[MLton] Compiler warnings

[Jesper Louis Andersen]

I have thought about this for a week now and since I have not turned
it down, it might be yet another of those ''what if'' ideas to throw
to the table. 

GCC has a -Wall option for turning on a bunch of options all about
warnings. My current idea is something around mimicking -Wunused
which should report values defined in the code but never used in the
code. Maybe the dead-code eliminator can do this job neatly? 

I had hoped to find more things of debatable problems, but the rest
of the GCC warnings are tied to C being braindead. The unused variable
stuff could be nice to have though, since I have caught myself in
the process of doing ''manual'' elimination of those from my programs.

Any comments to this idea?

-- 
j.