1 files changed, 3 insertions, 4 deletions
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index f933b9b161c..31596a1e9bf 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -2554,10 +2554,9 @@ pub enum AttrStyle {
 }
 
 rustc_index::newtype_index! {
-    pub struct AttrId {
-        ENCODABLE = custom
-        DEBUG_FORMAT = "AttrId({})"
-    }
+    #[custom_encodable]
+    #[debug_format = "AttrId({})]"]
+    pub struct AttrId {}
 }
 
 impl<S: Encoder> Encodable<S> for AttrId {