Re: [PATCH][v2] Always default to DWARF2_DEBUG if not specified, warn about deprecated STABS

[Koning, Paul via Gcc-patches]

> On Sep 13, 2021, at 3:31 AM, Richard Biener <rguent...@suse.de> wrote:
> 
> This makes defaults.h choose DWARF2_DEBUG if PREFERRED_DEBUGGING_TYPE
> is not specified by the target and NO_DEBUG if DWARF is not supported.
> 
> It also makes us warn when STABS is enabled and removes the corresponding
> diagnostic from the Ada frontend.  The warnings are pruned from the
> testsuite output via prune_gcc_output.
> 
> This leaves the following targets without debug support:
> 
> pdp11-*-*   pdp11 is a.out, dwarf support is difficult

I'll admit that I don't know much about debug formats.  It is definitely the 
case that pdp11 output is a.out (it may be BSD 2.x style a.out -- which I think 
is somewhat different though it's been many years since I looked at that, and 
then only briefly).  I guess that constrains which debug formats can be used, 
but I don't know any details.

pdp11-elf was done as an experiment by someone else, in binutils.  I'll ask 
about the status of that.  If it's possible to deliver that, it would 
presumably enable DWARF support.  Is that all common code so it's a matter of 
enabling it, or would "DWARF machine details for pdp11" have to be defined?

        paul