diff --git a/Doc/ext/newtypes.tex b/Doc/ext/newtypes.tex
index c0ec264..cd2c045 100644
--- a/Doc/ext/newtypes.tex
+++ b/Doc/ext/newtypes.tex
@@ -1039,7 +1039,7 @@
 
         cbresult = PyObject_CallObject(self->my_callback, NULL);
         if (cbresult == NULL)
-            PyErr_WriteUnraisable();
+            PyErr_WriteUnraisable(self->my_callback);
         else
             Py_DECREF(cbresult);