[Bug bootstrap/41404] expr.c undefined reference while linking jc1

["davek at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #9 from davek at gcc dot gnu dot org  2009-09-19 10:56 -------
(In reply to comment #8)
> The "ret" string is shared between some attribute and a value from
> CONST_STRING.

  Sorry, as I just figured out I was off by one on that:

(gdb) fin
Run till exit from #0  gen_label_for_indirect_string (node=0x7e945910)
    at /gnu/gcc/gcc-unpatched/gcc/dwarf2out.c:6849
get_debug_string_label (str=0x7f15e0b8 "ret")
    at /gnu/gcc/gcc-unpatched/gcc/dwarf2out.c:6864
6864      return gen_rtx_SYMBOL_REF (Pmode, node->label);
(gdb) print ((struct indirect_string_node *) 0x7e945910)[0]
$5 = {str = 0x7ff2f498 "ret", refcount = 2, form = 0,
  label = 0x8284dc0 "*LASF74"}
(gdb)

> But prune_unused_types_walk_attribs resets the count to 0:
>       /* Set the string's refcount to 0 so that prune_unused_types_mark
>          accounts properly for it.  */
>       if (AT_class (a) == dw_val_class_str)
>         a->dw_attr_val.v.val_str->refcount = 0;
> and while attributes are walked, location lists are not and thus nothing
> notices it is still used.  I'll have to read the prune_unused_types stuff
> carefully to understand how this can be fixed, ideally if we could just
> decrement refcount in prune_unused_types_walk_attribs, as long as we are sure
> it is walked for all attributes, it could fix this.  Alternatively we'd have to
> walk all location lists as well, looking for labels for strings.

  But we're looking at the same suspect here anyway :)


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41404