2.11.15: superfluous warnings, converting to pdf fails on ubuntu edgy

[Tuukka Verho]

Every time a slur and a DynamicLineSpanner begin from the same note, a
following warning is printed:

----

GNU LilyPond 2.11.15
Processing `testi.ly'
Parsing...
Interpreting music... 
testi.ly:5:11: warning: Ignoring grob for slur: DynamicLineSpanner.
avoid-slur not set?
        c4(
           \< c c c)\!
[1]
Preprocessing graphical objects...
Layout output to `testi.ps'...

-----

minimal test code:

\relative c' {  
        c4(\< c c c)\!
}

Also, converting to pdf fails for any input file (I'm running ubuntu
edgy and my gs version is "ESP Ghostscript 815.02"):

-------

Converting to `testi.pdf'...
`gs -q  -dSAFER  -dDEVICEWIDTHPOINTS=595.28 -dDEVICEHEIGHTPOINTS=841.89
-dCompatibilityLevel=1.4  -dNOPAUSE -dBATCH -r1200  -sDEVICE=pdfwrite
-sOutputFile="testi.pdf" -c .setpdfwrite -f "testi.ps"' failed (256)
/home/tuukka/lily-dev/lilypond/usr/bin/../share/lilypond/current/ly/init.ly:37:1:
 error: GUILE signaled an error for the expression beginning here
#
 (if (or (pair? toplevel-scores) output-empty-score-list)
/home/tuukka/lily-dev/lilypond/usr/bin/../share/lilypond/current/ly/init.ly:37:5:
 error: syntax error, unexpected '(', expecting '='
#(if 
     (or (pair? toplevel-scores) output-empty-score-list)
programming error: Parsed object should be dead: static
scm_unused_struct* Prob::mark_smob(scm_unused_struct*)
continuing, cross fingers
programming error: Parsed object should be dead: static
scm_unused_struct* Context_def::mark_smob(scm_unused_struct*)
continuing, cross fingers
programming error: Parsed object should be dead: static
scm_unused_struct* Grob::mark_smob(scm_unused_struct*)
continuing, cross fingers
error: failed files: "testi.ly"

------

thanks,
Tuukka