Re: Problem migrating an OOT module that uses FFT from 3.8 to 3.9

[Ralf Gorholt]

Hello Ron,

thank you very much.

I have walked right into the trap a second time :-( I should attach a
Post-It to my monitor screen to remind me that I might need to adapt the
CMakeLists.txt files when I change something...

Long story short, it works now :-)

Regards,

Ralf

Am 29.01.2022 um 23:54 schrieb Ron Economos:
> Ralf,
>
> Yes, I  was thinking about how I had done things in my 3.8 OOT's where
> I had used this syntax instead:
>
> fft::fft_complex *ofdm_fft;
>
> and
>
> ofdm_fft = new fft::fft_complex(ofdm_fft_size, false, 1);
>
> The other thing to check is the linking. Like so.
>
> https://github.com/drmpeg/gr-paint/blob/master/CMakeLists.txt#L78
>
> and
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/CMakeLists.txt#L25
>
> Ron
>
> On 1/29/22 14:24, Ralf Gorholt wrote:
> > Hello Ron,
> >
> > d_fft_calculator is (and was in the 3.8 version) an object and not a
> > pointer. That's why I already use the . and not the ->
> >
> > Regards,
> >
> > Ralf
> >
> > Am 29.01.2022 um 21:35 schrieb Ron Economos:
> > > Ralf,
> > >
> > > I'm not sure if you've done this already, but when you use
> > > d_fft_calculator, you need to change from -> to . to access it.
> > >
> > > Ron
> > >
> > > On 1/29/22 12:24, Ralf Gorholt wrote:
> > > > Hello all,
> > > >
> > > > I am currently trying to migrate an OOT module that uses an FFT object
> > > > internally from  GNU Radio version 3.8 to 3.9.
> > > >
> > > > In my .h file I have got this:
> > > >
> > > >     //old: gr::fft::fft_complex d_fft_calculator;
> > > >     gr::fft::fft_complex_fwd d_fft_calculator;
> > > >
> > > > and in the constructor member initializer list this:
> > > >
> > > >       //old: d_fft_calculator(gr::fft::fft_complex(pow(2.0, 10 +
> > > > mode),
> > > > true, 1)),
> > > >       d_fft_calculator(pow(2.0, 10 + mode), 1),
> > > >
> > > > The module compiles without a problem but when I start the flowgraph I
> > > > get the message "ImportError:
> > > > /usr/local/lib/libgnuradio-dl5eu.so.1.0.0:
> > > > undefined symbol: _ZN2gr3fft3fftISt7complexIfELb1EED1Ev". It looks
> > > > to me
> > > > that somewhere "fft_complex" is still called behind the scenes but I
> > > > can't see where.
> > > >
> > > > Can anyone tell me how I need to correct this?
> > > >
> > > > FYI, I have recreated the module and the blocks with gr_modtool and
> > > > then
> > > > copied the relevant code from the old to the new version.
> > > >
> > > > Thank you very much and kind regards,
> > > >
> > > > Ralf