Do not run the code when results are not used

serde-rs · Jul 23, 2023 · f709fc0 · f709fc0
1 parent 089aae1
commit f709fc0
Showing 1 changed file with 15 additions and 15 deletions.
diff --git a/serde_derive/src/de.rs b/serde_derive/src/de.rs
@@ -2281,21 +2281,6 @@ fn deserialize_identifier(
         &fallthrough_arm_tokens
     };
 
-    let u64_fallthrough_arm_tokens;
-    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(
-                _serde::de::Unexpected::Unsigned(__value),
-                &#fallthrough_msg,
-            ))
-        };
-        &u64_fallthrough_arm_tokens
-    };
-
     let visit_other = if collect_other_fields {
         quote! {
             fn visit_bool<__E>(self, __value: bool) -> _serde::__private::Result<Self::Value, __E>
@@ -2395,6 +2380,21 @@ fn deserialize_identifier(
             quote!(#i => _serde::__private::Ok(#this_value::#ident))
         });
 
+        let u64_fallthrough_arm_tokens;
+        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(
+                    _serde::de::Unexpected::Unsigned(__value),
+                    &#fallthrough_msg,
+                ))
+            };
+            &u64_fallthrough_arm_tokens
+        };
+
         quote! {
             fn visit_u64<__E>(self, __value: u64) -> _serde::__private::Result<Self::Value, __E>
             where