Re: ld corrupting .cfi_label uses

["Jan Beulich" <JBeulich at suse dot com>]

>>> On 08.03.17 at 22:52, <amodra@gmail.com> wrote:
> On Wed, Mar 08, 2017 at 07:33:07AM -0700, Jan Beulich wrote:
>> >>> On 08.03.17 at 15:12, <amodra@gmail.com> wrote:
>> > On Fri, Mar 03, 2017 at 01:37:17AM -0700, Jan Beulich wrote:
>> >> My problem here is that I don't see any way to know whether
>> >> there are symbols (including local ones, but excluding the
>> >> section one) or relocations referring to a particular section
>> >> (other than going through the raw object file of course), for
>> >> easy checking in _bfd_elf_write_section_eh_frame(), or
>> >> even better already in _bfd_elf_parse_eh_frame_entry().
>> > 
>> > Here's a prototype patch.  It hasn't had much testing, and needs a few
>> > testcases added, particularly for labels in odd parts of a CIE or FDE.
>> > If you could run with this, that would be good.
>> 
>> Thanks for doing this, but going over the patch I can't seem to spot
>> where (generally section symbol relative) relocations are being
>> taken care of. Am I simply overlooking something? I ask because
>> that's the main problem for my use case, whereas symbols don't
>> really matter for the moment (I simply didn't have a need to create
>> any so far).
> 
> The S_FORCE_RELOC change will result in relocations against local
> symbols not being converted to relocations against a section symbol,
> and it should also result in a reloc beins emitted even for references
> within .eh_frame.  (The latter is one of the things I haven't tested.
> There will be a reloc if the reference crosses a frag, I'm not so sure
> if within the same frag.  Also, the section test may need to be
> !strict.)

I'm sorry for not having got back to you on this so far. The issue
I've run into here is in a sideband project of mine, and for now I
can't really predict when I'll be able to spend some more time on
this.

Jan