization): `Fn`
+   |
+  ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args>: FnMut<Args> {
+   | ------------------------------- similarly named trait `Fn` defined here
+
+error[E0405]: cannot find trait `r#fn` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:17:4
+   |
+LL | G: fn(),
+   |    ^^ help: a trait with a similar name exists (notice the capitalization): `Fn`
+   |
+  ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args>: FnMut<Args> {
+   | ------------------------------- similarly named trait `Fn` defined here
+
+error[E0405]: cannot find trait `r#fn` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:3:27
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |                           ^^ help: a trait with a similar name exists (notice the capitalization): `Fn`
+   |
+  ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args>: FnMut<Args> {
+   | ------------------------------- similarly named trait `Fn` defined here
+
+error[E0405]: cannot find trait `r#fn` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:3:41
+   |
+LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
+   |                                         ^^ help: a trait with a similar name exists (notice the capitalization): `Fn`
+   |
+  ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args>: FnMut<Args> {
+   | ------------------------------- similarly named trait `Fn` defined here
+
+error[E0405]: cannot find trait `r#struct` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:24:10
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |          ^^^^^^ help: a trait with a similar name exists (notice the capitalization): `Struct`
+...
+LL | trait Struct {}
+   | ------------ similarly named trait `Struct` defined here
+
+error[E0405]: cannot find trait `r#struct` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:38:8
+   |
+LL |     B: struct,
+   |        ^^^^^^ help: a trait with a similar name exists (notice the capitalization): `Struct`
+...
+LL | trait Struct {}
+   | ------------ similarly named trait `Struct` defined here
+
+error[E0405]: cannot find trait `r#struct` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:24:29
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |                             ^^^^^^ help: a trait with a similar name exists (notice the capitalization): `Struct`
+...
+LL | trait Struct {}
+   | ------------ similarly named trait `Struct` defined here
+
+error[E0405]: cannot find trait `r#struct` in this scope
+  --> $DIR/kw-in-trait-bounds.rs:24:45
+   |
+LL | fn _g<A: struct, B>(_: impl struct, _: &dyn struct)
+   |                                             ^^^^^^ help: a trait with a similar name exists (notice the capitalization): `Struct`
+...
+LL | trait Struct {}
+   | ------------ similarly named trait `Struct` defined here
+
+error: aborting due to 16 previous errors
+
+For more information about this error, try `rustc --explain E0405`.
diff --git a/src/test/ui/recursion/issue-83150.stderr b/src/test/ui/recursion/issue-83150.stderr
index 07f82847568..32f25faf3e8 100644
--- a/src/test/ui/recursion/issue-83150.stderr
+++ b/src/test/ui/recursion/issue-83150.stderr
@@ -9,9 +9,11 @@ LL |     func(&mut iter.map(|x| x + 1))
    = note: `#[warn(unconditional_recursion)]` on by default
    = help: a `loop` may express intention better if this is on purpose
 
-error[E0275]: overflow evaluating the requirement `Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>: Iterator`
+error[E0275]: overflow evaluating the requirement `<std::ops::Range<u8> as Iterator>::Item`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_83150`)
+   = note: required for `Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>` to implement `Iterator`
+   = note: 64 redundant requirements hidden
    = note: required for `&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>` to implement `Iterator`
 
 error: aborting due to previous error; 1 warning emitted
diff --git a/src/test/ui/recursion/issue-95134.rs b/src/test/ui/recursion/issue-95134.rs
new file mode 100644
index 00000000000..adc9c6ee2d9
--- /dev/null
+++ b/src/test/ui/recursion/issue-95134.rs
@@ -0,0 +1,28 @@
+// build-fail
+// compile-flags: -Copt-level=0
+//~^^ ERROR overflow evaluating the requirement
+
+pub fn encode_num<Writer: ExampleWriter>(n: u32, mut writer: Writer) -> Result<(), Writer::Error> {
+    if n > 15 {
+        encode_num(n / 16, &mut writer)?;
+    }
+    Ok(())
+}
+
+pub trait ExampleWriter {
+    type Error;
+}
+
+impl<'a, T: ExampleWriter> ExampleWriter for &'a mut T {
+    type Error = T::Error;
+}
+
+struct EmptyWriter;
+
+impl ExampleWriter for EmptyWriter {
+    type Error = ();
+}
+
+fn main() {
+    encode_num(69, &mut EmptyWriter).unwrap();
+}
diff --git a/src/test/ui/recursion/issue-95134.stderr b/src/test/ui/recursion/issue-95134.stderr
new file mode 100644
index 00000000000..57a498694b7
--- /dev/null
+++ b/src/test/ui/recursion/issue-95134.stderr
@@ -0,0 +1,7 @@
+error[E0275]: overflow evaluating the requirement `<EmptyWriter as ExampleWriter>::Error`
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_95134`)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0275`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/without-tilde.rs b/src/test/ui/rfc-2632-const-trait-impl/without-tilde.rs
index e8b26154549..d63381b5f2c 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/without-tilde.rs
+++ b/src/test/ui/rfc-2632-const-trait-impl/without-tilde.rs
@@ -3,4 +3,4 @@
 #![feature(const_trait_impl)]
 
 struct S<T: const Tr>;
-//~^ ERROR expected one of `!`, `(`, `,`, `=`, `>`, `?`, `for`, `~`, lifetime, or path
+//~^ ERROR const bounds must start with `~`
diff --git a/src/test/ui/rfc-2632-const-trait-impl/without-tilde.stderr b/src/test/ui/rfc-2632-const-trait-impl/without-tilde.stderr
index b6b77ac4a2f..31300354a57 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/without-tilde.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/without-tilde.stderr
@@ -1,8 +1,10 @@
-error: expected one of `!`, `(`, `,`, `=`, `>`, `?`, `for`, `~`, lifetime, or path, found keyword `const`
+error: const bounds must start with `~`
   --> $DIR/without-tilde.rs:5:13
    |
 LL | struct S<T: const Tr>;
-   |             ^^^^^ expected one of 10 possible tokens
+   |             -^^^^
+   |             |
+   |             help: add `~`: `~`
 
 error: aborting due to previous error