m32r: fix build warning

Some m32r builds were having a warning:

  arch/m32r/include/asm/cmpxchg.h:191:3: warning: value computed is not used
  arch/m32r/include/asm/cmpxchg.h:68:3: warning: value computed is not used

Taking the idea from commit e001bbae71 ("ARM: cmpxchg: avoid warnings
from macro-ized cmpxchg() implementations") the m32r implementation is
changed to use a similar construct with a compound expression instead of
a typecast, which causes the compiler to not complain about an unused
result.

Link: http://lkml.kernel.org/r/1484432664-7015-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sudip Mukherjee 2017-02-22 15:40:35 -08:00 committed by Linus Torvalds
parent 6408b6fb99
commit af0de7815e

View File

@ -64,8 +64,10 @@ __xchg(unsigned long x, volatile void *ptr, int size)
return (tmp);
}
#define xchg(ptr, x) \
((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
#define xchg(ptr, x) ({ \
((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), \
sizeof(*(ptr)))); \
})
static __always_inline unsigned long
__xchg_local(unsigned long x, volatile void *ptr, int size)
@ -187,9 +189,12 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
return old;
}
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg(ptr, o, n) ({ \
((__typeof__(*(ptr))) \
__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), \
sizeof(*(ptr)))); \
})
#include <asm-generic/cmpxchg-local.h>