release: 1.3.53

[lilypond.git] / lily / spanner.cc

diff --git a/lily/spanner.cc b/lily/spanner.cc
index d3623668e1cd876893dbe7ffacd15ce285b40e5f..c384224889c36aa47e621ca2d3c2db55ef11c84e 100644 (file)
--- a/lily/spanner.cc
+++ b/lily/spanner.cc
@@ -25,6 +25,9 @@ Spanner::do_break_processing ()
   //break_into_pieces
   Item * left = spanned_drul_[LEFT];
   Item * right = spanned_drul_[RIGHT];
+
+  if (!left || !right)
+    return;
   
   if  (left == right)
     {
@@ -92,14 +95,17 @@ Spanner::do_break_processing ()
          Direction d = LEFT;
          do
            {
-             Item *&pc_l = bounds[d] ;
-             if (!pc_l->line_l())
-               pc_l =  pc_l->find_prebroken_piece(- d);
-         
-             assert (pc_l);
+             if (!bounds[d]->line_l())
+               bounds[d] = bounds[d]->find_prebroken_piece(- d);
            }
          while ((flip(&d))!= LEFT);
 
+         if (!bounds[LEFT] ||  ! bounds[RIGHT])
+           {
+             programming_error ("bounds of this piece aren't breakable. ");
+             continue; 
+           }
+
          Spanner *span_p = dynamic_cast<Spanner*>(clone ());
          span_p->set_bound(LEFT,bounds[LEFT]);
          span_p->set_bound(RIGHT,bounds[RIGHT]);
@@ -159,8 +165,8 @@ Spanner::set_bound(Direction d, Item*i)
     }
 
   /**
-     Prevent the column -> line_of_score -> column -> line_of_score -> etc situation
-  */
+     We check for Line_of_score to prevent the column -> line_of_score
+     -> column -> line_of_score -> etc situation */
   if (d== LEFT && !dynamic_cast<Line_of_score*> (this))
     {
       set_parent (i, X_AXIS);