Compiler error - fft_ifft_dit_1ch_graph.hpp

[nielsvanetten]

Hi all,

I get an error in the "fft_ifft_dit_1ch_graph.hpp" file when trying to compile it on a A72 cortex application in Vitis.

Error:
.../FFT/3_FFT_DSP/AI_FFT/src/fft_ifft_dit_1ch_graph.hpp:676: undefined reference to fft_4096_tmp2

Same for fft_2048_tmp2, fft_1024_tmp2 etc...

Since I don't get this error when compiling this on the AI-engine level, I believe that this is probably due to different versions of the C++ compiler.

It seems the C++ compiler for the cortex application doesnt recognize: alignas(32) extern cint32_t fft_4096_tmp2[FFT4096_SIZE]

[nielsvanetten]

[nielsvanetten]

think i found the bug:
https://stackoverflow.com/questions/10422034/when-to-use-extern-in-c

variable needs to be declared into the "fft_ifft_dit_1ch_graph.hpp" file

[nielsvanetten]

basically I think the best way to fix this is to just remove the extern and const parameters since these variables are not used in multiple source files, I will make a push request

[nielsvanetten]

see pull request, this solved my issue

[xflorentw]

Hi @nielsvanetten
I am not sure this is a right solution as this might affect the code on the AIE.
In my opinion, the DSPLib code should not be visible by the PS code. Thus I would recommend to add the following in the graph to hide the code inside the graph to the PL:
#if defined(AIESIM) || defined(X86SIM) || defined(ADF_FRONTEND)