[Bug c++/55203] No unused warning for variables of non-trivial types

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55203

--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Doc patch posted to https://gcc.gnu.org/ml/gcc-patches/2016-02/msg01184.html