diff --git a/src/umqtt.c b/src/umqtt.c
index 238fdb4..a61a7c3 100644
--- a/src/umqtt.c
+++ b/src/umqtt.c
@@ -1393,7 +1393,7 @@ int umqtt_start(struct umqtt_client *client)
             set_uplink_recon_tick(client, UPLINK_LAST_TICK);
 
             rt_memset(&msg_ack, 0, sizeof(msg_ack));
-            if (RT_EOK == rt_mq_recv(client->msg_queue,
+            if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                     &msg_ack, sizeof(struct umqtt_msg_ack),
                                     rt_tick_from_millisecond(client->mqtt_info.send_timeout * 1000)))
             {
@@ -1512,7 +1512,7 @@ int umqtt_publish(struct umqtt_client *client, enum umqtt_qos qos, const char *t
     _ret = UMQTT_OK;
     if (qos == UMQTT_QOS1)
     {
-        if (RT_EOK == rt_mq_recv(client->msg_queue,
+        if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                 &msg_ack, sizeof(struct umqtt_msg_ack),
                                 rt_tick_from_millisecond(timeout)))
         {
@@ -1547,7 +1547,7 @@ int umqtt_publish(struct umqtt_client *client, enum umqtt_qos qos, const char *t
     }
     else if (qos == UMQTT_QOS2)
     {
-        if (RT_EOK == rt_mq_recv(client->msg_queue,
+        if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                 &msg_ack, sizeof(struct umqtt_msg_ack),
                                 rt_tick_from_millisecond(timeout)))
         {
@@ -1603,7 +1603,7 @@ int umqtt_publish(struct umqtt_client *client, enum umqtt_qos qos, const char *t
         }
         _ret = UMQTT_OK;
 
-        if (RT_EOK == rt_mq_recv(client->msg_queue,
+        if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                 &msg_ack, sizeof(struct umqtt_msg_ack),
                                 rt_tick_from_millisecond(timeout)))
         {
@@ -1718,7 +1718,7 @@ int umqtt_subscribe(struct umqtt_client *client, const char *topic, enum umqtt_q
         set_uplink_recon_tick(client, UPLINK_LAST_TICK);
 
         rt_memset(&msg_ack, 0, sizeof(msg_ack));
-        if (RT_EOK == rt_mq_recv(client->msg_queue,
+        if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                 &msg_ack, sizeof(struct umqtt_msg_ack),
                                 rt_tick_from_millisecond(client->mqtt_info.send_timeout * 1000)))
         {
@@ -1817,7 +1817,7 @@ int umqtt_unsubscribe(struct umqtt_client *client, const char *topic)
                 set_uplink_recon_tick(client, UPLINK_LAST_TICK);
 
                 rt_memset(&msg_ack, 0, sizeof(msg_ack));
-                if (RT_EOK == rt_mq_recv(client->msg_queue,
+                if (sizeof(struct umqtt_msg_ack) == rt_mq_recv(client->msg_queue,
                                         &msg_ack, sizeof(struct umqtt_msg_ack),
                                         rt_tick_from_millisecond(client->mqtt_info.send_timeout * 1000)))
                 {