On Mon, 30 Jul 2012, Pekka Enberg wrote:

> > The label oops is used in CONFIG_DEBUG_VM ifdef block and is defined
> > outside ifdef CONFIG_DEBUG_VM block. This results in the following
> > build warning when built with CONFIG_DEBUG_VM disabled. Fix to move
> > label oops definition to inside a CONFIG_DEBUG_VM block.
> >
> > mm/slab_common.c: In function ‘kmem_cache_create’:
> > mm/slab_common.c:101:1: warning: label ‘oops’ defined but not used
> > [-Wunused-label]
> >
> > Signed-off-by: Shuah Khan <shuah.khan@hp.com>
> 
> I merged this as an obvious and safe fix for current merge window. We
> need to clean this up properly for v3.7.
> 

-Wunused-label is overridden in gcc for a label that is conditionally 
referenced by using __maybe_unused in the kernel.  I'm not sure what's so 
obscure about

out: __maybe_unused

Are label attributes really that obsecure?