I've filed a new issue at
http://code.google.com/p/v8/issues/detail?id=358

I don't have access to any memory checker on windows but I'm able to
reproduce the crash scenario in the debugger. If there's anything else I can
do to help just ask.

2009/5/27 Mikhail Naganov <[email protected]>

> Actually, what we saw in our continuous build was an assertion failure
> due to missing tick samples (and the following crash of the test was
> intended to capture the stack of the failure). This is the problem I
> targeted in this fix.
>
> What you're talking about is a really strange thing. TickSample's
> 'samples' array isn't dynamic. And in their own turn, TickSamples are
> stored in a static array (you can find it in class Profiler from
> log.cc). So a crash you describing can be caused either by a wild
> TickSample pointer passed to TickEvent function or by a corrupted
> TickSample object. Personally, I haven't encountered anything of this
> kind so far. Can you try to involve any memory checking tools in your
> investigation?
>
> On Wed, May 27, 2009 at 00:30, Tobias Käs <[email protected]>
> wrote:
> > Thanks for the explanation, this sounds reasonable if the source of the
> > crash are missing profiler samples. For clarity can you explain what
> crash
> > you are actually getting? I've tried to reproduce this on a windows debug
> > build and I'm getting irregular crashes unrelated to the actual loop
> timing
> > of the test. My crashes are in log.cc#1096 (Logger::TickEvent) - the
> > embedded stack vector seems to point to invalid memory.
> >
> > Sorry for the noise if this is unrelated.
> >
> >
> > 2009/5/26 Mikhail Naganov <[email protected]>
> >>
> >> Tobias, running short (less than a second) profiling sessions is
> >> impractical. This test ensures that sampler is running and its results
> >> are retrieved, no more. The problem is that sampler is implemented
> >> either as a signal handler or as a separate thread. I can have no
> >> guarantees from OS in what period of time it will be spawned and will
> >> start to work. So in the test I'm trying to achieve a balance between
> >> making the test to pass in a timely manner and maintaining stability.
> >>
> >> The perfect solution would be to establish explicit synchronization
> >> between the sampler and the test, but adding facilities to code only
> >> to be used in tests doesn't seem to be practical.
> >>
> >> On Tue, May 26, 2009 at 22:46,  <[email protected]> wrote:
> >> > The fix looks to me like it's just hiding the problem, not fixing it.
> >> > The crashes may be caused by an edge case which gets triggered if the
> >> > time span is short.
> >> >
> >> > http://codereview.chromium.org/115772
> >> >
> >
> >
>

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