Re: [PATCH v2 4/8] linux-user/mips/cpu_loop: silence the compiler warnings

[Laurent Vivier]

Le 30/10/2020 à 01:40, Chen Qun a écrit :
> When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
> linux-user/mips/cpu_loop.c: In function ‘cpu_loop’:
> linux-user/mips/cpu_loop.c:104:24: warning: this statement may fall through 
> [-Wimplicit-fallthrough=]
>   104 |                     if ((ret = get_user_ual(arg8, sp_reg + 28)) != 0) 
> {
>       |                        ^
> linux-user/mips/cpu_loop.c:107:17: note: here
>   107 |                 case 7:
>       |                 ^~~~
> linux-user/mips/cpu_loop.c:108:24: warning: this statement may fall through 
> [-Wimplicit-fallthrough=]
>   108 |                     if ((ret = get_user_ual(arg7, sp_reg + 24)) != 0) 
> {
>       |                        ^
> linux-user/mips/cpu_loop.c:111:17: note: here
>   111 |                 case 6:
>       |                 ^~~~
> linux-user/mips/cpu_loop.c:112:24: warning: this statement may fall through 
> [-Wimplicit-fallthrough=]
>   112 |                     if ((ret = get_user_ual(arg6, sp_reg + 20)) != 0) 
> {
>       |                        ^
> linux-user/mips/cpu_loop.c:115:17: note: here
>   115 |                 case 5:
>       |                 ^~~~
> 
> 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>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> ---
> Cc: Laurent Vivier <laurent@vivier.eu>
> ---
>  linux-user/mips/cpu_loop.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/linux-user/mips/cpu_loop.c b/linux-user/mips/cpu_loop.c
> index 553e8ca7f5..cfe7ba5c47 100644
> --- a/linux-user/mips/cpu_loop.c
> +++ b/linux-user/mips/cpu_loop.c
> @@ -104,18 +104,22 @@ void cpu_loop(CPUMIPSState *env)
>                      if ((ret = get_user_ual(arg8, sp_reg + 28)) != 0) {
>                          goto done_syscall;
>                      }
> +                    /* fall through */
>                  case 7:
>                      if ((ret = get_user_ual(arg7, sp_reg + 24)) != 0) {
>                          goto done_syscall;
>                      }
> +                    /* fall through */
>                  case 6:
>                      if ((ret = get_user_ual(arg6, sp_reg + 20)) != 0) {
>                          goto done_syscall;
>                      }
> +                    /* fall through */
>                  case 5:
>                      if ((ret = get_user_ual(arg5, sp_reg + 16)) != 0) {
>                          goto done_syscall;
>                      }
> +                    /* fall through */
>                  default:
>                      break;
>                  }
> 

Applied to my linux-user-for-5.2 branch.

Thanks,
Laurent