Collision between acciaccatura and time signature

[Mick Killick]

Hi,

Please see the comment lines in the following, very short file for an 
explanation of the bug.

\version "2.12.0"

\paper{ ragged-right=##t }

upper = \relative c' {

        \clef treble
        \key c \major
        \time 12/8

        % The next line, obviously, works as expected.

%       g'1.

        % But, replace it with this - \acciaccatura fis8 g1. - and the 
acciaccatura's slur will be interrupted with an extra time signatre,

        % and the bass staff will add an additional treble cleff and time 
signature at the beginning of the line.

        \acciaccatura fis8 g1.
}

lower = \relative c' {

        \clef bass
        \key c \major
        \time 12/8

        c,1.
}

\score {

        \new PianoStaff <<

                \set PianoStaff.instrumentName = #"Piano"
                \new Staff = "upper" \upper
                \new Staff = "lower" \lower
        >>

        \layout { }
        \midi { }
}

I do hope I've understood the code correctly and that I'm not wasting your time.

Best regards,

Mick Killick