Subject: Re: [PATCH] Make u64 long long on all architectures (was: the printk problem)

From: Michael Ellerman <[email-masked]>
Date: Tue, 22 Jul 2008 20:36:35 +1000

On Tue, 2008-07-22 at 03:05 -0700, Andrew Morton wrote:
> On Fri, 4 Jul 2008 20:03:51 -0600 Matthew Wilcox <[email-masked]> wrote:
> 
> > [PATCH] Make u64 long long on all architectures
> > 
> > It is currently awkward to print a u64 type.  Some architectures use
> > unsigned long while others use unsigned long long.  Since unsigned long
> > long is 64-bit for all existing Linux architectures, change those that
> > use long to use long long.  Note that this applies only within the
> > kernel.  If u64 is being used in a C++ method definition, the symbol
> > mangling would change.
> > 
> > Signed-off-by: Matthew Wilcox <[email-masked]>
> > 
> > diff --git a/include/asm-generic/int-l64.h b/include/asm-generic/int-l64.h
> > index 2af9b75..32f07bd 100644
> > --- a/include/asm-generic/int-l64.h
> > +++ b/include/asm-generic/int-l64.h
> > @@ -23,8 +23,13 @@ typedef unsigned short __u16;
> >  typedef __signed__ int __s32;
> >  typedef unsigned int __u32;
> >  
> > +#ifdef __KERNEL__
> > +typedef __signed__ long long __s64;
> > +typedef unsigned long long __u64;
> > +#else
> >  typedef __signed__ long __s64;
> >  typedef unsigned long __u64;
> > +#endif
> >  
> >  #endif /* __ASSEMBLY__ */
> 
> This is (IMO) a desirable change and will prevent a heck of a lot of
> goofing around, and will permit a lot of prior goofing around to
> be removed.
> 
> But I bet there are lots of instalces of printk("%l", some_u64) down in
> arch code where the type of u64 _is_ known which will now spew warnings.
> 
> Oh well.

As a rough estimate:

concordia powerpc(master) $ find arch/powerpc/ ! -name '*32.*' | xargs grep "%l" | grep -v "%ll" | wc -l
635

Someone's gonna get a lot of git points for fixing all those. Might keep
the speeling fix crowd busy for a while.

cheers

-- 
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person