Hello @nickg,
while elaborating Verilog fft core, I encountered strange error, I attach the project, so you can replicate easily.
cd nvc_elab
nvc --std=08 -H8192m -M8192m --messages=compact -a --relaxed bimpy.v bitreverse.v butterfly.v convround.v fftstage.v hwbfly.v laststage.v longbimpy.v qtrstage.v windowfn.v fftmain.v
nvc --std=08 -H8192m -M8192m --messages=compact -e fftmain
butterfly.v:159:23: fatal: cannot calculate longest static prefix
nvc_elab.zip
Michael