I get the error : FunctionCompile::err1: Cannot resolve the “Complex” type constructor.
I did look briefly at compilation in v14.2, (which worked), but having upgraded to v14.3 now fails! I did not find anything about compiler setup etc. What am I missing?
Your code works fine for me with the same version ("14.3.0 for Mac OS X ARM (64-bit) (July 8, 2025)"). I have whatever out-of-the-box setup Mathematica provides for FunctionCompile (that is, I have not tweaked the setup in any way).
The fact that it works out-of-the-box for you guys made me realise that I had obviously over tweaked!
On closer examination of my setup, I had recently created a flat Association variable (which includes a ‘get’ Key) for some global Options. Although the ‘get’ was lower case, I had not wrapped it as a String. This was silently interfering with the FunctionCompile Command. Although interestingly not the Get command itself?
Resolved now. Note to self - ensure Options are STRINGS.