error: a label can only be part of a statement and a declaration is not a statement

来源：互联网发布：购买域名后如何使用编辑：程序博客网时间：2024/05/21 07:07

在开发代码中使用switch出现的一个编译错误：

代码片段如下所示：

    switch(cmd)    {        case EDMA3_DRV_IOCTL_DMA_BUFFER_ALLOC:            dma_buf_info_t *dma_buf_info = (dma_buf_info_t *)arg;                        if(NULL == dma_buf_info                || NULL == dma_buf_info->buf_info)            {                RPT(RPT_ERR, "null pointer,err");                return -1;            }            for(i=0; i<dma_buf_info->num_buffers; i++)            {                dma_buf_info->buf_info[i].virtAddr_kernel_space = (uint8_t *)dma_alloc_coherent(NULL,                                                          dma_buf_info->buffer_size,                                                          (dma_addr_t *)&dma_buf_info->buf_info[i].phyAddr,                                                          GFP_KERNEL);                if(0 == dma_buf_info->buf_info[i].phyAddr)                {                    RPT(RPT_ERR, "alloc dma buffer,error!!  phyAddr == 0");                    return -1;                }                RPT(RPT_DBG,                "Allocated DMA phy memory: Phy Address: 0x%llx Virtual Address :0x%p Size :0x%x successfull!!",                                                            dma_buf_info->buf_info[i].phyAddr,                                                            dma_buf_info->buf_info[i].virtAddr_kernel_space,                                                            (unsigned int)dma_buf_info->buffer_size);            }             break;

修改方法，在case 后加大括号将代码括起来，如下所示

    switch(cmd)    {        case EDMA3_DRV_IOCTL_DMA_BUFFER_ALLOC:        {            dma_buf_info_t *dma_buf_info = (dma_buf_info_t *)arg;                        if(NULL == dma_buf_info                || NULL == dma_buf_info->buf_info)            {                RPT(RPT_ERR, "null pointer,err");                return -1;            }            for(i=0; i<dma_buf_info->num_buffers; i++)            {                dma_buf_info->buf_info[i].virtAddr_kernel_space = (uint8_t *)dma_alloc_coherent(NULL,                                                          dma_buf_info->buffer_size,                                                          (dma_addr_t *)&dma_buf_info->buf_info[i].phyAddr,                                                          GFP_KERNEL);                if(0 == dma_buf_info->buf_info[i].phyAddr)                {                    RPT(RPT_ERR, "alloc dma buffer,error!!  phyAddr == 0");                    return -1;                }                RPT(RPT_DBG,                "Allocated DMA phy memory: Phy Address: 0x%llx Virtual Address :0x%p Size :0x%x successfull!!",                                                            dma_buf_info->buf_info[i].phyAddr,                                                            dma_buf_info->buf_info[i].virtAddr_kernel_space,                                                            (unsigned int)dma_buf_info->buffer_size);            }        }               break;

解决

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