Re: [Discuss-gnuradio] Trouble with latest GIT of Gnu Radio

[Marcus D. Leech]

On 07/05/2010 12:03 PM, Tom Rondeau wrote:
> On Sat, Jul 3, 2010 at 8:17 PM, Marcus D. Leech <address@hidden> wrote:
>   
>> Environment: 3 different computers, all running F12 with all latest updates
>> Both USRP2 and USRP1
>>
>> Latest GIT
>>
>> A segfault is provoked in gr_sync_decimator.cc:64    when you have an
>> FFT filter, and change its size
>>  at runtime.
>>
>> Doesn't matter which circbuf factory I'm using, or which of my 3 systems
>> (two are x86_64 and one is x86).
>>
>> Doesn't matter whether the FFT filter is "big" or little.  Increasing
>> one from 2 taps to 128 taps was enough
>>  to cause a segmentation fault.
>>
>> Doesn't seem to matter whether you're increasing the size, or decreasing it.
>>
>>
>> --
>> Marcus Leech
>> Principal Investigator
>> Shirleys Bay Radio Astronomy Consortium
>> http://www.sbrac.org
>>     
>
> Marcus,
>
> I can't seem to replicate this problem on my Ubuntu 10.04 64-bit machine.
>
> I created a signal, fft filter (ccc), and a file sink with a
> threshold, connected them, and ran the flow graph. To run it, I used
> this, where mytb is the top_block class.
>
> def main():
>     taps0 = gr.firdes.low_pass_2(1, 1, 0.1, 0.1, 60)
>     taps1 = gr.firdes.low_pass_2(1, 1, 0.01, 0.01, 60)
>
>     print "Setting start taps (ntaps = %d)" % (len(taps0))
>     tb = mytb(taps0)
>     tb.start()
>
>     time.sleep(0.5)
>
>     print "Setting new taps (ntaps = %d)" % (len(taps1))
>     tb.fftfilt.set_taps(taps1)
>
>     time.sleep(0.5)
>
>     tb.stop()
>     tb.wait()
>
>
> The initial taps have length 27 and the new taps (taps1) have length
> 273. I also tried it with both complex in/out/taps and float
> in/out/taps.
>
> Is there something else that I'm missing?
>
> Tom
>
>
>   
Well, on my 3 F12 systems, it reliably dumpeth the core for my
flowgraph.   I'll see if I can do a reduced
  version (like what you've done) to provoke the same issue.


-- 
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org