=== modified file 'src/ChangeLog'
--- src/ChangeLog	2014-05-06 21:13:37 +0000
+++ src/ChangeLog	2014-05-07 08:54:40 +0000
@@ -1,3 +1,8 @@
+2014-05-07  Jarek Czekalski  <jarekczek@poczta.onet.pl>
+
+	Fix initialization of minibuffer history variable (Bug#xxxxx).
+	* minibuf.c (read_minibuf): Initialize histval to Qnil if unbound.
+
 2014-05-06  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* image.c: Do not use libpng if HAVE_NS, as NS does its own thing.

=== modified file 'src/minibuf.c'
--- src/minibuf.c	2014-03-21 17:04:50 +0000
+++ src/minibuf.c	2014-05-07 08:54:21 +0000
@@ -708,8 +708,10 @@
       /* If variable is unbound, make it nil.  */
 
       histval = find_symbol_value (Vminibuffer_history_variable);
-      if (EQ (histval, Qunbound))
-	Fset (Vminibuffer_history_variable, Qnil);
+      if (EQ (histval, Qunbound)) {
+        Fset (Vminibuffer_history_variable, Qnil);
+        histval = Qnil;
+      }
 
       /* The value of the history variable must be a cons or nil.  Other
 	 values are unacceptable.  We silently ignore these values.  */