diff --git a/serde_derive/src/de.rs b/serde_derive/src/de.rs
index 6474fca0..78f94531 100644
--- a/serde_derive/src/de.rs
+++ b/serde_derive/src/de.rs
@@ -2228,19 +2228,12 @@ fn deserialize_identifier(
         quote!(#(#aliases)|* => _serde::__private::Ok(#this_value::#ident))
     });
 
-    let main_constructors: &Vec<_> = &fields
-        .iter()
-        .map(|(_, ident, _)| quote!(#this_value::#ident))
-        .collect();
-
     let expecting = expecting.unwrap_or(if is_variant {
         "variant identifier"
     } else {
         "field identifier"
     });
 
-    let index_expecting = if is_variant { "variant" } else { "field" };
-
     let bytes_to_str = if fallthrough.is_some() || collect_other_fields {
         None
     } else {
@@ -2292,6 +2285,7 @@ fn deserialize_identifier(
     let u64_fallthrough_arm = if let Some(fallthrough) = &fallthrough {
         fallthrough
     } else {
+        let index_expecting = if is_variant { "variant" } else { "field" };
         let fallthrough_msg = format!("{} index 0 <= i < {}", index_expecting, fields.len());
         u64_fallthrough_arm_tokens = quote! {
             _serde::__private::Err(_serde::de::Error::invalid_value(
@@ -2302,7 +2296,6 @@ fn deserialize_identifier(
         &u64_fallthrough_arm_tokens
     };
 
-    let variant_indices = 0_u64..;
     let visit_other = if collect_other_fields {
         quote! {
             fn visit_bool<__E>(self, __value: bool) -> _serde::__private::Result<Self::Value, __E>
@@ -2397,15 +2390,18 @@ fn deserialize_identifier(
             }
         }
     } else {
+        let u64_mapping = fields.iter().enumerate().map(|(i, (_, ident, _))| {
+            let i = i as u64;
+            quote!(#i => _serde::__private::Ok(#this_value::#ident))
+        });
+
         quote! {
             fn visit_u64<__E>(self, __value: u64) -> _serde::__private::Result<Self::Value, __E>
             where
                 __E: _serde::de::Error,
             {
                 match __value {
-                    #(
-                        #variant_indices => _serde::__private::Ok(#main_constructors),
-                    )*
+                    #(#u64_mapping,)*
                     _ => #u64_fallthrough_arm,
                 }
             }