Collecting description of types from symbol table

Collecting description of types from symbol table

[Vimal]

I would like to dump the collect the output of the "ptype" command for
all possible types that gdb is aware of.

For example, the following output is very useful when debugging the
kernel, and I would like to collect the output of all such types in
the kernel for reference.   Could someone tell me rough ideas of how
this is stored in the executable, and how to dump this?

(gdb) ptype raw_spinlock_t
type = struct raw_spinlock {
    arch_spinlock_t raw_lock;
    unsigned int magic;
    unsigned int owner_cpu;
    void *owner;
    struct lockdep_map dep_map;
}

Thanks,
-- 
Vimal

Re: Collecting description of types from symbol table

[Tom Tromey]

>>>>> "Vimal" == Vimal  <j.vimal@gmail.com> writes:

Vimal> I would like to dump the collect the output of the "ptype" command for
Vimal> all possible types that gdb is aware of.

Vimal> For example, the following output is very useful when debugging the
Vimal> kernel, and I would like to collect the output of all such types in
Vimal> the kernel for reference.   Could someone tell me rough ideas of how
Vimal> this is stored in the executable, and how to dump this?

Usually it is stored in DWARF format.
See http://dwarfstd.org/

Iterating over all the types, in gdb, is not trivial.
It could be done but you will have to write some C code to do it.

The 7 dwarves project would be an ok place to start for this though.
pahole nearly does it already.

Tom

Re: Collecting description of types from symbol table

[Vimal]

Hi Tom,

On 5 March 2012 08:36, Tom Tromey <tromey@redhat.com> wrote:
>
> Usually it is stored in DWARF format.
> See http://dwarfstd.org/
>
> Iterating over all the types, in gdb, is not trivial.
> It could be done but you will have to write some C code to do it.

DWARF standard pointed me to dwarfdump, which seems to dump the type
information stored in an object file.

> The 7 dwarves project would be an ok place to start for this though.
> pahole nearly does it already.

pahole is interesting, but it looks like its repository on kernel.org
is down.  I'll contact the author.

Thanks!
-- 
Vimal

Re: Collecting description of types from symbol table

[Tom Tromey]

>>>>> "Vimal" == Vimal  <j.vimal@gmail.com> writes:

Vimal> DWARF standard pointed me to dwarfdump, which seems to dump the type
Vimal> information stored in an object file.

You probably already have readelf, eu-readelf, and/or objdump installed
on your system, all of which can dump DWARF.  They don't emit it in C
style though.

Vimal> pahole is interesting, but it looks like its repository on kernel.org
Vimal> is down.  I'll contact the author.

Most distros package it.

Tom

Re: Collecting description of types from symbol table

[Vimal]

On 6 March 2012 19:14, Tom Tromey <tromey@redhat.com> wrote:
> Vimal> pahole is interesting, but it looks like its repository on kernel.org
> Vimal> is down.  I'll contact the author.
>
> Most distros package it.

Thanks, I found it in dwarves package on Debian.

-- 
Vimal