\version "2.8.0"

top = \relative c''
{
	\repeat unfold 3 { g,,32 g'' g g g,32 g' g g g,32 g' g g g,32 g' g g g,32 g' g g g,32 g' g g}	
}

pedal = \relative c'
{
	g,2. | g | g |
}

bottom = \relative c'
{
	\repeat unfold 3 { s8 g g g g g | }
}

dynamics = \relative { s2.\p }
fingering = \relative { s2.^\markup "fingering" }
barring = \relative
{	
	\override TextSpanner #'edge-text = #'("start" . "end")
	\override TextSpanner #'padding = #6
	
	s2.\startTextSpan | s2. | \break s2 s8 s16 s32 s\stopTextSpan |
	
}


<<
\context Staff = guitar
{	
	\clef "G_8"
	\time 3/4
	
	#(override-auto-beam-setting '(end * * * *) 1 4 'Staff)
	#(override-auto-beam-setting '(end * * * *) 1 2 'Staff)
	#(override-auto-beam-setting '(end * * * *) 3 4 'Staff)
	
	\override Staff.NoteCollision #'merge-differently-headed = ##t
	\override Staff.NoteCollision #'merge-differently-dotted = ##t
	
	<<
		\context Voice = "1" { \voiceOne \top }
		%%%remove the line below, and the textspanner works correctly
		\context Voice = "2" { \voiceTwo \pedal }
		\context Voice = "4" { \voiceFour \bottom }
		\context Voice = "3" { \voiceThree << \dynamics \\ << \fingering \\ \barring >> >> }
	>>
}
>>