[Bug debug/94450] lto abstract variable emitted as concrete decl

["vries at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94450

--- Comment #10 from Tom de Vries <vries at gcc dot gnu.org> ---
(In reply to rguenther@suse.de from comment #9)
> On Fri, 3 Apr 2020, vries at gcc dot gnu.org wrote:
> 
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94450
> > 
> > --- Comment #8 from Tom de Vries <vries at gcc dot gnu.org> ---
> > (In reply to Richard Biener from comment #7)
> > > The DW_TAG_imported_unit are now gone for GCC 10.  So can we consider this
> > > fixed?
> > 
> > I'd like a PR to refer to at the to-be-added xfail in the gdb test-case (and
> > the PR should be open as long as that test fails with trunk gcc). It doesn't
> > matter for me whether that's this particular PR or a follow-up PR.
> 
> OK, so if you have a (single?) specific testcase that's still affected
> please duplicate that into a new bugzilla.  It's always better to
> have something specific to track.
> 
> So did the patch not change anything?

Well, the changes I asked for related to the example in comment 0 are:
- drop the import
- change the tag from DW_TAG_compile_unit to DW_TAG_partial unit.

AFAIU the patch only removes the import, so in that sense I do not consider the
test-case reported in comment 0 addressed.

I have not tried out the patch.  FWIW, I did try a quick dwarf-assembly
experiment (not the ada one, which will cost more time I expect, but modified
gdb testsuite test-case gdb.dwarf2/imported-unit.exp) and confirmed that
neither only removing the import nor only changing the tag is sufficient to get
only one entry in the symtab.

Anyway, I understand the example is somewhat abstract, and I'll file the actual
ada example.