Wrong barlines in second alternative after "repeat volta" when repeat starts with upstep

[Walter Gull]

I refer to the third example in section "6.7.2 Repeat syntax" in the current
LilyPond documentation:
http://lilypond.org/doc/v2.11/Documentation/user/lilypond/Repeat-syntax

This example starts with an upstep. In the fourth repetition the three "g"
quarter notes are not to be played. The note PLAYED immediately before the first
note ("a") under the "quarta volta" hood is the half note "f", which is played
during beats 3 and 4. Thus that first "a" has to be played on beat 1, and the
bar under the "quarta volta" hood is an ordinary full 4/4 bar, NOT an isolated
upstep. As a consequence the next barline should only appear between the
second-last and the last "a" note.

I modified your example using "unfold" instead of "volta" (a modification that
should only change the typesetting, but not the playing of the music) and get a
correct rendering.

See http://gull.homeunix.org/Documentation/ly-bug-repeat/

r1      literally your example snippet
r2      modification with "unfold"

r1.pdf is wrong
r2.pdf is correct (although maybe musically not too sensible ...)
P.S.: Sorry for typesetting the examples an an octave lower, but that is here
irrelevant.

Besides: Thank you for the great software you wrote!