On Thu, 08 Jun 2017 09:28:37 +0200, Takashi Sakamoto wrote: > > Hi, > > On Jun 8 2017 16:10, Takashi Iwai wrote: > > On Thu, 08 Jun 2017 01:10:19 +0200, > > Takashi Sakamoto wrote: > >> > >> Application of constraints to mask-type parameters for PCM substream is > >> done in a call of snd_pcm_hw_refine(), while the function includes much > >> codes and is not enough friendly to readers. > >> > >> This commit splits the codes to a separated function so that readers can > >> get it easily. I leave desicion into compilers to merge the function into > >> its callee. > >> > >> Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx> > >> --- > >> sound/core/pcm_native.c | 57 ++++++++++++++++++++++++++++++++----------------- > >> 1 file changed, 38 insertions(+), 19 deletions(-) > >> > >> diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c > >> index 2bde07a4a87f..b3e8aab3915e 100644 > >> --- a/sound/core/pcm_native.c > >> +++ b/sound/core/pcm_native.c > >> ... > >> + struct snd_mask __maybe_unused old_mask; > > > > Do we really need __maybe_unused? Drop it as much as possible. > > IMO, it can be uglier than ifdef, since you don't know why it's > > unused. With ifdef, at least, you have an idea about the condition. > > In kernel documentation[1], we can see below suggestion. > > "20) Conditional Compilation > ... > 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. (However, if a > function or variable *always* goes unused, delete it.)" > > I'll follow this. It doesn't answer my question. Without __maybe_unused in your code, do you get the compile warning? If yes, why? Well, I see the usage already in your patch for the tracepoints. But __maybe_unused is really ugly, and should be avoided as much as possible. The text above doesn't recommend to use it blindly. It's the last resort. thanks, Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
