[RFC] libdw: prepend current directory in read_srclines

[Torsten Polle]

Hi Mark,

> Am 27.03.2017 um 22:45 schrieb Mark Wielaard <mark@klomp.org>:
> 
> Hi Torsten,
> 
> On Sun, Mar 26, 2017 at 08:35:50PM +0200, Torsten Polle wrote:
>> I observed that readelf and elfutils sometimes report different results.
> 
> Do you have an example of this? It would be good to have a testcase.
> 
>> PFA a patch that corrects this. I’m not sure whether the way I tackled
>> the problem is acceptable.
> 
> I see why you are proposing this. The DWARF spec does say about the
> include_directories "Each path entry is either a full path name or is
> relative to the current directory of the compilation". So your patch
> does make sense.
> 
> But it does depend on what users of dwarf_getsrclines expect.
> Or any use of Dwarf_Line/Dwarf_Files. I think those users expect that
> the returned file names can be relative. And that they should make them
> absolute using index zero or the comp_dir themselves.
> 
> So if you do have an example where the expected output isn't what you
> believe it should be we should examine if there is some other way to
> do the right thing.
> 
> Cheers,
> Mark

thanks for the answer. I’ll come back with an example, which is SystemTap based. :-)

Please allow for some delay. I expect to provide an example in about two weeks.

Regards,
Torsten