opImplicitCast/opImplicitCastFrom

[Christopher Wright]

Andrei Alexandrescu wrote:
> Jarrett Billingsley wrote:
>> On Tue, Oct 28, 2008 at 7:21 AM, bearophile <bearophileHUGS at lycos.com> 
>> wrote:
>>> This document from experience says that integral overflow bugs are a 
>>> significant percentage of the total:
>>> http://www.st.cs.uni-sb.de/edu/seminare/2005/advanced-fp/docs/sweeny.pdf
>>
>> No, it says array-out-of-bounds errors, dereferencing null pointers,
>> accessing uninitialized variables _and_ integer overflows together
>> represent 50% of the bugs.  I don't know about you but I run into
>> those first three cases (well.. two, since there aren't uninitialized
>> variables in D) waaaaay more than I do integer overflows.
> 
> I think the frequency of a bug should be multiplied with the trouble it 
> takes to fix it. Frequency alone isn't terribly relevant.
> 
> Andrei

And the time it takes to find the source of the bug. It doesn't matter 
if it's a one-character fix if you have to go through 10 KLOC to find 
where the problem is.

For dereferencing null, you can look at the call stack and add contracts 
to find where null's being passed in. For integer overflows, it's a bit 
more difficult.