Re: Adaptation of Federico La Roccas ISDB-T blocks for DVB-T

[Ralf Gorholt]

Hi Vasil,

thank you for your message. As I have no experience with GNU Radio and
command line debugging, your hints may be really helpful. I have
attached the gdb and valgrind output to this email.

In the gdb output thread 27 that receives the SIGSEGV is the DVB-T
"Symbol Inner Interleaver" that comes with GNU Radio, not one of my blocks.

As far as valgrind is concerned, it tells me for my block OFDM
Synchronization: "Conditional jump or move depends on uninitialised
value(s)". I will see if I can find out which variable is uninitialized
and how I can get rid of this problem.

Kind regards,

Ralf

Am 10.12.2021 um 12:35 schrieb Vasil Velichkov:
> Hi Ralf,
>
> On 10/12/2021 11.52, Ralf Gorholt wrote:
> > Unfortunately, when I deactivate the original flowgraph, it does no
> > longer work and I get a -11 return code.
> The "-11" value means that you got a segmentation fault and the process was 
> kill with signal 11 (SIGSEGV)
>
> https://docs.python.org/3.8/library/subprocess.html#subprocess.CalledProcessError.returncode
> https://www.man7.org/linux/man-pages/man7/signal.7.html
>
> In my opinion the easiest way to debug segfaults is to run the flowgraph under 
> gdb and valgrind. Open your flowgraph in the gnuradio-companion and then 
> Generate (F5) but do not Execute (F6). The open a terminal, go where the 
> flowgraph python (.py) file was generated and execute
>
>   gdb -ex run --args /usr/bin/python3 test.py
>
> and then when it stops execute `bt` command in the gdb's shell and provide the 
> full output. To run it under valgrind execute
>
>   valgrind --tool=memcheck /usr/bin/python3 test.py
>
> Adjust the path to your python interpreter and its version if needed.
>
> Regards,
> Vasil

gdb_output.txt
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valgrind_output.txt
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