diff --git a/src/ipc.c b/src/ipc.c index 454fcb5439..4261f617b0 100644 --- a/src/ipc.c +++ b/src/ipc.c @@ -1764,8 +1764,12 @@ rt_err_t rt_mb_recv(rt_mailbox_t mb, rt_ubase_t *value, rt_int32_t timeout) ++ mb->out_offset; if (mb->out_offset >= mb->size) mb->out_offset = 0; + /* decrease message entry */ - mb->entry --; + if(mb->entry > 0) + { + mb->entry --; + } /* resume suspended thread */ if (!rt_list_isempty(&(mb->suspend_sender_thread))) @@ -2439,7 +2443,10 @@ rt_err_t rt_mq_recv(rt_mq_t mq, mq->msg_queue_tail = RT_NULL; /* decrease message entry */ - mq->entry --; + if(mq->entry > 0) + { + mq->entry --; + } /* enable interrupt */ rt_hw_interrupt_enable(temp);