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

[Roman Zippel]

Hi,

Linus Torvalds wrote:

> The problem with signed compares is not just comparing a signed entity
> against a unsigned one. It's quite common to have signed quantities on
> both sides, but _intending_ a unsigned comparison or vice versa.

Then it's a bug that should _not_ be fixed in the min macro. Unsigned
values should be hold in unsigned variables. If it's that common, please
show me a sane and realistic example.

> This is simply an area where it's better to make people think about the
> types, than to magically try to do the "right" thing.
> 
> > What's wrong with this version?
> 
> [ Standard stupid min() removed ]

It's not stupid, it does the right thing for the majority of the cases.
A cast just hides the problem. If you need a broken min macro to get
people thinking, you have a much bigger problem.

> You just fixed the "re-use arguments" bug - which is a bug, but doesn't
> address the fact that most of the min/max bugs are due to the programmer
> _indending_ a unsigned compare because he didn't even think about the
> type.

You maybe fixed a few bugs, but this new macro will only cause new
problems in the future. If we change only a single type, you have to
scan all min/max users if they possibly need to be changed too. Thanks
to the cast, the compiler won't even remotely help you finding them.

bye, Roman