diff --git a/src/core/osmo_io.c b/src/core/osmo_io.c
index bcd4add..8b53aa6 100644
--- a/src/core/osmo_io.c
+++ b/src/core/osmo_io.c
@@ -787,8 +787,8 @@
 
 	iofd->pending = NULL;
 
-	if (osmo_iofd_ops.close)
-		rc = osmo_iofd_ops.close(iofd);
+	OSMO_ASSERT(osmo_iofd_ops.close);
+	rc = osmo_iofd_ops.close(iofd);
 	iofd->fd = -1;
 	return rc;
 }