Fixes the assert problem caused by ledger line spanners.

This fix makes it such that ledger lines are not printed when
there is a no-line staff symbol.  This makes sense, as a note
cannot be above or below the staff if the staff does not exist,
which means that ledger lines should not be used.

diff --git a/lily/ledger-line-spanner.cc b/lily/ledger-line-spanner.cc
index 49ff7119116f85e45a027f3fab630edc7905b702..a518bc9225b5ef0abdd819cb42436c8336d6cda5 100644 (file)
--- a/lily/ledger-line-spanner.cc
+++ b/lily/ledger-line-spanner.cc
@@ -320,7 +320,7 @@ Ledger_line_spanner::print (SCM smob)
       Item *h = dynamic_cast<Item *> (heads[i]);
 
       int pos = Staff_symbol_referencer::get_rounded_position (h);
-      if (!staff_extent.contains (pos - sign (pos)))
+      if (!staff_extent.contains (pos - sign (pos)) && !staff_extent.is_empty ())
        {
          Interval head_size = h->extent (common[X_AXIS], X_AXIS);
          Interval ledger_size = head_size;