Garbage collector memory leak "feature"?

[Steven Schveighoffer]

"0ffh" wrote
> Steven Schveighoffer wrote:
>> "0ffh" wrote
>> But why should the GC have to worry about pointers in random data?  My 
>> question is, is there a *need* for the GC to assume any data could be a 
>> pointer, does any code actually *depend* on that behavior?  I really 
>> would like to see an example of where it is necessary.
>
> Well, we are not just talking about random data, but of data which is
> excplicitly defined as "data of random type, including pointers".
> It is a feature, not a bug; and not incidentally, but planned this way.

OK, I understand it is planned this way.  I even understand the rationale 
behind it.  But this is more of a "functions as designed" feature than a 
real feature.  I'm sure the writer of the GC did not intend for this side 
effect to occur.

I think we are way off track here.  There is a problem with the garbage 
collector in that it can assume data that is not a pointer is a pointer, and 
therefore not collect the data pointed to when it should.  It may be that 
not scanning void[] is not the solution to the problem, but there is 
definitely a problem.

Maybe the solution is for data to have the type information instead of the 
pointer type containing the type information.  What I mean is, even though 
it is a void *, it points to some data.  If the type of that data is stored 
with the data, then you can tell if the pointed-to data has pointers in it, 
regardless of the fact that the type is void.

Maybe there is another solution.

All I know is that if it's going to leak memory for no good reason that I 
can see, then I don't want to use it in a production-quality product, 
because not only is it impossible to tell whether it will leak data (note 
that this problem is completely non-deterministic), but it is impossible to 
FIX the problem without significantly paranoid code.  And oh by the way I 
need to see all the source code to all libraries I use so that I don't 
accidentally use something that contains a void *.

-Steve