diff --git a/libs/hbb_common/src/socket_client.rs b/libs/hbb_common/src/socket_client.rs
index dde237267..6f62163d1 100644
--- a/libs/hbb_common/src/socket_client.rs
+++ b/libs/hbb_common/src/socket_client.rs
@@ -56,7 +56,7 @@ pub fn test_if_valid_server(host: &str) -> String {
     match Config::get_network_type() {
         NetworkType::Direct => match host.to_socket_addrs() {
             Err(err) => err.to_string(),
-            Ok(x) => "".to_owned(),
+            Ok(_) => "".to_owned(),
         },
         NetworkType::ProxySocks => match &host.into_target_addr() {
             Err(err) => err.to_string(),