When traditional Bards died, their harps (or fiddles) were broken and/or hung from weeping willow trees as a sign of mourning and respect. The instruments would be left to slowly fall apart in the weather, NEVER to be played by another person. There was considered to be a spiritual connection between player and instrument, and the instruments were treated as entities in their own right. So the song is telling us that the musician is going to die. This was originally sung as a dirge, not a rollicking drinking song.