These are the packages that would be merged, in order:

Calculating dependencies ...

!!! Problem resolving dependencies for =media-sound/denemo-2.6.0-r102
 done!
Dependency resolution took 0.82 s (backtrack: 0/20).


!!! The ebuild selected to satisfy "=media-sound/denemo-2.6.0-r102" has unmet requirements.
- media-sound/denemo-2.6.0-r102::gentoo USE="X alsa aubio nls portaudio portmidi rubberband -debug -gtk-doc -jack -test" GUILE_SINGLE_TARGET="-2-2"

  The following REQUIRED_USE flag constraints are unsatisfied:
    guile_single_target_2-2

  The above constraints are a subset of the following complete expression:
    exactly-one-of ( guile_single_target_2-2 )