[Bug c++/68208] g++ doesn't warn against reference self-initialization

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68208

--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
Patch posted for review here:
https://gcc.gnu.org/ml/gcc-patches/2015-11/msg01420.html