Still no spacing wishes found

[Erik Sandberg]

Hi,

This warning has been around for a long while, and I still don't understand 
what it means:
"warning: No spacing wishes found. Does your score have a staff?"
It occurs on scores which look perfectly valid to me, and I can never spot 
anything strange in the output.

I'm using lily 2.1.5, and one example of where it occurs is in
regression/lyric-combine.ly.

thanks,
Erik