diff --git a/rust-toolchain b/rust-toolchain
index 33ff8b03da2..0057e2f370a 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2023-07-01"
+channel = "nightly-2023-10-22"
 components = ["llvm-tools", "rustc-dev"]
diff --git a/src/comment.rs b/src/comment.rs
index f7957321464..7da0f79bd09 100644
--- a/src/comment.rs
+++ b/src/comment.rs
@@ -2074,28 +2074,6 @@ fn run_test(
             expected_line_start: &str,
         ) {
             let block = ItemizedBlock::new(test_input).unwrap();
-<<<<<<< HEAD
-            assert_eq!(1, block.lines.len(), "test_input: {:?}", test_input);
-            assert_eq!(
-                expected_line, &block.lines[0],
-                "test_input: {:?}",
-                test_input
-            );
-            assert_eq!(
-                expected_indent, block.indent,
-                "test_input: {:?}",
-                test_input
-            );
-            assert_eq!(
-                expected_opener, &block.opener,
-                "test_input: {:?}",
-                test_input
-            );
-            assert_eq!(
-                expected_line_start, &block.line_start,
-                "test_input: {:?}",
-                test_input
-=======
             assert_eq!(1, block.lines.len(), "test_input: {test_input:?}");
             assert_eq!(expected_line, &block.lines[0], "test_input: {test_input:?}");
             assert_eq!(expected_indent, block.indent, "test_input: {test_input:?}");
@@ -2103,7 +2081,6 @@ fn run_test(
             assert_eq!(
                 expected_line_start, &block.line_start,
                 "test_input: {test_input:?}"
->>>>>>> upstream/master
             );
         }
 
@@ -2155,23 +2132,15 @@ fn test_itemized_block_nonobvious_markers_are_rejected() {
             // https://spec.commonmark.org/0.30 says: "A start number may not be negative":
             "-1. Not a list item.",
             "-1 Not a list item.",
-<<<<<<< HEAD
-=======
             // Marker without prefix are not recognized as item markers:
             ".   Not a list item.",
             ")   Not a list item.",
->>>>>>> upstream/master
         ];
         for line in test_inputs.iter() {
             let maybe_block = ItemizedBlock::new(line);
             assert!(
                 maybe_block.is_none(),
-<<<<<<< HEAD
-                "The following line shouldn't be classified as a list item: {}",
-                line
-=======
                 "The following line shouldn't be classified as a list item: {line}"
->>>>>>> upstream/master
             );
         }
     }
diff --git a/src/expr.rs b/src/expr.rs
index 878e2b7d6d0..acde8809329 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -132,7 +132,7 @@ pub(crate) fn format_expr(
         ast::ExprKind::Tup(ref items) => {
             rewrite_tuple(context, items.iter(), expr.span, shape, items.len() == 1)
         }
-        ast::ExprKind::Let(ref pat, ref expr, _span) => rewrite_let(context, shape, pat, expr),
+        ast::ExprKind::Let(ref pat, ref expr, _span, _) => rewrite_let(context, shape, pat, expr),
         ast::ExprKind::If(..)
         | ast::ExprKind::ForLoop(..)
         | ast::ExprKind::Loop(..)
diff --git a/src/pairs.rs b/src/pairs.rs
index 9dac20d3699..07c05193739 100644
--- a/src/pairs.rs
+++ b/src/pairs.rs
@@ -274,7 +274,7 @@ impl<'a, 'b> PairList<'a, 'b, ast::Expr> {
     fn let_chain_count(&self) -> usize {
         self.list
             .iter()
-            .filter(|(expr, _)| matches!(expr.kind, ast::ExprKind::Let(_, _, _)))
+            .filter(|(expr, _)| matches!(expr.kind, ast::ExprKind::Let(..)))
             .count()
     }
 
@@ -284,7 +284,7 @@ fn can_rewrite_let_chain_single_line(&self) -> bool {
         }
 
         let fist_item_is_ident = is_ident(self.list[0].0);
-        let second_item_is_let_chain = matches!(self.list[1].0.kind, ast::ExprKind::Let(_, _, _));
+        let second_item_is_let_chain = matches!(self.list[1].0.kind, ast::ExprKind::Let(..));
 
         fist_item_is_ident && second_item_is_let_chain
     }