* 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().


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@42393 138bc75d-0d04-0410-961f-82ee72b054a4