| Message ID | 20181213154257.23033-1-Eugeniy.Paltsev@synopsys.com |
|---|---|
| State | New |
| Headers | show |
| Series | ARC: fix __ffs return value to avoid build warnings | expand |
On 12/13/18 7:43 AM, Eugeniy Paltsev wrote: > Change __ffs return value from 'int' to 'unsigned long' as it > is done in other implementations (like asm-generic, x86, etc...) > to avoid build-time warnings in places where type is strictly > checked. > > As __ffs may return values in [0-31] interval changing return > type to unsigned is valid. > > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Can you please paste a couple of lines of offending output ! -Vineet
Hi Vineet, On Thu, 2018-12-13 at 18:23 +0000, Vineet Gupta wrote: > On 12/13/18 7:43 AM, Eugeniy Paltsev wrote: > > Change __ffs return value from 'int' to 'unsigned long' as it > > is done in other implementations (like asm-generic, x86, etc...) > > to avoid build-time warnings in places where type is strictly > > checked. > > > > As __ffs may return values in [0-31] interval changing return > > type to unsigned is valid. > > > > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> > > Can you please paste a couple of lines of offending output ! ---------------------------------->8--------------------------------- CC mm/nobootmem.o In file included from ./include/asm-generic/bug.h:18:0, from ./arch/arc/include/asm/bug.h:32, from ./include/linux/bug.h:5, from ./include/linux/mmdebug.h:5, from ./include/linux/gfp.h:5, from ./include/linux/slab.h:15, from mm/nobootmem.c:14: mm/nobootmem.c: In function ‘__free_pages_memory’: ./include/linux/kernel.h:845:29: warning: comparison of distinct pointer types lacks a cast (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ^ ./include/linux/kernel.h:859:4: note: in expansion of macro ‘__typecheck’ (__typecheck(x, y) && __no_side_effects(x, y)) ^~~~~~~~~~~ ./include/linux/kernel.h:869:24: note: in expansion of macro ‘__safe_cmp’ __builtin_choose_expr(__safe_cmp(x, y), \ ^~~~~~~~~~ ./include/linux/kernel.h:878:19: note: in expansion of macro ‘__careful_cmp’ #define min(x, y) __careful_cmp(x, y, <) ^~~~~~~~~~~~~ mm/nobootmem.c:104:11: note: in expansion of macro ‘min’ order = min(MAX_ORDER - 1UL, __ffs(start)); ^~~ ---------------------------------->8--------------------------------- > > -Vineet
diff --git a/arch/arc/include/asm/bitops.h b/arch/arc/include/asm/bitops.h index 8da87feec59a..99e6d8948f4a 100644 --- a/arch/arc/include/asm/bitops.h +++ b/arch/arc/include/asm/bitops.h @@ -340,7 +340,7 @@ static inline __attribute__ ((const)) int __fls(unsigned long x) /* * __ffs: Similar to ffs, but zero based (0-31) */ -static inline __attribute__ ((const)) int __ffs(unsigned long word) +static inline __attribute__ ((const)) unsigned long __ffs(unsigned long word) { if (!word) return word; @@ -400,9 +400,9 @@ static inline __attribute__ ((const)) int ffs(unsigned long x) /* * __ffs: Similar to ffs, but zero based (0-31) */ -static inline __attribute__ ((const)) int __ffs(unsigned long x) +static inline __attribute__ ((const)) unsigned long __ffs(unsigned long x) { - int n; + unsigned long n; asm volatile( " ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */
Change __ffs return value from 'int' to 'unsigned long' as it is done in other implementations (like asm-generic, x86, etc...) to avoid build-time warnings in places where type is strictly checked. As __ffs may return values in [0-31] interval changing return type to unsigned is valid. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> --- arch/arc/include/asm/bitops.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)