Re: [IDEA+RFC] Possible solution for min()/max() war

[Jamie Lokier <lk@tantalophile.demon.co.uk>]

Roman Zippel wrote:
> >    3. Warning added to GCC for signed vs. unsigned comparisons
> >       _regardless_ of type size.  This would also catch erroneous
> >       unsigned char vs. EOF checks in misuses of stdio.
> 
> Do you know of such bug in the context of min()?

I don't know of an actual example.  This one is made up:

       min (int, len, big_size)

Now if big_size has unsigned type, and does not fit in the range of int,
this expression will return the value of big_size cast to int, i.e. a
negative value.  The suggested warning would catch this potential bug.

I don't know if it would warn for too many other things.  Certainly, a
sizeof() exception (don't warn about signed comparison with sizeof()
result) is essential; perhaps too many other exceptions are required
too.

-- Jamie