In C your compiler can help you with conversions and if not, please use a better one. In this regard, C is a very pragmatic language, and hence for actual work it is a more "serious" programming language than programming languages which are based on some idealistic theory that pedantic typing will fix all your problems, but actually keep you from doing your job.
Warnings are just noise, so there's no point in printing them--they will be ignored (maybe not when there is a singular warning, but if warnings are allowed to accumulate beyond some manageable threshold). If a warning is worth printing, it should be treated as an error, and if you treat it as an error, you now are "strict" by definition.
