There are C warnings for typecasting, RTTI, and other things. Fix these to get noise out of the build.
Added pull request for this fix at https://github.com/sgothel/gluegen/pull/20. I've tested it on Windows 8 and OS X 10.9.
Expanded the scope of this bug to removal of non-C warnings too, like the spurious warnings coming from gluegen about emission of unnamed structs and CL_ALIGN not being set. Changes for this bug are all going on https://github.com/WadeWalker/jocl/tree/bug_988_fix_build_warnings.