Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation

[Stefan Weil]

Am 01.11.2010 20:51, schrieb Alexander Graf:
> On 01.11.2010, at 14:42, Stefan Weil wrote:
>
>    
> > Am 01.11.2010 19:29, schrieb Blue Swirl:
> >      
> > > On Mon, Nov 1, 2010 at 3:01 PM, Alexander Graf<address@hidden>   wrote:
> > >
> > >        
> > > > ---
> > > >   hw/elf_ops.h |   61 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> > > >   hw/loader.c  |    7 ++++++
> > > >   hw/loader.h  |    3 ++
> > > >   3 files changed, 70 insertions(+), 1 deletions(-)
> > > >
> > > > diff --git a/hw/elf_ops.h b/hw/elf_ops.h
> > > > index 8b63dfc..645d058 100644
> > > > --- a/hw/elf_ops.h
> > > > +++ b/hw/elf_ops.h
> > > > @@ -189,6 +189,44 @@ static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int 
> > > > fd, int must_swab,
> > > >      return -1;
> > > >   }
> > > >
> > > > +static void glue(elf_read_notes, SZ)(uint8_t *data, int data_len,
> > > > +                                     ElfHandlers *handlers, int must_swab)
> > > > +{
> > > > +    uint8_t *p = data;
> > > > +
> > > > +    while ((ulong)&p[3]<   (ulong)&data[data_len]) {
> > > >
> > > >          
> > > Please use 'unsigned long'.
> > >
> > >        
> > Why is a type cast used here? I see no reason for it.
> >      
> Pointers can't be compared, you have to cast them to values first.
>
>
> Alex
>    

No. Pointers of same type which are not void pointers can be compared.

There is even a data type ptrdiff_t, so you can also compare their
difference with zero.

Regards,
Stefan