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[PATCH 04/12] hw/timer/renesas_tmr: silence the compiler warnings

Thomas Huth posted 12 patches 5 years, 1 month ago
Maintainers: Aurelien Jarno <aurelien@aurel32.net>, "Alex Bennée" <alex.bennee@linaro.org>, Peter Maydell <peter.maydell@linaro.org>, Richard Henderson <richard.henderson@linaro.org>, Guan Xuetao <gxt@mprc.pku.edu.cn>, Andrzej Zaborowski <balrogg@gmail.com>
There is a newer version of this series
[PATCH 04/12] hw/timer/renesas_tmr: silence the compiler warnings
Posted by Thomas Huth 5 years, 1 month ago 
From: Chen Qun <kuhn.chenqun@huawei.com>

When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
../hw/timer/renesas_tmr.c: In function ‘tmr_read’:
../hw/timer/renesas_tmr.c:221:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
  221 |         } else if (ch == 0) {i
      |                   ^
../hw/timer/renesas_tmr.c:224:5: note: here
  224 |     case A_TCORB:
      |     ^~~~

Add the corresponding "fall through" comment to fix it.

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Message-Id: <20201028041819.2169003-10-kuhn.chenqun@huawei.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 hw/timer/renesas_tmr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/timer/renesas_tmr.c b/hw/timer/renesas_tmr.c
index 446f2eacdd..e03a8155b2 100644
--- a/hw/timer/renesas_tmr.c
+++ b/hw/timer/renesas_tmr.c
@@ -221,6 +221,7 @@ static uint64_t tmr_read(void *opaque, hwaddr addr, unsigned size)
         } else if (ch == 0) {
             return concat_reg(tmr->tcora);
         }
+        /* fall through */
     case A_TCORB:
         if (size == 1) {
             return tmr->tcorb[ch];
-- 
2.27.0
Re: [PATCH 04/12] hw/timer/renesas_tmr: silence the compiler warnings
Posted by Peter Maydell 5 years, 1 month ago 
On Fri, 11 Dec 2020 at 15:24, Thomas Huth <thuth@redhat.com> wrote:
>
> From: Chen Qun <kuhn.chenqun@huawei.com>
>
> When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
> ../hw/timer/renesas_tmr.c: In function ‘tmr_read’:
> ../hw/timer/renesas_tmr.c:221:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
>   221 |         } else if (ch == 0) {i
>       |                   ^
> ../hw/timer/renesas_tmr.c:224:5: note: here
>   224 |     case A_TCORB:
>       |     ^~~~
>
> Add the corresponding "fall through" comment to fix it.
>
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
> Message-Id: <20201028041819.2169003-10-kuhn.chenqun@huawei.com>
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  hw/timer/renesas_tmr.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/hw/timer/renesas_tmr.c b/hw/timer/renesas_tmr.c
> index 446f2eacdd..e03a8155b2 100644
> --- a/hw/timer/renesas_tmr.c
> +++ b/hw/timer/renesas_tmr.c
> @@ -221,6 +221,7 @@ static uint64_t tmr_read(void *opaque, hwaddr addr, unsigned size)
>          } else if (ch == 0) {
>              return concat_reg(tmr->tcora);
>          }
> +        /* fall through */
>      case A_TCORB:
>          if (size == 1) {
>              return tmr->tcorb[ch];

Yes, but maybe we should just get the patch that
refactors this code in instead ?

thanks
-- PMM
Re: [PATCH 04/12] hw/timer/renesas_tmr: silence the compiler warnings
Posted by Thomas Huth 5 years, 1 month ago 
On 11/12/2020 16.38, Peter Maydell wrote:
> On Fri, 11 Dec 2020 at 15:24, Thomas Huth <thuth@redhat.com> wrote:
>>
>> From: Chen Qun <kuhn.chenqun@huawei.com>
>>
>> When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
>> ../hw/timer/renesas_tmr.c: In function ‘tmr_read’:
>> ../hw/timer/renesas_tmr.c:221:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
>>   221 |         } else if (ch == 0) {i
>>       |                   ^
>> ../hw/timer/renesas_tmr.c:224:5: note: here
>>   224 |     case A_TCORB:
>>       |     ^~~~
>>
>> Add the corresponding "fall through" comment to fix it.
>>
>> Reported-by: Euler Robot <euler.robot@huawei.com>
>> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
>> Message-Id: <20201028041819.2169003-10-kuhn.chenqun@huawei.com>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>>  hw/timer/renesas_tmr.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/hw/timer/renesas_tmr.c b/hw/timer/renesas_tmr.c
>> index 446f2eacdd..e03a8155b2 100644
>> --- a/hw/timer/renesas_tmr.c
>> +++ b/hw/timer/renesas_tmr.c
>> @@ -221,6 +221,7 @@ static uint64_t tmr_read(void *opaque, hwaddr addr, unsigned size)
>>          } else if (ch == 0) {
>>              return concat_reg(tmr->tcora);
>>          }
>> +        /* fall through */
>>      case A_TCORB:
>>          if (size == 1) {
>>              return tmr->tcorb[ch];
> 
> Yes, but maybe we should just get the patch that
> refactors this code in instead ?

I think that patch had a bug in it:

 https://lore.kernel.org/qemu-devel/28b04149-bbd9-12ed-0e40-3c3da9fee672@redhat.com/

So I was hoping that Yoshinori Sato would send a new version or at least a
reply with a clarification, but I've never seen a response... so for the
time being, I'd suggest to go with Chen Qun's patch instead, which certainly
does not hurt.

 Thomas

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