* class.c (build_vtable_entry_ref): Lose vtbl parm.  Fix for new abi.
        (build_vtbl_ref): Adjust.
        (dfs_accumulate_vtbl_inits): Set TREE_CONSTANT on the vtable address.
        * decl2.c (lang_f_options): Remove huge-objects, vtable-thunks.
        Re-add vtable-gc.
        (unsupported_options): Correspondingly.

        * decl2.c (maybe_make_one_only): Check flag_weak, not
        supports_one_only().

From-SVN: r42393