diff --git a/Objects/complexobject.c b/Objects/complexobject.c
index c074aee..3c26b5b2 100644
--- a/Objects/complexobject.c
+++ b/Objects/complexobject.c
@@ -418,6 +418,11 @@
 {
         Py_complex div, mod;
 	PyObject *d, *m, *z;
+
+	if (PyErr_Warn(PyExc_DeprecationWarning,
+		       "complex divmod() and // are deprecated") < 0)
+		return NULL;
+
 	errno = 0;
 	div = c_quot(v->cval,w->cval); /* The raw divisor value. */
 	if (errno == EDOM) {