Re: [PATCH] isdn: hfc_{pci,sx}: Avoid empty body if statements and use proper register accessors

[Masahiro Yamada]

Hi Nathan,

On Thu, Oct 18, 2018 at 3:09 AM Nathan Chancellor
<natechancellor@xxxxxxxxx> wrote:
>
> Clang warns:
>
> drivers/isdn/hisax/hfc_pci.c:131:34: error: if statement has empty body
> [-Werror,-Wempty-body]
>         if (Read_hfc(cs, HFCPCI_INT_S1));
>                                         ^
> drivers/isdn/hisax/hfc_pci.c:131:34: note: put the semicolon on a
> separate line to silence this warning
>
> Use the format found in drivers/isdn/hardware/mISDN/hfcpci.c of casting
> the return of Read_hfc to void, instead of using an empty if statement.
>
> While we're at it, Masahiro Yamada pointed out that {Read,Write}_hfc
> should be using a standard access method in hfc_pci.h. Use the one found
> in drivers/isdn/hardware/mISDN/hfc_pci.h.
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/66
> Suggested-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
>  drivers/isdn/hisax/hfc_pci.c | 6 +++---
>  drivers/isdn/hisax/hfc_pci.h | 4 ++--
>  drivers/isdn/hisax/hfc_sx.c  | 6 +++---
>  3 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/isdn/hisax/hfc_pci.c b/drivers/isdn/hisax/hfc_pci.c
> index 8e5b03161b2f..a63b9155b697 100644
> --- a/drivers/isdn/hisax/hfc_pci.c
> +++ b/drivers/isdn/hisax/hfc_pci.c
> @@ -128,7 +128,7 @@ reset_hfcpci(struct IsdnCardState *cs)
>         Write_hfc(cs, HFCPCI_INT_M1, cs->hw.hfcpci.int_m1);
>
>         /* Clear already pending ints */
> -       if (Read_hfc(cs, HFCPCI_INT_S1));
> +       (void) Read_hfc(cs, HFCPCI_INT_S1);



Why is this '(void)' necessary?

I see no warning without it.



-- 
Best Regards
Masahiro Yamada