[Bug debug/46123] [4.5/4.6 Regression] ICE: in output_aranges, at dwarf2out.c:11531 with -feliminate-dwarf2-dups -g

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46123

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-18 13:13:57 UTC ---
Created attachment 22446
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22446
gcc46-pr46123.patch

Ugh, this is very ugly.  gen_subprogram_die sometimes decides to reuse old_die
which was DW_AT_declaration and can be deeply nested in type children, which
breaks -feliminate-dwarf2-dups as well as -gdwarf-4 if those are moved to
separate CUs (either the comdat ones or .debug_types).
The patch fixes this by not reusing the old die if doing one or another way of
duplicate removals (perhaps could do an extra check if the old_die is actually
in a tree that is going to be moved, which wouldn't be that hard to do for
break_out_includes, but would be uglier for .debug_types).  Or we could do it
always.  Unfortunately just doing that leads to crashes, because context_die is
NULL and dwarf2out_finish doesn't want to see limbo DIEs with type contexts, so
the patch also uses comp_unit_die () in that case.

Jason/Cary, what do you think?