diff --git a/samples/dev_model/dev_model_sample.c b/samples/dev_model/dev_model_sample.c
index 3985733..e164904 100644
--- a/samples/dev_model/dev_model_sample.c
+++ b/samples/dev_model/dev_model_sample.c
@@ -108,6 +108,7 @@ static int _setup_connect_init_params(MQTTInitParams* initParams)
 static void mqtt_devmodel_thread(void)
 {
     int rc;
+    int i = 0;
 
     MQTTInitParams init_params = DEFAULT_MQTT_INIT_PARAMS;
     rc = _setup_connect_init_params(&init_params);
@@ -138,7 +139,7 @@ static void mqtt_devmodel_thread(void)
     IOT_DM_RegisterCallback(PROPERTY_SET , h_dm, property_set_cb);
     IOT_DM_Yield(h_dm, 200);
 
-    for (int i = 0; i < 10; i++) {
+    for (i = 0; i < 10; i++) {
         IOT_DM_Property_Report(h_dm, PROPERTY_POST, i * 2, "{\"volume\": {\"Value\":50}}");
         IOT_DM_TriggerEvent(h_dm, i * 2 + 1, "low_power_alert", "{\"power\": 5}");
 
diff --git a/uiot/mqtt/src/mqtt_client_common.c b/uiot/mqtt/src/mqtt_client_common.c
index 6992c42..18f63af 100644
--- a/uiot/mqtt/src/mqtt_client_common.c
+++ b/uiot/mqtt/src/mqtt_client_common.c
@@ -920,7 +920,8 @@ static int _handle_suback_packet(UIoT_Client *pClient, Timer *timer, QoS qos)
 
     int flag_dup = 0, i_free = -1;
 
-    for (int j = 0; j <  count; j++) {
+    int j;
+    for (j = 0; j <  count; j++) {
         /* In negative case, grantedQoS will be 0xFFFF FF80, which means -128 */
         if ((uint8_t)grantedQoS[j] == 0x80) {
             sub_nack = true;