diff --git a/src/ipc.c b/src/ipc.c
index a467c14151..da2996a30e 100755
--- a/src/ipc.c
+++ b/src/ipc.c
@@ -287,6 +287,7 @@ rt_err_t rt_sem_init(rt_sem_t    sem,
 {
     RT_ASSERT(sem != RT_NULL);
     RT_ASSERT(value < 0x10000U);
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
 
     /* initialize object */
     rt_object_init(&(sem->parent.parent), RT_Object_Class_Semaphore, name);
@@ -377,8 +378,10 @@ rt_sem_t rt_sem_create(const char *name, rt_uint32_t value, rt_uint8_t flag)
 {
     rt_sem_t sem;
 
-    RT_DEBUG_NOT_IN_INTERRUPT;
     RT_ASSERT(value < 0x10000U);
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
+
+    RT_DEBUG_NOT_IN_INTERRUPT;
 
     /* allocate object */
     sem = (rt_sem_t)rt_object_allocate(RT_Object_Class_Semaphore, name);
@@ -419,13 +422,13 @@ RTM_EXPORT(rt_sem_create);
  */
 rt_err_t rt_sem_delete(rt_sem_t sem)
 {
-    RT_DEBUG_NOT_IN_INTERRUPT;
-
     /* parameter check */
     RT_ASSERT(sem != RT_NULL);
     RT_ASSERT(rt_object_get_type(&sem->parent.parent) == RT_Object_Class_Semaphore);
     RT_ASSERT(rt_object_is_systemobject(&sem->parent.parent) == RT_FALSE);
 
+    RT_DEBUG_NOT_IN_INTERRUPT;
+
     /* wakeup all suspended threads */
     _ipc_list_resume_all(&(sem->parent.suspend_thread));
 
@@ -848,13 +851,13 @@ RTM_EXPORT(rt_mutex_create);
  */
 rt_err_t rt_mutex_delete(rt_mutex_t mutex)
 {
-    RT_DEBUG_NOT_IN_INTERRUPT;
-
     /* parameter check */
     RT_ASSERT(mutex != RT_NULL);
     RT_ASSERT(rt_object_get_type(&mutex->parent.parent) == RT_Object_Class_Mutex);
     RT_ASSERT(rt_object_is_systemobject(&mutex->parent.parent) == RT_FALSE);
 
+    RT_DEBUG_NOT_IN_INTERRUPT;
+
     /* wakeup all suspended threads */
     _ipc_list_resume_all(&(mutex->parent.suspend_thread));
 
@@ -1257,6 +1260,7 @@ rt_err_t rt_event_init(rt_event_t event, const char *name, rt_uint8_t flag)
 {
     /* parameter check */
     RT_ASSERT(event != RT_NULL);
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
 
     /* initialize object */
     rt_object_init(&(event->parent.parent), RT_Object_Class_Event, name);
@@ -1343,6 +1347,8 @@ rt_event_t rt_event_create(const char *name, rt_uint8_t flag)
 {
     rt_event_t event;
 
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
+
     RT_DEBUG_NOT_IN_INTERRUPT;
 
     /* allocate object */
@@ -1766,6 +1772,7 @@ rt_err_t rt_mb_init(rt_mailbox_t mb,
                     rt_uint8_t   flag)
 {
     RT_ASSERT(mb != RT_NULL);
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
 
     /* initialize object */
     rt_object_init(&(mb->parent.parent), RT_Object_Class_MailBox, name);
@@ -1864,6 +1871,8 @@ rt_mailbox_t rt_mb_create(const char *name, rt_size_t size, rt_uint8_t flag)
 {
     rt_mailbox_t mb;
 
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
+
     RT_DEBUG_NOT_IN_INTERRUPT;
 
     /* allocate object */
@@ -1919,13 +1928,13 @@ RTM_EXPORT(rt_mb_create);
  */
 rt_err_t rt_mb_delete(rt_mailbox_t mb)
 {
-    RT_DEBUG_NOT_IN_INTERRUPT;
-
     /* parameter check */
     RT_ASSERT(mb != RT_NULL);
     RT_ASSERT(rt_object_get_type(&mb->parent.parent) == RT_Object_Class_MailBox);
     RT_ASSERT(rt_object_is_systemobject(&mb->parent.parent) == RT_FALSE);
 
+    RT_DEBUG_NOT_IN_INTERRUPT;
+
     /* resume all suspended thread */
     _ipc_list_resume_all(&(mb->parent.suspend_thread));
 
@@ -2463,6 +2472,7 @@ rt_err_t rt_mq_init(rt_mq_t     mq,
 
     /* parameter check */
     RT_ASSERT(mq != RT_NULL);
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
 
     /* initialize object */
     rt_object_init(&(mq->parent.parent), RT_Object_Class_MessageQueue, name);
@@ -2584,6 +2594,8 @@ rt_mq_t rt_mq_create(const char *name,
     struct rt_mq_message *head;
     register rt_base_t temp;
 
+    RT_ASSERT((flag == RT_IPC_FLAG_FIFO) || (flag == RT_IPC_FLAG_PRIO));
+
     RT_DEBUG_NOT_IN_INTERRUPT;
 
     /* allocate object */
@@ -2658,13 +2670,13 @@ RTM_EXPORT(rt_mq_create);
  */
 rt_err_t rt_mq_delete(rt_mq_t mq)
 {
-    RT_DEBUG_NOT_IN_INTERRUPT;
-
     /* parameter check */
     RT_ASSERT(mq != RT_NULL);
     RT_ASSERT(rt_object_get_type(&mq->parent.parent) == RT_Object_Class_MessageQueue);
     RT_ASSERT(rt_object_is_systemobject(&mq->parent.parent) == RT_FALSE);
 
+    RT_DEBUG_NOT_IN_INTERRUPT;
+
     /* resume all suspended thread */
     _ipc_list_resume_all(&(mq->parent.suspend_thread));
     /* also resume all message queue private suspended thread */