anchor.diff:  , opusfile
   , portaudio
   , portmidi
  -, protobuf
  +, protobuf-cpp
   , qt5
   , rubberband
   , soundtouch
  
positive.code:     opusfile
      portaudio
      portmidi
      protobuf
      qt5.qtbase
      qt5.qtscript
      qt5.qtsvg
      qt5.qttranslations
      qt5.qtxmlpatterns
      rubberband
      soundtouch
      sqlite
  
negative.code:   sconsFlags = [
      "build=release"
      "qt5=1"
      "qtdir=${qt5}"
  
      "opengles=0"
      "hss1394=0"
  