I've recently had some trouble with C++'s implicit casting, so I'm looking for a way to warn people if somebody attempts to assign an int32_t to a uint64_t or whatever.  BOOST_STATIC_ASSERT would work wonders for this, except that the code base I'm working with is quite large and relies on a lot of implicit casting, so immediately breaking everything with assertions is unrealistic.

It looks like BOOST_STATIC_WARNING (http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/static_warning.html) would be ideal for me, however, I cannot get it to actually emit a warning.  I have attached a quick example of what I am looking for, but it essentially boils down to this not doing anything:

My compiler is g++ 4.4.3 with --std=c++0x -Wall -Wextra.

Thanks!