From 7927f0919f178c099f2824f691cfc79065bb419d Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Thu, 22 Sep 2022 21:01:13 +0200
Subject: [PATCH 1/2] add regression test for miri issue 2433

---
 .../miri/tests/pass/issues/issue-miri-2433.rs | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 src/tools/miri/tests/pass/issues/issue-miri-2433.rs

diff --git a/src/tools/miri/tests/pass/issues/issue-miri-2433.rs b/src/tools/miri/tests/pass/issues/issue-miri-2433.rs
new file mode 100644
index 00000000000..de719df0f1f
--- /dev/null
+++ b/src/tools/miri/tests/pass/issues/issue-miri-2433.rs
@@ -0,0 +1,22 @@
+#![feature(type_alias_impl_trait)]
+
+trait T { type Item; }
+
+type Alias<'a> = impl T<Item = &'a ()>;
+
+struct S;
+impl<'a> T for &'a S {
+    type Item = &'a ();
+}
+
+fn filter_positive<'a>() -> Alias<'a> {
+    &S
+}
+
+fn with_positive(fun: impl Fn(Alias<'_>)) {
+    fun(filter_positive());
+}
+
+fn main() {
+    with_positive(|_| ());
+}

From a7cdfafafb78ddddaaf5ab0c7e14cefc71d3a1db Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Thu, 22 Sep 2022 21:01:23 +0200
Subject: [PATCH 2/2] make Miri build in stage 0

---
 src/tools/miri/cargo-miri/src/main.rs | 1 +
 src/tools/miri/src/lib.rs             | 1 +
 2 files changed, 2 insertions(+)

diff --git a/src/tools/miri/cargo-miri/src/main.rs b/src/tools/miri/cargo-miri/src/main.rs
index 331c4c9c2b0..da891ef0772 100644
--- a/src/tools/miri/cargo-miri/src/main.rs
+++ b/src/tools/miri/cargo-miri/src/main.rs
@@ -1,3 +1,4 @@
+#![cfg_attr(bootstrap, feature(let_else))]
 #![allow(clippy::useless_format, clippy::derive_partial_eq_without_eq, rustc::internal)]
 
 #[macro_use]
diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
index 6006d6c89db..cda27beab30 100644
--- a/src/tools/miri/src/lib.rs
+++ b/src/tools/miri/src/lib.rs
@@ -10,6 +10,7 @@
 #![feature(is_some_with)]
 #![feature(nonzero_ops)]
 #![feature(local_key_cell_methods)]
+#![cfg_attr(bootstrap, feature(let_else))]
 // Configure clippy and other lints
 #![allow(
     clippy::collapsible_else_if,