Package: libstdc++6-4.1-dev
Version: 4.1.2-6
In Line 246ff, it says:
explicit
codecvt(state_type& __enc, size_t __refs = 0)
: __codecvt_abstract_base<intern_type, extern_type,
state_type>(__refs)
{ }
Using -Wall, one gets an "unused parameter" warning for __enc.
One solution would be to remove the __enc, and just leave the type.
(However I don't know where the encoding information is passed to then...)