diff --git a/tool/ytab.sed b/tool/ytab.sed
index ba7566ac7f..95a9b3e1eb 100755
--- a/tool/ytab.sed
+++ b/tool/ytab.sed
@@ -14,6 +14,7 @@ a\
 }
 /^yydestruct.*yymsg/,/{/{
   /^yydestruct/{
+    /,$/N
     /[, *]p)/!{
       H
       s/^/ruby_parser_&/