From b78489625e949d54ef2c7b2f236576049e80a464 Mon Sep 17 00:00:00 2001
From: David Kastrup <dak@gnu.org>
Date: Tue, 10 Sep 2013 11:34:02 +0200
Subject: [PATCH] Avoid undefined behavior after "music expected" error

This problem was introduced in 2.17.4 by an oversight in issue 2862.
---
 lily/parser.yy | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lily/parser.yy b/lily/parser.yy
index b54191d839..fcde23ac9d 100644
--- a/lily/parser.yy
+++ b/lily/parser.yy
@@ -1063,7 +1063,10 @@ music_arg:
 	{
 	        $$ = make_music_from_simple (parser, @1, $1);
                 if (!unsmob_music ($$))
+		{
                         parser->parser_error (@1, _ ("music expected"));
+			$$ = MAKE_SYNTAX ("void-music", @$);
+		}
 	}
 	| composite_music %prec COMPOSITE
 	;
@@ -2472,7 +2475,10 @@ event_chord:
                                 unsmob_music ($$)->set_property ("articulations",
                                                                  scm_reverse_x ($2, SCM_EOL));
                         else
+			{
                                 parser->parser_error (@1, _("music expected"));
+				$$ = MAKE_SYNTAX ("void-music", @1);
+			}
 		}
 	}
 	| simple_chord_elements post_events	{
-- 
2.39.5