From: David Kastrup <dak@gnu.org>
Date: Sat, 24 Oct 2015 11:18:50 +0000 (+0200)
Subject: Fix GC catastrophe in Slur_proto_engraver::derived_mark
X-Git-Tag: release/2.19.30-1~5^2
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=b9422b927e1d00b114f2028d86a9b59a5cbf54ed;p=lilypond.git

Fix GC catastrophe in Slur_proto_engraver::derived_mark

In Slur_proto_engraver::Event_info, note_ will be 0 for slurs not
attached to particular note events.  Calling self_scm on it is likely
to be a fatal error.
---

diff --git a/lily/slur-proto-engraver.cc b/lily/slur-proto-engraver.cc
index 5accd2c073..99e8e8ebfc 100644
--- a/lily/slur-proto-engraver.cc
+++ b/lily/slur-proto-engraver.cc
@@ -38,12 +38,14 @@ Slur_proto_engraver::derived_mark () const
   for (vsize i = start_events_.size (); i--;)
     {
       scm_gc_mark (start_events_[i].slur_->self_scm ());
-      scm_gc_mark (start_events_[i].note_->self_scm ());
+      if (start_events_[i].note_)
+        scm_gc_mark (start_events_[i].note_->self_scm ());
     }
   for (vsize i = stop_events_.size (); i--;)
     {
       scm_gc_mark (stop_events_[i].slur_->self_scm ());
-      scm_gc_mark (stop_events_[i].note_->self_scm ());
+      if (stop_events_[i].note_)
+        scm_gc_mark (stop_events_[i].note_->self_scm ());
     }
 }