Re: [Valgrind-users] Memcheck and lost pointer tracking

[Nicholas N. <n.n...@gm...>]

On Fri, May 8, 2009 at 3:06 PM, Theodoros V. Kalamatianos
<th...@gm...> wrote:
>>
>> In general, what you are proposing is possible, but it's not easy, is
>> really slow and would be lots of extra code in Memcheck.
>
> What if it was done in two passes? Run memcheck normally, and then re-run
> valgrind repeatedly in order to track a specific memory leak each time. You
> could say e.g. --tool=analyse-leak --with-alloc=foo.c:111 and have valgrind
> track those pointers only. Could we exploit that to make things easier
> speed-wise and coding-wise?

Two passes introduces problems of its own -- it's great if you have a
totally deterministic program, otherwise you're in trouble.  Or you
can use deterministic replay techniques but that's more complication.

> IMO when you _know_ you have a problem, a slower but effective valgrind is
> definitely acceptable.

Of course.  My broader point is that there's an enormous difference
between proposing something and implementing it, especially when the
proposal is ambitious.

Nick