The x86 version of Fldigi for macOS doesn't run on an Apple Silicon Mac. It's the first thing I've run in to that didn't work in emulation. Prompted by a tweet from @xssfox, who had done a native build but run into sound problems, I have also been able to build.
I see this in standard out:
||PaMacCore (AUHAL)|| AUHAL component not found.||PaMacCore (AUHAL)|| OpenStream @ 8000 returned: -9999: Unanticipated host error
Here's how I got it to build
Xcode is installed. Homebrew is installed.
brew install automake
brew install libsamplerate
brew install portaudio
brew install fltk
brew install libsndfile # I already had this
brew install hamlet
brew install xmlrpc-c
brew install pkg-config
brew install zlib
brew install lzlib
brew install libpng
brew install --build-from-source portaudio libsamplerate hamlib libpng fftw
# get the source code whichever way you prefer
./src/fldigi # to run!
It looks like this is an issue with PortAudio on macOS 11 when built against the macOS 11 SDK. "PA/CoreAudio uses some "deprecated" APIs which fail on Mac OS 11.0 #218".
This issue in PortAudio that deals with the issue.