Segmentation fault with \revert Stem #'(details beamed-lengths) in \voiceOne

[Rodolfo Zitellini]

Dear list,
Compiling the following snippet

notes = \relative c' {
        \clef treble \key c \major \time 2/4
        s16 [g s g ] s16 [g s g ] |
        s16 [g s g ] \override Stem #'(details beamed-lengths) = #'(15 15)
s16 [g s g ] |
        s16 [g s g ] s16 [g s g ] |
        s16 [g s g ] \revert Stem #'details #'beamed-lengths s16 [g s g ] |
        s16 [g s g ] s16 [g s g ] |
        }
        
\score {
        <<
        \new Staff {\voiceOne \notes }
        >>
}

I get a  segmentation fault (bus error). I am using MacOS X 10.5.8
x86. Tried it with lilypond 2.12.1, 2.13.11, 2.13.18. It seems that
the problem is generated by the \voiceOne (or \voiveTwo for the
matter) - removing that it compiles fine. It compiles file even if I
remove the \revert.
During some tests I noted that if I force the stems up or down in the
same snippet I get a SIGSEGV. I can generate a complete backtrace if
someone is interested.

BTW I am not fully sure I'm doing the right thing with beamed-lengths
(I want to lengthen the beams): the manual just says "List of stem
lengths given beam multiplicity", and I interpreted it as a list of
the maximum stem lengths beamed together. Am a wrong?

Thanks,
Rodolfo