* typeck2.c (add_exception_specifier): Only pedwarn for an
        incomplete type.
        (require_complete_eh_spec_types): New fn.
        (cxx_incomplete_type_diagnostic): Also support pedwarning.
        * typeck.c (complete_type_or_diagnostic): Likewise.
        * call.c (build_call): Call require_complete_eh_spec_types.
        * rtti.c (get_pseudo_ti_desc): Give an error rather than aborting
        on an incomplete type.

From-SVN: r56822