diff --git a/ast/asdl_rs.py b/ast/asdl_rs.py
index bb98706..24c679d 100755
--- a/ast/asdl_rs.py
+++ b/ast/asdl_rs.py
@@ -425,7 +425,7 @@ class FoldTraitDefVisitor(EmitVisitor):
                 self.map_user(user)
             }
             #[cfg(not(feature = "more-attributes"))]
-            fn map_user_cfg(&mut self, _user: U) -> Result<std::marker::PhantomData<Self::TargetU>, Self::Error> {
+            fn map_user_cfg(&mut self, _user: std::marker::PhantomData<U>) -> Result<std::marker::PhantomData<Self::TargetU>, Self::Error> {
                 Ok(std::marker::PhantomData)
             }
             """,
@@ -496,11 +496,12 @@ class FoldImplVisitor(EmitVisitor):
                 f"{fields_pattern[0]} {{ {fields_pattern[1]}}} {fields_pattern[2]} => {{",
                 depth + 2,
             )
-            if not type_info.has_attributes:
-                self.emit('#[cfg(not(feature = "more-attributes"))]', depth + 3)
-                self.emit("let custom = std::marker::PhantomData;", depth + 3)
-                self.emit('#[cfg(feature = "more-attributes")]', depth + 3)
-            self.emit("let custom = folder.map_user(custom)?;", depth + 3)
+
+            map_user_suffix = "" if type_info.has_attributes else "_cfg"
+            self.emit(
+                f"let custom = folder.map_user{map_user_suffix}(custom)?;", depth + 3
+            )
+
             self.gen_construction(
                 fields_pattern[0], cons.fields, fields_pattern[2], depth + 3
             )
@@ -533,11 +534,8 @@ class FoldImplVisitor(EmitVisitor):
         fields_pattern = self.make_pattern(struct_name, struct_name, product.fields)
         self.emit(f"let {struct_name} {{ {fields_pattern[1]} }} = node;", depth + 1)
 
-        if not has_attributes:
-            self.emit('#[cfg(not(feature = "more-attributes"))]', depth + 3)
-            self.emit("let custom = std::marker::PhantomData;", depth + 3)
-            self.emit('#[cfg(feature = "more-attributes")]', depth + 3)
-        self.emit("let custom = folder.map_user(custom)?;", depth + 3)
+        map_user_suffix = "" if has_attributes else "_cfg"
+        self.emit(f"let custom = folder.map_user{map_user_suffix}(custom)?;", depth + 3)
 
         self.gen_construction(struct_name, product.fields, "", depth + 1)
 
@@ -956,11 +954,7 @@ def write_ast_def(mod, type_info, f):
 
 
 def write_fold_def(mod, type_info, f):
-    f.write(
-        """
-use crate::generic::Custom;
-"""
-    )
+    f.write("use crate::generic::Custom;")
     FoldModuleVisitor(f, type_info).visit(mod)
 
