Re: [PATCH 4.19 3/6] mwifiex: Remove unnecessary braces from HostCmd_SET_SEQ_NO_BSS_INFO

From: Greg KH
Date: Mon Dec 20 2021 - 05:56:44 EST


On Fri, Dec 17, 2021 at 03:41:16PM +0100, Anders Roxell wrote:
> From: Nathan Chancellor <natechancellor@xxxxxxxxx>
>
> commit 6a953dc4dbd1c7057fb765a24f37a5e953c85fb0 upstream.
>
> A new warning in clang points out when macro expansion might result in a
> GNU C statement expression. There is an instance of this in the mwifiex
> driver:
>
> drivers/net/wireless/marvell/mwifiex/cmdevt.c:217:34: warning: '}' and
> ')' tokens terminating statement expression appear in different macro
> expansion contexts [-Wcompound-token-split-by-macro]
> host_cmd->seq_num = cpu_to_le16(HostCmd_SET_SEQ_NO_BSS_INFO
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/marvell/mwifiex/fw.h:519:46: note: expanded from
> macro 'HostCmd_SET_SEQ_NO_BSS_INFO'
> (((type) & 0x000f) << 12); }
> ^
>
> This does not appear to be a real issue. Removing the braces and
> replacing them with parentheses will fix the warning and not change the
> meaning of the code.
>
> Fixes: 5e6e3a92b9a4 ("wireless: mwifiex: initial commit for Marvell mwifiex driver")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1146
> Reported-by: Andy Lavr <andy.lavr@xxxxxxxxx>
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
> Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
> ---
> drivers/net/wireless/marvell/mwifiex/cmdevt.c | 4 ++--
> drivers/net/wireless/marvell/mwifiex/fw.h | 8 ++++----
> 2 files changed, 6 insertions(+), 6 deletions(-)

Also needed in 5.4.y, right?