Index: Python/_warnings.c
===================================================================
--- Python/_warnings.c	(revision 73839)
+++ Python/_warnings.c	(working copy)
@@ -317,6 +317,8 @@
     }
     if (rc == 1) {
         text = PyObject_Str(message);
+        if (text == NULL)
+            goto cleanup;
         category = (PyObject*)message->ob_type;
     }
     else {