diff mbox series

mwifiex: Remove unnecessary braces from HostCmd_SET_SEQ_NO_BSS_INFO

Message ID 20200901070834.1015754-1-natechancellor@gmail.com (mailing list archive)
State Accepted
Commit 6a953dc4dbd1c7057fb765a24f37a5e953c85fb0
Delegated to: Kalle Valo
Headers show
Series mwifiex: Remove unnecessary braces from HostCmd_SET_SEQ_NO_BSS_INFO | expand

Commit Message

Nathan Chancellor Sept. 1, 2020, 7:08 a.m. UTC
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@gmail.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 drivers/net/wireless/marvell/mwifiex/cmdevt.c | 4 ++--
 drivers/net/wireless/marvell/mwifiex/fw.h     | 8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

Comments

Nick Desaulniers Sept. 1, 2020, 5:47 p.m. UTC | #1
On Tue, Sep 1, 2020 at 12:08 AM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> 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@gmail.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Wow, that's tricky. The unnecessary extra parens mix with the extra
curly braces to form a GNU C statement expression.  Thanks for the
patch.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

> ---
>  drivers/net/wireless/marvell/mwifiex/cmdevt.c | 4 ++--
>  drivers/net/wireless/marvell/mwifiex/fw.h     | 8 ++++----
>  2 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/wireless/marvell/mwifiex/cmdevt.c b/drivers/net/wireless/marvell/mwifiex/cmdevt.c
> index d068b9075c32..3a11342a6bde 100644
> --- a/drivers/net/wireless/marvell/mwifiex/cmdevt.c
> +++ b/drivers/net/wireless/marvell/mwifiex/cmdevt.c
> @@ -322,9 +322,9 @@ static int mwifiex_dnld_sleep_confirm_cmd(struct mwifiex_adapter *adapter)
>
>         adapter->seq_num++;
>         sleep_cfm_buf->seq_num =
> -               cpu_to_le16((HostCmd_SET_SEQ_NO_BSS_INFO
> +               cpu_to_le16(HostCmd_SET_SEQ_NO_BSS_INFO
>                                         (adapter->seq_num, priv->bss_num,
> -                                        priv->bss_type)));
> +                                        priv->bss_type));
>
>         mwifiex_dbg(adapter, CMD,
>                     "cmd: DNLD_CMD: %#x, act %#x, len %d, seqno %#x\n",
> diff --git a/drivers/net/wireless/marvell/mwifiex/fw.h b/drivers/net/wireless/marvell/mwifiex/fw.h
> index 8047e307892e..1f02c5058aed 100644
> --- a/drivers/net/wireless/marvell/mwifiex/fw.h
> +++ b/drivers/net/wireless/marvell/mwifiex/fw.h
> @@ -513,10 +513,10 @@ enum mwifiex_channel_flags {
>
>  #define RF_ANTENNA_AUTO                 0xFFFF
>
> -#define HostCmd_SET_SEQ_NO_BSS_INFO(seq, num, type) {   \
> -       (((seq) & 0x00ff) |                             \
> -        (((num) & 0x000f) << 8)) |                     \
> -       (((type) & 0x000f) << 12);                  }
> +#define HostCmd_SET_SEQ_NO_BSS_INFO(seq, num, type) \
> +       ((((seq) & 0x00ff) |                        \
> +        (((num) & 0x000f) << 8)) |                 \
> +       (((type) & 0x000f) << 12))
>
>  #define HostCmd_GET_SEQ_NO(seq)       \
>         ((seq) & HostCmd_SEQ_NUM_MASK)
> --
Kalle Valo Sept. 7, 2020, 8:29 a.m. UTC | #2
Nathan Chancellor <natechancellor@gmail.com> wrote:

> 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@gmail.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

Patch applied to wireless-drivers-next.git, thanks.

6a953dc4dbd1 mwifiex: Remove unnecessary braces from HostCmd_SET_SEQ_NO_BSS_INFO
diff mbox series

Patch

diff --git a/drivers/net/wireless/marvell/mwifiex/cmdevt.c b/drivers/net/wireless/marvell/mwifiex/cmdevt.c
index d068b9075c32..3a11342a6bde 100644
--- a/drivers/net/wireless/marvell/mwifiex/cmdevt.c
+++ b/drivers/net/wireless/marvell/mwifiex/cmdevt.c
@@ -322,9 +322,9 @@  static int mwifiex_dnld_sleep_confirm_cmd(struct mwifiex_adapter *adapter)
 
 	adapter->seq_num++;
 	sleep_cfm_buf->seq_num =
-		cpu_to_le16((HostCmd_SET_SEQ_NO_BSS_INFO
+		cpu_to_le16(HostCmd_SET_SEQ_NO_BSS_INFO
 					(adapter->seq_num, priv->bss_num,
-					 priv->bss_type)));
+					 priv->bss_type));
 
 	mwifiex_dbg(adapter, CMD,
 		    "cmd: DNLD_CMD: %#x, act %#x, len %d, seqno %#x\n",
diff --git a/drivers/net/wireless/marvell/mwifiex/fw.h b/drivers/net/wireless/marvell/mwifiex/fw.h
index 8047e307892e..1f02c5058aed 100644
--- a/drivers/net/wireless/marvell/mwifiex/fw.h
+++ b/drivers/net/wireless/marvell/mwifiex/fw.h
@@ -513,10 +513,10 @@  enum mwifiex_channel_flags {
 
 #define RF_ANTENNA_AUTO                 0xFFFF
 
-#define HostCmd_SET_SEQ_NO_BSS_INFO(seq, num, type) {   \
-	(((seq) & 0x00ff) |                             \
-	 (((num) & 0x000f) << 8)) |                     \
-	(((type) & 0x000f) << 12);                  }
+#define HostCmd_SET_SEQ_NO_BSS_INFO(seq, num, type) \
+	((((seq) & 0x00ff) |                        \
+	 (((num) & 0x000f) << 8)) |                 \
+	(((type) & 0x000f) << 12))
 
 #define HostCmd_GET_SEQ_NO(seq)       \
 	((seq) & HostCmd_SEQ_NUM_MASK)