Re: Buffer overflow Article - CACM

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Mon, 14 Nov 2005 08:09:04 +0100, Pascal Obry wrote:

>> Then they say that bounds checking adds 100% overhead. This may be true
>> of trying to patch C, but it's certainly not true of all the checks Ada
>> does, which is much more than simply bounds checking. In practice I have
>> never found a case in which leaving checks in was too slow, nor where
>> turning them off saved more than 10%.
> 
> And then even if there was 100% overhead, what the problem ? For most
> applications this is not critical and at least for debugging the
> application this is invaluable. Running with a 100% overhead is
> equivalent to running with a computer 18 months old. Not that bad :)
> Again I understand that in some domains we are counting the CPU cycles,
> but this is not the majority of applications.

This is not the whole truth. I agree that overhead caused by run-time
checks is not a big deal. But that is not the problem in my view. Let they
be 0%! The real problem is that a check may fail while program crash is not
an option. This means that there must be some error handling. More errors
may happen at run-time more complex infrastructure one would require. Add
here unit tests for these errors etc.

It is a design problem and design problems are in order of magnitude more
expensive than any hardware.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de