Unexpected warning

Question

I am receiving an unexpected warning from nrf_atfifo_item_get that reports "Get failed - no item in the FIFO." This occurs when I start advertising using 
 void advertising_start(bool erase_bonds) 
 This calls bsp_led_indication which calls app_timer_start which triggers drv_rtc_irq_trigger 
 I am assuming this is to catch short timer periods, but can this warning be avoided so that there is no call to the rtc trigger?

Malcolm · Answer

The following is a workaround that resets the head of the FIFO queue to its original value after the check so that it correctly returns the next item and avoids the call that would return an empty queue message. 
 /** * @brief Function for processing user requests. * * Function is called only in the context of RTC interrupt. */ static void timer_req_process(drv_rtc_t const * const p_instance) { nrf_atfifo_item_get_t fifo_ctx; timer_req_t * p_req; bool req = nrf_atfifo_item_check(m_req_fifo, &fifo_ctx); while (req) { m_req_fifo->head.tag = fifo_ctx.last_head.tag; m_req_fifo->head.pos.wr = fifo_ctx.last_head.pos.wr; m_req_fifo->head.pos.rd = fifo_ctx.last_head.pos.rd; p_req = nrf_atfifo_item_get(m_req_fifo, &fifo_ctx); switch (p_req->type) {