On 17/12/2019 18.55, Thomas Huth wrote:
> On 17/12/2019 18.34, Philippe Mathieu-Daudé wrote:
>> GCC9 is confused by this comment when building with CFLAG
>> -Wimplicit-fallthrough=2:
>>
>> hw/net/imx_fec.c: In function ‘imx_eth_write’:
>> hw/net/imx_fec.c:906:12: error: this statement may fall through
>> [-Werror=implicit-fallthrough=]
>> 906 | if (unlikely(single_tx_ring)) {
>> | ^
>> hw/net/imx_fec.c:912:5: note: here
>> 912 | case ENET_TDAR: /* FALLTHROUGH */
>> | ^~~~
>> cc1: all warnings being treated as errors
>>
>> Rewrite the comments in the correct place, using 'fall through'
>> which is recognized by GCC and static analyzers.
>>
>> Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
>> ---
>> Cc: Peter Chubb <[email protected]>
>> Cc: Peter Maydell <[email protected]>
>> Cc: Jason Wang <[email protected]>
>> Cc: [email protected]
>> ---
>> hw/net/imx_fec.c | 8 +++++---
>> 1 file changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c
>> index bd99236864..30cc07753d 100644
>> --- a/hw/net/imx_fec.c
>> +++ b/hw/net/imx_fec.c
>> @@ -901,15 +901,17 @@ static void imx_eth_write(void *opaque, hwaddr offset,
>> uint64_t value,
>> s->regs[index] = 0;
>> }
>> break;
>> - case ENET_TDAR1: /* FALLTHROUGH */
>> - case ENET_TDAR2: /* FALLTHROUGH */
>> + /* fall through */
>
> Wrong location. And I think you don't need any comment here at all, GCC
> should stay silent without it?
>
>> + case ENET_TDAR1:
>> + case ENET_TDAR2:
>> if (unlikely(single_tx_ring)) {
>> qemu_log_mask(LOG_GUEST_ERROR,
>> "[%s]%s: trying to access TDAR2 or TDAR1\n",
>> TYPE_IMX_FEC, __func__);
>> return;
>> }
>> - case ENET_TDAR: /* FALLTHROUGH */
>> + /* fall through */
>
> I'd suggest to simply remove it, too.
/me needsmorecoffee
... of course this hunk was fine. Good that you kept it in v2.
Thomas
>> + case ENET_TDAR:
>> if (s->regs[ENET_ECR] & ENET_ECR_ETHEREN) {
>> s->regs[index] = ENET_TDAR_TDAR;
>> imx_eth_do_tx(s, index);
>>
>
> Thomas
>
