https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80913
--- Comment #1 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
My money's on:
Stat hack representation
* name-lookup.c (STAT_HACK_P, STAT_TYPE, STAT_DECL,
MAYBE_STAT_DECL, MAYBE_STAT_TYPE): New.
(stat_hack): New.
(find_namespace_binding): Replace with ...
(find_namespace_slot): ... this.
(find_namespace_value): New.
(name_lookup::search_namespace_only,
name_lookup::adl_namespace_only): Adjust.
(update_binding): Add SLOT parameter, adjust.
(check_local_shadow): Use find_namespace_value.
(set_local_extern_decl_linkage): Likewise.
(do_pushdecl): Adjust for namespace slot.
(push_local_binding): Assert not a namespace binding.
(check_for_out_of_scope_variable): Use find_namespace_value.
(set_identifier_type_value_with_scope): Likewise.
(get_namespace_binding): Likewise.
(set_namespace_binding): Delete.
(set_global_binding): Directly update the binding.
(finish_namespace_using_decl): Likewise.
(lookup_type_scope_1): Use find_namespace_slot and update.
(do_push_nested_namespace): Use find_namespace_value.
But x86_64-linux is not being affected in the way you describe. The backtrace
is something borking in the spelling correcting stuff.
