audio_format: volatile removal

volatile provides absolutely no guarantee thread-safety in SMP
environments.  volatile was designed to access memory locations
in peripheral hardware directly; not for SMP.  If volatile is
needed to work properly on SMP, then it is only hiding subtle
bugs.

volatile only prevents the /compiler/ from making optimizations
when accessing variables.  CPUs do their own optimizations at
runtime so it cannot guarantee registers of CPUs are flushed
to memory cache-coherent access on different CPUs.

Furthermore, the thread-communication via condition variables
between threads sharing audio formats already results in memory
barriers.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/audio_format.h b/src/audio_format.h
index a6e97e04..ade9d881 100644
--- a/src/audio_format.h
+++ b/src/audio_format.h
@@ -22,9 +22,9 @@
 #include "mpd_types.h"
 
 typedef struct _AudioFormat {
-	volatile mpd_sint8 channels;
-	volatile mpd_uint32 sampleRate;
-	volatile mpd_sint8 bits;
+	mpd_sint8 channels;
+	mpd_uint32 sampleRate;
+	mpd_sint8 bits;
 } AudioFormat;
 
 static inline double audio_format_time_to_size(const AudioFormat * af)