[PATCH] ALSA: firewire-motu: mark trace helpers as __maybe_unused

[PATCH] ALSA: firewire-motu: mark trace helpers as __maybe_unused

[Arnd Bergmann]

Two functions were introduced for the purpose of tracing but cause warnings
when tracing is disabled:

sound/firewire/motu/amdtp-motu.c:284:13: error: 'copy_message' defined but not used [-Werror=unused-function]
 static void copy_message(u64 *frames, __be32 *buffer, unsigned int data_blocks,
sound/firewire/motu/amdtp-motu.c:271:13: error: 'copy_sph' defined but not used [-Werror=unused-function]
 static void copy_sph(u32 *frames, __be32 *buffer, unsigned int data_blocks,

Marking them as __maybe_unused will do the right thing here.

Fixes: 17909c1b3058 ("ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion")
Fixes: c6b0b9e65f09 ("ALSA: firewire-motu: add tracepoints for messages for unique protocol")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 sound/firewire/motu/amdtp-motu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
index 996b5f818918..96f0091144bb 100644
--- a/sound/firewire/motu/amdtp-motu.c
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -268,8 +268,9 @@ static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 }
 
 /* For tracepoints. */
-static void copy_sph(u32 *frames, __be32 *buffer, unsigned int data_blocks,
-		     unsigned int data_block_quadlets)
+static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
+				    unsigned int data_blocks,
+				    unsigned int data_block_quadlets)
 {
 	unsigned int i;
 
@@ -281,8 +282,9 @@ static void copy_sph(u32 *frames, __be32 *buffer, unsigned int data_blocks,
 }
 
 /* For tracepoints. */
-static void copy_message(u64 *frames, __be32 *buffer, unsigned int data_blocks,
-			 unsigned int data_block_quadlets)
+static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
+					unsigned int data_blocks,
+					unsigned int data_block_quadlets)
 {
 	unsigned int i;
 
-- 
2.9.0

Re: [PATCH] ALSA: firewire-motu: mark trace helpers as __maybe_unused

[Takashi Iwai]

On Wed, 19 Apr 2017 19:51:29 +0200,
Arnd Bergmann wrote:
> 
> Two functions were introduced for the purpose of tracing but cause warnings
> when tracing is disabled:
> 
> sound/firewire/motu/amdtp-motu.c:284:13: error: 'copy_message' defined but not used [-Werror=unused-function]
>  static void copy_message(u64 *frames, __be32 *buffer, unsigned int data_blocks,
> sound/firewire/motu/amdtp-motu.c:271:13: error: 'copy_sph' defined but not used [-Werror=unused-function]
>  static void copy_sph(u32 *frames, __be32 *buffer, unsigned int data_blocks,
> 
> Marking them as __maybe_unused will do the right thing here.
> 
> Fixes: 17909c1b3058 ("ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion")
> Fixes: c6b0b9e65f09 ("ALSA: firewire-motu: add tracepoints for messages for unique protocol")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Applied, thanks.


Takashi

Re: [PATCH] ALSA: firewire-motu: mark trace helpers as __maybe_unused

[Takashi Iwai]

On Thu, 20 Apr 2017 14:52:13 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> On 2017年04月20日 19:51, Takashi Iwai wrote:
> > On Wed, 19 Apr 2017 19:51:29 +0200,
> > Arnd Bergmann wrote:
> >>
> >> Two functions were introduced for the purpose of tracing but cause warnings
> >> when tracing is disabled:
> >>
> >> sound/firewire/motu/amdtp-motu.c:284:13: error: 'copy_message' defined but not used [-Werror=unused-function]
> >>  static void copy_message(u64 *frames, __be32 *buffer, unsigned int data_blocks,
> >> sound/firewire/motu/amdtp-motu.c:271:13: error: 'copy_sph' defined but not used [-Werror=unused-function]
> >>  static void copy_sph(u32 *frames, __be32 *buffer, unsigned int data_blocks,
> >>
> >> Marking them as __maybe_unused will do the right thing here.
> >>
> >> Fixes: 17909c1b3058 ("ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion")
> >> Fixes: c6b0b9e65f09 ("ALSA: firewire-motu: add tracepoints for messages for unique protocol")
> >> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> >
> > Applied, thanks.
> 
> Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
> 
> I note that Documentation/process/coding-style.rst describes:
> 'If you have a function or variable which may potentially go unused in a
> particular configuration, and the compiler would warn about its
> definition going unused, mark the definition as __maybe_unused rather
> than wrapping it in a preprocessor conditional.'
> 
> Iwa-san, could I request you to apply below patch in the last week of
> this development period?
> http://mailman.alsa-project.org/pipermail/alsa-devel/2017-April/119806.html

Merged now, sorry for overlooking it.


thanks,

Takashi