Ubuntu Aaarch64 18.04 ./configure error
checking for cos in -lm... yes
./configure: line 13500: syntax error near unexpected token FFT,' ./configure: line 13500:
PKG_CHECK_MODULES(FFT, fftw3f)'
Tried installing all the fftw packages -dev also
Going to switch for debian and give it a go as you can tell apart from simple compiling I am lost.
Posted here also seems both Ubuntu & Debian tried 18.04 & 20.04 64 bit https://github.com/xiph/speexdsp/issues/31#issuecomment-633379070