We have a support case that shows GCC 7 sometimes creates
DW_TAG_label refering to itself via a DW_AT_abstract_origin
when using LTO. This for example triggers the sanity check
added below during LTO bootstrap.
Making this check cover more than just DW_AT_abstract_origin
breaks bootstrap on trunk for
/* GNU extension: Record what type our vtable lives in. */
if (TYPE_VFIELD (type))
{
tree vtype = DECL_FCONTEXT (TYPE_VFIELD (type));
gen_type_die (vtype, context_die);
add_AT_die_ref (type_die, DW_AT_containing_type,
lookup_type_die (vtype));
so the check is for now restricted to DW_AT_abstract_origin.
Bootstrapped on x86_64-unknown-linux-gnu, OK?
My workaround for the GCC 7 problem is
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 5590845d2a4..07185a1a0d3 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -23030,7 +23031,7 @@ gen_label_die (tree decl, dw_die_ref context_die)
lbl_die = new_die (DW_TAG_label, context_die, decl);
equate_decl_number_to_die (decl, lbl_die);
- if (origin != NULL)
+ if (origin != NULL && origin != decl)
add_abstract_origin_attribute (lbl_die, origin);
else
add_name_and_src_coords_attributes (lbl_die, decl);
that's not needed on trunk because there we dont' end up
with LABEL_DECLs with self-DECL_ABSTRACT_ORIGIN (and not DECL_ABSTRACT).
Thanks,
Richard.
* dwarf2out.cc (add_AT_die_ref): Assert we do not add
a self-ref DW_AT_abstract_origin.
---
gcc/dwarf2out.cc | 1 +
1 file changed, 1 insertion(+)
diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc
index 1e0cec66c5e..0070a9e8412 100644
--- a/gcc/dwarf2out.cc
+++ b/gcc/dwarf2out.cc
@@ -4908,6 +4908,7 @@ add_AT_die_ref (dw_die_ref die, enum dwarf_attribute
attr_kind, dw_die_ref targ_
{
dw_attr_node attr;
gcc_checking_assert (targ_die != NULL);
+ gcc_assert (targ_die != die || attr_kind != DW_AT_abstract_origin);
/* With LTO we can end up trying to reference something we didn't create
a DIE for. Avoid crashing later on a NULL referenced DIE. */
--
2.35.3
