Index: Src/hist.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/hist.c,v
retrieving revision 1.84
diff -u -r1.84 hist.c
--- Src/hist.c	18 Sep 2008 09:42:45 -0000	1.84
+++ Src/hist.c	20 Sep 2008 15:11:32 -0000
@@ -945,7 +945,7 @@
 mod_export Histent
 up_histent(Histent he)
 {
-    return he->up == hist_ring? NULL : he->up;
+    return !he || he->up == hist_ring? NULL : he->up;
 }
 
 /**/