diff --git a/Objects/setobject.c b/Objects/setobject.c
index 0041a10..ed3d190 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -1958,7 +1958,7 @@
 	return result;
 }
 
-int
+Py_ssize_t
 PySet_Size(PyObject *anyset)
 {
 	if (!PyAnySet_Check(anyset)) {