Re: [Lilypond-auto] Issue 2831 in lilypond: Crash with slurs and flags and duration-override

[lilypond]

Comment #1 on issue 2831 by address@hidden: Crash with slurs and flags  
and duration-override
http://code.google.com/p/lilypond/issues/detail?id=2831

A cursory glance reveals this to be a difficult problem.

In current master, the backtrace to the crash is:


#0  0x0823d6a2 in Pointer_group_interface::count (me=0x85d7680,  
sym=0xb616a900)
    at /home/mikesol/lilypond-git/lily/pointer-group-interface.cc:28
#1  0x082d3b4f in Stem::head_count (me=0x85d7680)
    at /home/mikesol/lilypond-git/lily/stem.cc:183
#2  0x082d40c3 in Stem::is_normal_stem (me=0x85d7680)
    at /home/mikesol/lilypond-git/lily/stem.cc:286
#3  0x082d4038 in Stem::is_invisible (me=0x85d7680)
    at /home/mikesol/lilypond-git/lily/stem.cc:280
#4  0x08299946 in Slur_score_state::enumerate_attachments (this=0xbfffa9e8,
    end_ys=...) at /home/mikesol/lilypond-git/lily/slur-scoring.cc:682
#5  0x08297407 in Slur_score_state::fill (this=0xbfffa9e8, me=0x85d8d70)
    at /home/mikesol/lilypond-git/lily/slur-scoring.cc:307
#6  0x08297a63 in Slur::calc_control_points (smob=0xb7df9548)
    at /home/mikesol/lilypond-git/lily/slur-scoring.cc:337

I then rewrote the beginning of is_normal_stem as:


  extract_grob_set (me, "note-heads", heads);
  if (!heads.size ())
    return false;

Which also hangs, this time as:


#0  0x006f5340 in ?? () from /lib/tls/i686/cmov/libc.so.6
#1  0x006f5e2f in mcount () from /lib/tls/i686/cmov/libc.so.6
#2  0x0833fa24 in is_unpure_pure_container (s=0xb7defc40)
    at /home/mikesol/lilypond-git/lily/unpure-pure-container.cc:28
#3  0x0814ca2c in Grob::internal_get_object (this=0x86c4590, sym=0xb616a900)
    at /home/mikesol/lilypond-git/lily/grob-property.cc:295
#4  0x0823d2a7 in internal_extract_grob_array (elt=0x86c4590,
    symbol=0xb616a900)
    at /home/mikesol/lilypond-git/lily/pointer-group-interface.cc:100
#5  0x082cebdb in Stem::is_normal_stem (me=0x86c4590)
    at /home/mikesol/lilypond-git/lily/stem.cc:287
#6  0x082ceb09 in Stem::is_invisible (me=0x86c4590)
    at /home/mikesol/lilypond-git/lily/stem.cc:280
#7  0x0829e33a in Slur_score_state::enumerate_attachments (this=0xbfffa9e8,
    end_ys=...) at /home/mikesol/lilypond-git/lily/slur-scoring.cc:682
#8  0x0829bdfb in Slur_score_state::fill (this=0xbfffa9e8, me=0x85d90d0)
    at /home/mikesol/lilypond-git/lily/slur-scoring.cc:307

So there's something maybe wrong with the way the grob array is stored in  
memory?