[Bug target/27363] ARM gcc 4.1 optimization bug

Until a fix for this bug is found, there are two possible workarounds:

- Compile kernels sound system as modules and compile these modules with
  -O1 instead of default -Os or -O2 (e.g. by changing main Makefile).

- Use this patch from Fengwei Yin <yfw.debian@gmail.com> (then -Os or -O2
  should work).

See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27363 for details.
Signed-off-by: Fengwei Yin <yfw.debian@gmail.com>

include/sound/pcm_params.h

@@ -196,6 +196,8 @@ INLINE int snd_mask_refine(struct snd_mask *mask, const struct snd_mask *v)
 	struct snd_mask old;
 	assert(!snd_mask_empty(mask));
 	snd_mask_copy(&old, mask);
+	/* add the barrier to fix the optimization error if GCC 4.1 */
+	mb();
 	snd_mask_intersect(mask, v);
 	if (snd_mask_empty(mask))
 		return -EINVAL;