Thread 1
  synfig::Mutex::lock (this=0x9103330) at mutex.cpp:121
  Lock (this=0xbfcbfa9c, x=@0x9103330) at /home/chris/programs/synfig/git/synfig-core/trunk/src/synfig/mutex.h:53
  synfig::ValueNode_Duplicate::operator() (this=0x9103248, t={value_ = 0}) at valuenode_duplicate.cpp:194
  synfig::ValueNode_Composite::operator() (this=0x91057b8, t={value_ = 0}) at valuenode_composite.cpp:121
  synfig::Context::set_time (this=0xbfcbfe0c, time={value_ = 0}) at context.cpp:310
  synfig::Canvas::set_time (this=0x9104430, t={value_ = 0}) at canvas.cpp:276
  synfig::Layer_PasteCanvas::set_time (this=0x9104050, context={...}, time={value_ = 0}) at layer_pastecanvas.cpp:251
  synfig::Context::set_time (this=0xbfcc001c, time={value_ = 0}) at context.cpp:314
  synfig::Canvas::set_time (this=0x9102ae0, t={value_ = 0}) at canvas.cpp:276
  studio::CanvasView::rebuild_ducks (this=0x9114818) at canvasview.cpp:2770
  sigc::bound_mem_functor0<void, studio::CanvasView>::operator() (this=0x924b608) at /usr/include/sigc++-2.0/sigc++/functors/mem_fun.h:1787

Thread 2
  synfig::RWLock::writer_lock (this=0x9108494) at mutex.cpp:204
  WriterLock (this=0xb0c5d7f8, x=@0x9108494) at mutex.h:98
  synfig::Context::set_time (this=0xb0c5d924, time={value_ = 1}) at context.cpp:300
  synfig::Layer_Duplicate::accelerated_render () at layer_duplicate.cpp:188
  synfig::Context::accelerated_render () at context.cpp:258
  synfig::Layer_PasteCanvas::accelerated_render () at layer_pastecanvas.cpp:386
  synfig::Context::accelerated_render () at context.cpp:258
  synfig::Target_Tile::render_frame_ () at target_tile.cpp:250
  synfig::Target_Tile::render (this=0x92be0c8, cb=0x0) at target_tile.cpp:382
  studio::AsyncRenderer::render_target (this=0x8b501b8) at asyncrenderer.cpp:495
  sigc::bound_mem_functor0<void, studio::AsyncRenderer>::operator() (this=0x9166124) at /usr/include/sigc++-2.0/sigc++/functors/mem_fun.h:1787