diff --git a/src/streams/serial/iostream_serial.c b/src/streams/serial/iostream_serial.c
index c9ed7f7555..2d288a4181 100644
--- a/src/streams/serial/iostream_serial.c
+++ b/src/streams/serial/iostream_serial.c
@@ -138,7 +138,7 @@ static tk_ostream_t* tk_iostream_serial_get_ostream(tk_iostream_t* stream) {
 
 tk_iostream_t* tk_iostream_serial_create(const char* port) {
   tk_object_t* obj = NULL;
-  serial_handle_t fd = NULL;
+  serial_handle_t fd = (serial_handle_t)NULL;
   tk_iostream_serial_t* iostream_serial = NULL;
   return_value_if_fail(port != NULL, NULL);
 
diff --git a/tests/conf_json_test.cc b/tests/conf_json_test.cc
index 227a2f4014..26da3678c9 100644
--- a/tests/conf_json_test.cc
+++ b/tests/conf_json_test.cc
@@ -779,6 +779,7 @@ TEST(ConfJson, comment) {
 const char* data = "\
 {\
     \"log_message\": {\
+        \"a\":1,\"b\":2,\
         \"enable\": true, /*是否启用告警信息*/\
         \"fields_count\": 4, /*告警信息中带的字段个数: 级别 | 时间 | 设备 | 信息*/\
         \"fields_seperator\": \"|\", /*字段之间的分隔符*/\
@@ -786,6 +787,8 @@ const char* data = "\
     }\
 }";
   conf_doc_t* doc = conf_doc_load_json(data, -1);
+  ASSERT_EQ(conf_doc_get_int(doc, "log_message.a", 0), 1);
+  ASSERT_EQ(conf_doc_get_int(doc, "log_message.b", 0), 2);
   ASSERT_EQ(conf_doc_get_int(doc, "log_message.fields_count", 0), 4);
   ASSERT_EQ(conf_doc_get_int(doc, "log_message.max_rows", 0), 1000);