 
diff --git a/ast/src/gen/fold.rs b/ast/src/gen/fold.rs
index 238e749..b9faa6d 100644
--- a/ast/src/gen/fold.rs
+++ b/ast/src/gen/fold.rs
@@ -14,7 +14,7 @@ pub trait Fold<U> {
     #[cfg(not(feature = "more-attributes"))]
     fn map_user_cfg(
         &mut self,
-        _user: U,
+        _user: std::marker::PhantomData<U>,
     ) -> Result<std::marker::PhantomData<Self::TargetU>, Self::Error> {
         Ok(std::marker::PhantomData)
     }
@@ -111,10 +111,7 @@ pub fn fold_mod<U, F: Fold<U> + ?Sized>(
             type_ignores,
             custom,
         }) => {
-            #[cfg(not(feature = "more-attributes"))]
-            let custom = std::marker::PhantomData;
-            #[cfg(feature = "more-attributes")]
-            let custom = folder.map_user(custom)?;
+            let custom = folder.map_user_cfg(custom)?;
             Ok(Mod::Module(ModModule {
                 body: Foldable::fold(body, folder)?,
                 type_ignores: Foldable::fold(type_ignores, folder)?,
@@ -122,20 +119,14 @@ pub fn fold_mod<U, F: Fold<U> + ?Sized>(
             }))
         }
         Mod::Interactive(ModInteractive { body, custom }) => {
-            #[cfg(not(feature = "more-attributes"))]
-            let custom = std::marker::PhantomData;
-            #[cfg(feature = "more-attributes")]
-            let custom = folder.map_user(custom)?;
+            let custom = folder.map_user_cfg(custom)?;
             Ok(Mod::Interactive(ModInteractive {
                 body: Foldable::fold(body, folder)?,
                 custom,
             }))
         }
         Mod::Expression(ModExpression { body, custom }) => {
-            #[cfg(not(feature = "more-attributes"))]
-            let custom = std::marker::PhantomData;
-            #[cfg(feature = "more-attributes")]
-            let custom = folder.map_user(custom)?;
+            let custom = folder.map_user_cfg(custom)?;
             Ok(Mod::Expression(ModExpression {
                 body: Foldable::fold(body, folder)?,
                 custom,
@@ -146,10 +137,7 @@ pub fn fold_mod<U, F: Fold<U> + ?Sized>(
             returns,
             custom,
         }) => {
-            #[cfg(not(feature = "more-attributes"))]
-            let custom = std::marker::PhantomData;
-            #[cfg(feature = "more-attributes")]
-            let custom = folder.map_user(custom)?;
+            let custom = folder.map_user_cfg(custom)?;
             Ok(Mod::FunctionType(ModFunctionType {
                 argtypes: Foldable::fold(argtypes, folder)?,
                 returns: Foldable::fold(returns, folder)?,
@@ -900,10 +888,7 @@ pub fn fold_comprehension<U, F: Fold<U> + ?Sized>(
         is_async,
         custom,
     } = node;
-    #[cfg(not(feature = "more-attributes"))]
-    let custom = std::marker::PhantomData;
-    #[cfg(feature = "more-attributes")]
-    let custom = folder.map_user(custom)?;
+    let custom = folder.map_user_cfg(custom)?;
     Ok(Comprehension {
         target: Foldable::fold(target, folder)?,
         iter: Foldable::fold(iter, folder)?,
@@ -965,10 +950,7 @@ pub fn fold_arguments<U, F: Fold<U> + ?Sized>(
         defaults,
         custom,
     } = node;
-    #[cfg(not(feature = "more-attributes"))]
-    let custom = std::marker::PhantomData;
-    #[cfg(feature = "more-attributes")]
-    let custom = folder.map_user(custom)?;
+    let custom = folder.map_user_cfg(custom)?;
     Ok(Arguments {
         posonlyargs: Foldable::fold(posonlyargs, folder)?,
         args: Foldable::fold(args, folder)?,
@@ -1071,10 +1053,7 @@ pub fn fold_withitem<U, F: Fold<U> + ?Sized>(
         optional_vars,
         custom,
     } = node;
-    #[cfg(not(feature = "more-attributes"))]
-    let custom = std::marker::PhantomData;
-    #[cfg(feature = "more-attributes")]
-    let custom = folder.map_user(custom)?;
+    let custom = folder.map_user_cfg(custom)?;
     Ok(Withitem {
         context_expr: Foldable::fold(context_expr, folder)?,
         optional_vars: Foldable::fold(optional_vars, folder)?,
@@ -1100,10 +1079,7 @@ pub fn fold_match_case<U, F: Fold<U> + ?Sized>(
         body,
         custom,
     } = node;
-    #[cfg(not(feature = "more-attributes"))]
-    let custom = std::marker::PhantomData;
-    #[cfg(feature = "more-attributes")]
-    let custom = folder.map_user(custom)?;
+    let custom = folder.map_user_cfg(custom)?;
     Ok(MatchCase {
         pattern: Foldable::fold(pattern, folder)?,
         guard: Foldable::fold(guard, folder)?,
@@ -1223,10 +1199,7 @@ pub fn fold_type_ignore<U, F: Fold<U> + ?Sized>(
             tag,
             custom,
         }) => {
-            #[cfg(not(feature = "more-attributes"))]
-            let custom = std::marker::PhantomData;
-            #[cfg(feature = "more-attributes")]
-            let custom = folder.map_user(custom)?;
+            let custom = folder.map_user_cfg(custom)?;
             Ok(TypeIgnore::TypeIgnore(TypeIgnoreTypeIgnore {
                 lineno: Foldable::fold(lineno, folder)?,
                 tag: Foldable::fold(tag, folder)?,