Re: [rfa:solib] Handle start-address descriptors

[Andrew Cagney <ac131313 at redhat dot com>]

> On Oct 27,  1:45pm, Andrew Cagney wrote:
>
>
> > Index: solib-svr4.c
>
> ...
>
> > +#include "bfd-target.h"
> > +#include "exec.h"
>
>
> I'm surprised that you needed to include exec.h.  solib-svr4.c already
> includes target.h and I would've thought this to be sufficient.  If
> exec.h isn't needed, please take it out.  (Don't forget to fix Makefile.in.)

They are both needed.

> > +/* Given an executable's ABFD and target, compute the entry-point
> > +   address.  */
> > +
> > +static CORE_ADDR
> > +exec_entry_point (struct bfd *abfd, struct target_ops *targ)
> > +{
>
>
> Could you add a comment here telling why
> gdbarch_convert_from_func_ptr_addr() is needed.  Maybe something like
> this?

I'll add your comment.

>   /* For most targets, the address returned by bfd_get_start_address()
>      is the entry point for the start function.  But, for some targets,
>      bfd_get_start_address() returns the address of a function descriptor
>      from which the entry point address may be extracted.  This address
>      is extracted by gdbarch_convert_from_func_ptr_addr().  The method
>      gdbarch_convert_from_func_ptr_addr() is the merely the identify
>      function for targets which don't use function descriptors.  */
>
> Hmm, a possible problem...  What happens when the target uses function
> descriptors, but not for the exec file's start address?  I'm wondering
> (ugh) if a separate gdbarch method is required for obtaining the start
> address.

Fortunatly a previous patch addressed that problem.  The convert 
function is only applied to positively identified descriptors.

> > +  return gdbarch_convert_from_func_ptr_addr (current_gdbarch,
> > +					     bfd_get_start_address (abfd),
> > +					     targ);
> > +}

Andrew