Hi Josh,
On Fri, 29 Apr 2016 09:03:42 -0500 Josh Poimboeuf <jpoim...@redhat.com> wrote:
>
> On Fri, Apr 29, 2016 at 08:32:19AM -0500, Josh Poimboeuf wrote:
> > On Fri, Apr 29, 2016 at 04:45:43PM +1000, Stephen Rothwell wrote:
> > > Hi Andrew,
> > >
> > > After merging the akpm-current tree, today's linux-next build (x86_64
> > > allmodconfig) produced this warning:
> > >
> > > drivers/scsi/ipr.c: In function 'ipr_show_device_id':
> > > drivers/scsi/ipr.c:4462:34: warning: format '%llx' expects argument of
> > > type 'long long unsigned int', but argument 4 has type 'long unsigned
> > > int' [-Wformat=]
> > > len = snprintf(buf, PAGE_SIZE, "0x%llx\n", be64_to_cpu(res->dev_id));
> > > ^
> > >
> > > Lots and lots like this :-(
> > >
> > > Probably introduced by commit
> > >
> > > eef17fb79096 ("byteswap: try to avoid __builtin_constant_p gcc bug")
> > >
> > > I guess __builtin_bswap64() has type "unsigned long int" :-(
> >
> > Hm, I suppose this is cross-compiled on a powerpc host?
> >
> > We probably need to add a (__u64) cast to the return value of
> > __builtin_bswap64(), like:
> >
> > diff --git a/include/uapi/linux/swab.h b/include/uapi/linux/swab.h
> > index de56fd5..d737804 100644
> > --- a/include/uapi/linux/swab.h
> > +++ b/include/uapi/linux/swab.h
> > @@ -123,7 +123,7 @@ static inline __attribute_const__ __u32
> > __fswahb32(__u32 val)
> > * @x: value to byteswap
> > */
> > #ifdef __HAVE_BUILTIN_BSWAP64__
> > -#define __swab64(x) __builtin_bswap64((__u64)(x))
> > +#define __swab64(x) (__u64)__builtin_bswap64((__u64)(x))
> > #else
> > #define __swab64(x) \
> > (__builtin_constant_p((__u64)(x)) ? \
>
>
> Never mind about cross-compiling on powerpc, this has nothing to do with
> that. But the above patch does seem to fix it.
Thanks. I have added Andrew's tidied up version to linux-next to
replace the revert.
--
Cheers,
Stephen Rothwell
