diff -r 627ebd001708 Lib/test/test_array.py
--- a/Lib/test/test_array.py	Sun Feb 17 16:56:28 2013 +0200
+++ b/Lib/test/test_array.py	Mon Feb 18 02:30:20 2013 +0100
@@ -1069,6 +1069,10 @@
 
         self.assertRaises(TypeError, a.fromunicode)
 
+    def test_issue17223(self):
+        # this used to crash
+        self.assertRaises(ValueError, str, array.array('u', b'asdf'))
+
 class NumberTest(BaseTest):
 
     def test_extslice(self):
diff -r 627ebd001708 Modules/arraymodule.c
--- a/Modules/arraymodule.c	Sun Feb 17 16:56:28 2013 +0200
+++ b/Modules/arraymodule.c	Mon Feb 18 02:30:20 2013 +0100
@@ -2177,6 +2177,9 @@
     } else {
         v = array_tolist(a, NULL);
     }
+    if (v == NULL) {
+        return NULL;
+    }
 
     s = PyUnicode_FromFormat("array('%c', %R)", (int)typecode, v);
     Py_DECREF(v);