4 files changed, 13 insertions, 9 deletions
diff --git a/compiler/rustc_index/src/bit_set.rs b/compiler/rustc_index/src/bit_set.rs
index 777112442..15179392c 100644
--- a/compiler/rustc_index/src/bit_set.rs
+++ b/compiler/rustc_index/src/bit_set.rs
@@ -209,7 +209,7 @@ impl<T: Idx> BitSet<T> {
             self.words[start_word_index] |= !(start_mask - 1);
             // And all trailing bits (i.e. from 0..=end) in the end word,
             // including the end.
-            self.words[end_word_index] |= end_mask | end_mask - 1;
+            self.words[end_word_index] |= end_mask | (end_mask - 1);
         } else {
             self.words[start_word_index] |= end_mask | (end_mask - start_mask);
         }
@@ -1091,7 +1091,7 @@ impl<T: Idx> ToString for BitSet<T> {
                 assert!(mask <= 0xFF);
                 let byte = word & mask;
 
-                result.push_str(&format!("{}{:02x}", sep, byte));
+                result.push_str(&format!("{sep}{byte:02x}"));
 
                 if remain <= 8 {
                     break;
diff --git a/compiler/rustc_index/src/interval.rs b/compiler/rustc_index/src/interval.rs
index 3592fb330..d809740c6 100644
--- a/compiler/rustc_index/src/interval.rs
+++ b/compiler/rustc_index/src/interval.rs
@@ -135,10 +135,7 @@ impl<I: Idx> IntervalSet<I> {
         };
         debug_assert!(
             self.check_invariants(),
-            "wrong intervals after insert {:?}..={:?} to {:?}",
-            start,
-            end,
-            self
+            "wrong intervals after insert {start:?}..={end:?} to {self:?}"
         );
         result
     }
diff --git a/compiler/rustc_index/src/vec.rs b/compiler/rustc_index/src/vec.rs
index 39aa27a23..68cdc6d77 100644
--- a/compiler/rustc_index/src/vec.rs
+++ b/compiler/rustc_index/src/vec.rs
@@ -4,7 +4,6 @@ use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 use std::fmt;
 use std::fmt::Debug;
 use std::hash::Hash;
-use std::iter::FromIterator;
 use std::marker::PhantomData;
 use std::ops::{Index, IndexMut, RangeBounds};
 use std::slice;
@@ -208,7 +207,12 @@ impl<I: Idx, T> IndexVec<I, T> {
         &'a mut self,
         range: R,
     ) -> impl Iterator<Item = (I, T)> + 'a {
-        self.raw.drain(range).enumerate().map(|(n, t)| (I::new(n), t))
+        let begin = match range.start_bound() {
+            std::ops::Bound::Included(i) => *i,
+            std::ops::Bound::Excluded(i) => i.checked_add(1).unwrap(),
+            std::ops::Bound::Unbounded => 0,
+        };
+        self.raw.drain(range).enumerate().map(move |(n, t)| (I::new(begin + n), t))
     }
 
     #[inline]
diff --git a/compiler/rustc_index/src/vec/tests.rs b/compiler/rustc_index/src/vec/tests.rs
index 915d2e8bc..cb0f0db22 100644
--- a/compiler/rustc_index/src/vec/tests.rs
+++ b/compiler/rustc_index/src/vec/tests.rs
@@ -3,7 +3,10 @@
 // Allows the macro invocation below to work
 use crate as rustc_index;
 
-rustc_macros::newtype_index!(struct MyIdx { MAX = 0xFFFF_FFFA });
+rustc_macros::newtype_index! {
+    #[max = 0xFFFF_FFFA]
+    struct MyIdx {}
+}
 
 #[test]
 fn index_size_is_optimized() {