Some empty "" chords may be causing trouble with Jenkins. Jenkins builds are stalling when generating PDFs for some morris tunes. I suspect the problem may be an empty chord "" and abc2abc's attempt to transpose it. I've been meaning to remove the chords from the horn output, because abc2abc transposes them too, which renders them not terribly useful. So get on and do it. Also remove "" from the morris tunes where it occurs.

X: 1
T:Haste To The Wedding
% Nottingham Music Database
S:EF
M:6/8
K:D
P:A
F/2G/2|"D"A2A A2f|"G"ede fdB|"D"A2A AGF|"Em"GFG "A7"EFG|
"D"A2A A2f|"G"ede fdB|"D"A2A "A7"a2g|"D"fdd d2:|
P:B
d/2e/2|"D"fga "B7" agf | "Em" gab "A7" bag |"D" fga "B7" agf|
"G"gfg "A7"efg|"D"a3 "Bm"f3|"G"ede fdB|"D"A2A "A7"a2g|"D"fdd d2:|