This is the mail archive of the
gdb@sourceware.org
mailing list for the GDB project.
Re: Question about ELF core file sections
- From: Mark Kettenis <mark dot kettenis at xs4all dot nl>
- To: randolph at tausq dot org
- Cc: gdb at sources dot redhat dot com
- Date: Wed, 16 Nov 2005 17:14:02 +0100 (CET)
- Subject: Re: Question about ELF core file sections
- References: <437B53B4.5000906@tausq.org>
> Date: Wed, 16 Nov 2005 23:43:48 +0800
> From: Randolph Chung <randolph@tausq.org>
>
> I'm trying to get core file support working on hppa64-hp-hpux11.11. I'm
> trying to reuse the infrastructure from corelow.c and the "new"
> regset_from_core_section() interface, but I'm a bit confused about how
> it's supposed to work.
>
> corelow.c:get_core_registers() is hardcoded to look for registers in
> sections ".reg", ".reg2", ".reg-xfp" -- are these section names somehow
> standard? I don't find these documented in the ELF specs. I see that on
> Linux variants, this ".reg" section is actually synthesized by bfd. This
> all seems to be a bit convoluted :(
The names are largely hostoric (and I'd really like to rename ".reg2"
to something more sensible). The mechanism is there more for the
benefit of binutils than for gdb I think. By synthesising those
section you can inspect and manipulate them with objdump for example.
> On HPUX, there is a program header type HP_CORE_PROC that points to a
> datastructure with the register info. Is there anyway to use the
> existing interface to get to this info? If not, it looks like I can get
> it to work using core_vec, but that uses an interface that is marked
> deprecated....
You'll need to write code in BFD to synthesise the ".reg" and ".reg2"
sections. Code for 32-bit HP-UX (SOM) code files is already there in
bfd/hpux-core.c, but that code doesn't work for cross debugging.
> Any hints and help appreciated...
I think m68kbsd-tdep.c provides a pretty clean implementation
implementation of what needs to implemented on gdb's side. Take a
look at m68kbsd_supply_fpregset() and m68kbsd_supply_gregset(), how
they're used in m68kbsd_gregset and m68kbsd_fpregset, and check out
m68kbsd_regset_from_core_section.
Cheers,
Mark