diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index c56ef9f..163976e 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -3202,6 +3202,7 @@
 	/* wrong return value */
 	PyErr_SetString(PyExc_TypeError,
 	      "character mapping must return integer, None or unicode");
+	Py_DECREF(x);
 	return -1;
     }
 }