Re: AIX DWARF debugging sections

Joel Brobecker
2015-10-12T15:50:26Z

> >> I'm not really sure how to best proceed, here. On the one hand,
> >> IBM can be considered the authority on these kinds of questions.
> >> On the other hand, GDB being a GNU tool, we should probably make
> >> it easier to debug code produced by GNU tools rather than by
> >> propriatery ones... It's particularly tempting since GNU as
> >> has chosen different section names, which seems to be a better
> >> choice to me, and also happens to make it easier on the code.
> >
> >
> > Agreed.
>
> Not agreed.
>
> AIX has a definition of DWARF on the platform. Adacore invented an
> incompatible definition of DWARF on AIX (and has known about the
> correct definition since 2011). How can GDB developers argue for
> conformance with various standards, but ignore the definitions and
> documentation of AIX?

Unfortunately, David is right. I personally hadn't known about AIX's
definition of DWARF, but it doesn't matter. I thought we had contributed
our patches by now, but it appears it's been stalled due to some
technical issues that Tristan didn't want to spend time on, and that
therefore, submission has only been partial.

So IBM's definition should be considered as reference, and AdaCore
will have to deal with whatever happens because of it.

> AIX XLC apparently will not utilize .dwmac macro section until DWARF5
> to encore the .debug_macro section, so GCC and GDB should utilize it
> as .debug_macro and not produce or consume .debug_macinfo.

OK, if macinfo data cannot be generated by XLC, then it would make
sense to me to just ammend your patch to only update the .debug_macro
entry. If that's correct, then that avoids the concern I had about
having two entries with the same section name.

--
Joel