* cp-tree.h (flag_new_abi): Move.
(flag_use_cxa_atexit): Likewise.
(flag_honor_std): Likewise.
(flag_rtti): Likewise.
(vbase_offsets_in_vtable_p): Define.
(vptrs_present_everywhere_p): Likewise.
(TYPE_CONTAINS_VPTR_P): Likewise.
(dfs_walk_real): Declare.
* class.c (build_vbase_pointer_fields): Check
vbase_offsets_in_vtable_p.
(dfs_build_vbase_offset_vtbl_entries): Record the vbase indices in
BINFO_VPTR_FIELD.
(build_vbase_offset_vtbl_entries): Simplify.
(build_vbase_offset_vtbl_entries): Adjust.
(build_vbase_pointer): Add ability to look up vbase offsets in
vtable.
(start_vtable): New function.
(add_virtual_function): Use it.
(determine_primary_base): Use TYPE_CONTAINS_VPTR_P.
(num_extra_vtbl_entries): Use vbase_offsets_in_vtable_p.
(build_vtbl_initializer): Take the type of the complete object as
input. Use it to correctly calculate vbase offsets.
(dfs_finish_vtbls): Pass the complete type to
build_vtbl_initializer.
(check_bases_and_members): Use TYPE_CONTAINS_VPTR_P.
(create_vtable_ptr): Create a vtable even if there are no
new virtual functions, under the new ABI.
(finish_struct_1): Likewise.
(get_vfield_name): Use TYPE_CONTAINS_VPTR_P.
* decl.c (exapnd_static_init): Remove call to
preserve_initializer.
* decl2.c (mark_vtable_entries): Tweak to handle vbase offsets in
vtables.
* init.c (initialize_vtbl_ptrs): Initialize them in pre-order.
(expand_virtual_init): Use vbase_offsets_in_vtable_p.
(construct_virtual_bases): Don't initialize virtual base pointers
under the new ABI.
(build_aggr_init): Clean up comment.
(expand_aggr_init_1): Likewise.
* rtti.c (expand_class_desc): Store the virtual function table
index where the vbase offset lives in the offset field.
* search.c (dfs_walk_real): Make it global.
(dfs_debug_mark): Use TYPE_CONTAINS_VPTR_P.
* tree.c (make_binfo): Don't clear BINFO_VPTR_FIELD.
* tinfo.h (USItype): Make it signed under the new ABI.
* tinfo.cc (convert_to_base): New function. Encapsulate base
conversion logic here.
(__class_type_info::do_upcast): Use it.
(__class_type_info::do_dyncast): Likewise.
(__class_type_info::do_find_public_subobj): Likewise.