On 01/14/2015 11:47 AM, Mark Wielaard wrote:
On Wed, 2015-01-14 at 09:26 -0500, Jason P. Leasure wrote:
> The type_offset of a type unit header is relative to the beginning
> of the type unit header.
>
> Signed-off-by: Jason P. Leasure <jpleasu(a)super.org>
> ---
> libdw/dwarf_formref_die.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/libdw/dwarf_formref_die.c b/libdw/dwarf_formref_die.c
> index 63f6697..8b92e22 100644
> --- a/libdw/dwarf_formref_die.c
> +++ b/libdw/dwarf_formref_die.c
> @@ -95,7 +95,7 @@ dwarf_formref_die (attr, result)
>
> datap = cu->dbg->sectiondata[IDX_debug_types]->d_buf;
> size = cu->dbg->sectiondata[IDX_debug_types]->d_size;
> - offset = cu->type_offset;
> + offset = cu->start + cu->type_offset;
Thanks, I believe this is correct. I am surprised we didn't encounter
this earlier. Do you happen to have a testcase for it?
Cheers,
Mark
Sorry, I don't have a good testcase, but you can generate a binary with
two type units in the debug_types section using:
echo 'struct A{ struct B {} x;};int main(){A a;return 0;}' | g++ -x
c++ -g -fdebug-types-section -
to see the global die offsets:
dwarfdump -Gi ./a.out
Jason