Re: PATCH: PR corefiles/11511: gcore doesn't work with orig_rax on Linux/amd64

[Mark Kettenis <mark.kettenis@xs4all.nl>]

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> Date: Sat, 17 Apr 2010 11:50:11 -0700
> From: "H.J. Lu" <hjl.tools@gmail.com>
> 
> On Sat, Apr 17, 2010 at 9:25 AM, Mark Kettenis <mark.kettenis@xs4all.nl> wrote:
> >> Date: Sat, 17 Apr 2010 09:11:15 -0700
> >> From: "H.J. Lu" <hongjiu.lu@intel.com>
> >>
> >> This patch adds orig_rax support to amd64_linux_gregset_reg_offset.
> >> amd64 has both tdep->gregset_reg_offset/tdep->gregset_num_regs and
> >> amd64_native_gregset64_reg_offset/amd64_native_gregset64_num_regs.  They
> >> are identical. There is no need to keep both.  This patch also removes
> >> amd64_native_gregset64_reg_offset/amd64_native_gregset64_num_regs. OK
> >> to install?
> >
> > No.  I want to keep the -nat.c and -tdep.c code separate.
> 
> Can I replace amd64_linux_gregset64_reg_offset with
> amd64_linux_gregset_reg_offset, like amd64nbsd-nat.c
> and amd64obsd-nat.c?

We can discuss that, yes.  The way the code is organized now, at least
native debugging will continue to work if the layout of the trap frame
in the Linux kernel were to change.  At least in the past there was
some fear that this would happen.  That danger is probably small; I'm
not even sure if the data structure for PTRACE_GETREGS is even linked
to the trap frame layout anymore.

Of course the benefit of doing so is that if the kernel ABI is ever
broken GDB will completely stop working on Linux instead of just being
partly broken.

Any other people have an opinion about this?