On Thu, 16 Nov 2023, Jason Merrill wrote: > On 10/30/23 08:57, Richard Biener wrote: > > 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? > > Let's also check for DW_AT_specification, since that's the other one get_AT > follows. OK with that change.
The following is what I applied. Richard. >From 2c070d92beea9e46947693c623b44551dc18e513 Mon Sep 17 00:00:00 2001 From: Richard Biener <rguent...@suse.de> Date: Mon, 30 Oct 2023 13:17:11 +0100 Subject: [PATCH] Assert we don't create recursive DW_AT_{abstract_origin,specification} To: gcc-patches@gcc.gnu.org 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 and DW_AT_specification both of which we follow within get_AT. * dwarf2out.cc (add_AT_die_ref): Assert we do not add a self-ref DW_AT_abstract_origin or DW_AT_specification. --- gcc/dwarf2out.cc | 3 +++ 1 file changed, 3 insertions(+) diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc index 9850d094707..d187be9b786 100644 --- a/gcc/dwarf2out.cc +++ b/gcc/dwarf2out.cc @@ -4908,6 +4908,9 @@ 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 + && attr_kind != DW_AT_specification)); /* 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