Re: Why does mips define elf_backend_sign_extend_vma to true?

["H . J . Lu" <hjl@lucon.org>]

On Tue, Aug 07, 2001 at 06:45:04PM -0700, H . J . Lu wrote:
> On Tue, Aug 07, 2001 at 09:42:24PM -0400, Andrew Cagney wrote:
> > > On Tue, Aug 07, 2001 at 06:24:59PM -0700, H . J . Lu wrote:
> > > 
> > >> Only elf32-mips.c has
> > >> 
> > >> #define elf_backend_sign_extend_vma        true
> > >> 
> > >> and we get
> > >> 
> > >> # nm vmlinux
> > >> ffffffff802e01f0 D C_A_D
> > >> ffffffff802df344 D EISA_bus
> > >> ....
> > >> 
> > >> Does anyone know why mips does this?
> > >> 
> > > 
> > > 
> > > It seems that it was done on purpose:
> > > 
> > > http://sources.redhat.com/ml/binutils/1999-11/msg00080.html
> > > 
> > > I don't believe it is correct for the normal 32bit MIPS SVR4 ABI. I'd like
> > > to turn it off. If you want to do sign extension, you should create a new
> > > ABI, not break the existing ABI.
> > 
> > 
> > Several ABI's have implied sign extension of addresses.  MIPS is one.
> > 
> 
> Show me where it is documemnted in the 32bit SVR4 MIPS ABI.
> 

FYI, some prorgams using bfd are broken on Linux/mips because of this: nm,
objdump and gdb. In gdb

# gdb vmlinux
...
(gdb) list printk
1874
1875    static void __exit packet_exit(void)
1876    {
1877            remove_proc_entry("net/packet", 0);
1878            unregister_netdevice_notifier(&packet_netdev_notifier);
1879            sock_unregister(PF_PACKET);
1880            return;
1881    }
1882
1883    static int __init packet_init(void)


H.J.