GD32VF103出现to free a bad data block:错误

static void led(void *pt)
{
    longan_led_init();
    while(1){
        /* turn on builtin led */
        longan_led_on();
        rt_thread_delay(1000);
        /* turn off uiltin led */
        longan_led_off();
        rt_thread_delay(1000);
    }
}
/*!
    \brief      main function
    \param[in]  none
    \param[out] none
    \retval     none
*/
int main(void)
{
    rt_thread_t tid;
    tid = rt_thread_create("led",led,RT_NULL,1024,6,20);
    RT_ASSERT(tid != RT_NULL);
    /* startup */
    rt_thread_startup(tid);
}

startup a thread:led with priority:6
thread resume:  led
thread suspend:  led
to free a bad data block:
mem: 0x200001c0, used flag: 2048, magic code: 0x0fb0
(mem->magic == HEAP_MAGIC) assertion failed at function:rt_free, line number:575