Re: question about GDB message

On 9/25/07, Daniel Jacobowitz <drowfalse.org> wrote:
> On Tue, Sep 25, 2007 at 05:27:13AM -0700, The
Westlakers wrote:
> > So I did this:
> >
> > ./configure --target=sparc64-elf, is this right?
the resulting GDB
> > becomes 32-bit app
> > and it can talk to the target in 32-mode, but not
64-bit.
> >
> > Maybe you could help to make sure I configured it
right.
>
> That's right.  It shouldn't matter that the GDB is
32-bit.  What goes
> wrong talking to a 64-bit target?

when GDB issues 'g' packet to the target, the target returns
all reg
values in 64-bit,
but the GDB interprets it as 32-bit, so 'info reg' will not
show
correct register values.
if the target returns in 32-bit values, then info reg can
display all
values correctly.

do not know what is wrong.

thanks
>
> --
> Daniel Jacobowitz
> CodeSourcery
>

On Tue, Sep 25, 2007 at 08:57:47AM -0700, The Westlakers
wrote:
> > That's right.  It shouldn't matter that the GDB is
32-bit.  What goes
> > wrong talking to a 64-bit target?
> 
> when GDB issues 'g' packet to the target, the target
returns all reg
> values in 64-bit,
> but the GDB interprets it as 32-bit, so 'info reg' will
not show
> correct register values.
> if the target returns in 32-bit values, then info reg
can display all
> values correctly.

Did you load a 64-bit file into GDB so that it knows you are
debugging
a 64-bit image?

-- 
Daniel Jacobowitz
CodeSourcery