c/9072: -Wconversion should be split into two distinct flags

[Segher Boessenkool]

Zack Weinberg wrote:
> 
> I'm very much in favor of making -Wconversion more useful, but is
> there any reason not to shift the argument-type-conversion warnings
> entirely over to -Wtraditional?  Particularly if the warning is
> avoided for prototypes in system headers (so that 'sinf' and the like
> raise no complaints) -- this would, for instance, catch the occasional
> problem we have with arguments of type 'bool' in GCC itself.
> 
> Then -Wconversion would be entirely for dubious type conversions on
> assignment.

This is the intended behaviour of my patch, modulo in my opinion passing
a "too wide" argument to a function is a dubious assignment, too.


Segher