It already compiles on Linux without any modifications whatsoever:

  g++ -O2 -march=native -mtune=native -D__LINUX_PULSE__ -D__LINUX_ALSA__ -D__UNIX_JACK__ \
      lcc_rtaudio.cpp RtAudio.cpp -o lcc -pthread -ljack -lasound  -lpulse-simple -lpulse

The above will give you a binary with the Jack, ALSA and PulseAudio backends baked in.