[alsa-devel] [PATCH 1/2] ALSA: pcm: use "do {} while (0)" for empty macro
Recent compilers produce a harmless warning for the new pcm_call_notify() macro when CONFIG_SND_PCM_OSS is disabled:
sound/core/pcm.c: In function 'snd_pcm_free': sound/core/pcm.c:905:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
This turns the empty macro into a 'do {} while (0)' statement to avoid the warning.
Fixes: 58f30d650c7f ("ALSA: pcm: Build pcm notifier code conditionally") Signed-off-by: Arnd Bergmann arnd@arndb.de --- sound/core/pcm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/core/pcm.c b/sound/core/pcm.c index 24acbfb5c531..d30dba0ee688 100644 --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -894,7 +894,7 @@ static void snd_pcm_free_stream(struct snd_pcm_str * pstr) _notify->call(pcm); \ } while (0) #else -#define pcm_call_notify(pcm, call) /* NOP */ +#define pcm_call_notify(pcm, call) do {} while (0) #endif
static int snd_pcm_free(struct snd_pcm *pcm)
Only one of the two declarations has the const modifier in the argument list, so we get a warning when CONFIG_SND_PCM_OSS_PLUGINS is disabled:
sound/core/oss/pcm_oss.c: In function 'snd_pcm_oss_change_params': sound/core/oss/pcm_oss.c:898:47: error: passing argument 2 of 'snd_pcm_plug_slave_format' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
This makes the two declarations match again.
Fixes: e76bf3c4b4e4 ("ALSA: pcm/oss: refer to parameters instead of copying to reduce usage of kernel stack") Signed-off-by: Arnd Bergmann arnd@arndb.de --- sound/core/oss/pcm_plugin.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/core/oss/pcm_plugin.h b/sound/core/oss/pcm_plugin.h index 38e2c14cb893..73c068abaca5 100644 --- a/sound/core/oss/pcm_plugin.h +++ b/sound/core/oss/pcm_plugin.h @@ -172,7 +172,7 @@ snd_pcm_sframes_t snd_pcm_oss_readv3(struct snd_pcm_substream *substream,
static inline snd_pcm_sframes_t snd_pcm_plug_client_size(struct snd_pcm_substream *handle, snd_pcm_uframes_t drv_size) { return drv_size; } static inline snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *handle, snd_pcm_uframes_t clt_size) { return clt_size; } -static inline int snd_pcm_plug_slave_format(int format, struct snd_mask *format_mask) { return format; } +static inline int snd_pcm_plug_slave_format(int format, const struct snd_mask *format_mask) { return format; }
#endif
Hi,
On May 18 2017 22:35, Arnd Bergmann wrote:
Only one of the two declarations has the const modifier in the argument list, so we get a warning when CONFIG_SND_PCM_OSS_PLUGINS is disabled:
sound/core/oss/pcm_oss.c: In function 'snd_pcm_oss_change_params': sound/core/oss/pcm_oss.c:898:47: error: passing argument 2 of 'snd_pcm_plug_slave_format' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
This makes the two declarations match again.
Fixes: e76bf3c4b4e4 ("ALSA: pcm/oss: refer to parameters instead of copying to reduce usage of kernel stack") Signed-off-by: Arnd Bergmann arnd@arndb.de
sound/core/oss/pcm_plugin.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Indeed. I overlooked that it's conditional...
Reviewed-by: Takashi Sakamoto o-takashi@sakamocchi.jp
diff --git a/sound/core/oss/pcm_plugin.h b/sound/core/oss/pcm_plugin.h index 38e2c14cb893..73c068abaca5 100644 --- a/sound/core/oss/pcm_plugin.h +++ b/sound/core/oss/pcm_plugin.h @@ -172,7 +172,7 @@ snd_pcm_sframes_t snd_pcm_oss_readv3(struct snd_pcm_substream *substream,
static inline snd_pcm_sframes_t snd_pcm_plug_client_size(struct snd_pcm_substream *handle, snd_pcm_uframes_t drv_size) { return drv_size; } static inline snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *handle, snd_pcm_uframes_t clt_size) { return clt_size; } -static inline int snd_pcm_plug_slave_format(int format, struct snd_mask *format_mask) { return format; } +static inline int snd_pcm_plug_slave_format(int format, const struct snd_mask *format_mask) { return format; }
#endif
Thanks :D
Takashi Sakamoto
On Thu, 18 May 2017 15:35:54 +0200, Arnd Bergmann wrote:
Recent compilers produce a harmless warning for the new pcm_call_notify() macro when CONFIG_SND_PCM_OSS is disabled:
sound/core/pcm.c: In function 'snd_pcm_free': sound/core/pcm.c:905:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
This turns the empty macro into a 'do {} while (0)' statement to avoid the warning.
Fixes: 58f30d650c7f ("ALSA: pcm: Build pcm notifier code conditionally") Signed-off-by: Arnd Bergmann arnd@arndb.de
Thanks, applied both patches now.
Takashi
sound/core/pcm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/core/pcm.c b/sound/core/pcm.c index 24acbfb5c531..d30dba0ee688 100644 --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -894,7 +894,7 @@ static void snd_pcm_free_stream(struct snd_pcm_str * pstr) _notify->call(pcm); \ } while (0) #else -#define pcm_call_notify(pcm, call) /* NOP */ +#define pcm_call_notify(pcm, call) do {} while (0) #endif
static int snd_pcm_free(struct snd_pcm *pcm)
2.9.0
participants (3)
-
Arnd Bergmann -
Takashi Iwai -
Takashi Sakamoto