It's an opt-in warning that some people like to use. It was introduced
to clang 3.0.0 in 2011 by
98766db785
However, the feature is intentionally used here and the generated code is legit.
Make both sides happy.
Change-Id: I79335cd3a6a6cc128fa65f77d201a12f67424260
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>