Re: [Discuss-gnuradio] crashes, memory errors and valgrind

[Patrick Strasser]

Tom Rondeau wrote on 2012-06-04 14:18:
> On Sun, Jun 3, 2012 at 2:22 PM, Patrick Strasser
> <address@hidden> wrote:
>> Hi Tom,
>>
>> Tom Rondeau wrote on 2012-06-03 17:12:
>>> On Sat, Jun 2, 2012 at 5:50 AM, Patrick Strasser
>>> Patrick,
>>>
>>> It looks like you're problem is in the rational_resampler code. I
>>> wonder if there's something about the resampling rate being used
>>> that's causing something to go out of bounds here. Can you dig into
>>> the code and figure out what interpolation and decimation rates are
>>> being used?
>>
>> Interpolation is 1, decimation is 2.

>> Full valgrind log in
>> http://pastebin.com/7GCs3bWy
> 
> I was hoping you'd say the interpolation and/or decimation were some
> ridiculously large numbers. Since the block is only actually
> decimating, could you replace it in the code with an fir_filter_fff
> (or fft_filter_fff) just for testing purposes? That'll help us see if
> it's the rational resampler itself or something more general.

What seems strange to me is the allocation of a buffer of a non by 8
dividable size, that is accessed in blocks of 8 bytes. So the last read
always either does not touch the end of the buffer, or it reads beyond
the end.

I'm a little sparse at time until Sunday evening. I tried to write some
mini program starting from dial_tone.cc which uses a filter, have to
convince cmake to compile it... learning ;-)

Regards

Patrick
-- 
Engineers motto: cheap, good, fast: choose any two
Patrick Strasser <patrick dot strasser at  tugraz dot at>
Student of Telematics, Graz Univ. of Technology, Austria