diff --git a/compiler/rustc_index/src/vec.rs b/compiler/rustc_index/src/vec.rs
index e3c6528b21885..cc42cb24fb6b4 100644
--- a/compiler/rustc_index/src/vec.rs
+++ b/compiler/rustc_index/src/vec.rs
@@ -104,7 +104,8 @@ macro_rules! newtype_index {
      @vis          [$v:vis]
      @debug_format [$debug_format:tt]) => (
         $(#[$attrs])*
-        #[derive(Copy, PartialEq, Eq, Hash, PartialOrd, Ord, $($derives),*)]
+        // #[derive(Copy, PartialEq, Eq, Hash, PartialOrd, Ord, $($derives),*)]
+        #[derive(Copy, PartialEq, Eq, Hash, $($derives),*)]
         #[rustc_layout_scalar_valid_range_end($max)]
         $v struct $type {
             private: u32