[myhdl-list] Re: MyHDL / ModelSim cosim

[Jan D. <ja...@ja...>]

Jan Decaluwe wrote:

> 
> My guess is that it is a memory leak caused by the myhdl PLI code, not
> by the simulator. This means that I should be able to reproduce it with
> Icarus.
> 
> I have briefly looked at the code and I can see potential memory leaks:
> 
> - apparently call back handles should be explicitly freed with a special
> vpi call after registering;
> - at a certain point the code malloc's memory in a callback which is
> never freed.
> 
> As callbacks are created all the time during simulation, this could
> explain it. I will run a check with Icarus to see if I can
> reproduce/resolve the issue.

I did some experiments - please disregard the above, it is
probably all wrong. Both with cver and Icarus I see a
memory leak, but my hypotheses above are not correct:

- freeing the callback handles explicitly doesn't work in Icarus
and makes no difference in cver. At this point I also don't
see why it should actually make a difference
- the malloc'ed memory is free'd automatically, so the
simulation crashes on an explicit attempt to free it.

I'm searching for another explanation.

Jan

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