diff --git a/src/expr.rs b/src/expr.rs
index a417508b5..a267a2e68 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -223,12 +223,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match expr {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         Expr::Array(expr) => {...}
         //         Expr::Assign(expr) => {...}
         //         ...
         //         Expr::Yield(expr) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
diff --git a/src/item.rs b/src/item.rs
index b56f8b239..4e404e266 100644
--- a/src/item.rs
+++ b/src/item.rs
@@ -70,12 +70,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match item {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         Item::Const(item) => {...}
         //         Item::Enum(item) => {...}
         //         ...
         //         Item::Verbatim(item) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
@@ -510,12 +511,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match item {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         ForeignItem::Fn(item) => {...}
         //         ForeignItem::Static(item) => {...}
         //         ...
         //         ForeignItem::Verbatim(item) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
@@ -604,12 +606,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match item {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         TraitItem::Const(item) => {...}
         //         TraitItem::Fn(item) => {...}
         //         ...
         //         TraitItem::Verbatim(item) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
@@ -700,12 +703,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match item {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         ImplItem::Const(item) => {...}
         //         ImplItem::Fn(item) => {...}
         //         ...
         //         ImplItem::Verbatim(item) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
diff --git a/src/pat.rs b/src/pat.rs
index c835d772f..ce6399d9f 100644
--- a/src/pat.rs
+++ b/src/pat.rs
@@ -74,12 +74,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match pat {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         Pat::Box(pat) => {...}
         //         Pat::Ident(pat) => {...}
         //         ...
         //         Pat::Wild(pat) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //
diff --git a/src/ty.rs b/src/ty.rs
index a5049f080..3213e7f3b 100644
--- a/src/ty.rs
+++ b/src/ty.rs
@@ -64,12 +64,13 @@ ast_enum_of_structs! {
         // For testing exhaustiveness in downstream code, use the following idiom:
         //
         //     match ty {
+        //         #![cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
+        //
         //         Type::Array(ty) => {...}
         //         Type::BareFn(ty) => {...}
         //         ...
         //         Type::Verbatim(ty) => {...}
         //
-        //         #[cfg_attr(test, deny(non_exhaustive_omitted_patterns))]
         //         _ => { /* some sane fallback */ }
         //     }
         //