--- libev/ev_iouring.c.orig	2020-03-08 16:55:17.000000000 +0100
+++ libev/ev_iouring.c	2021-04-21 17:34:58.985032376 +0200
@@ -297,6 +297,7 @@
   ++EV_SQ_VAR (tail);
   /*ECB_MEMORY_FENCE_RELEASE; /* for the time being we assume this is not needed */
   ++iouring_to_submit;
+  return NULL;
 }
 
 /*****************************************************************************/
@@ -328,6 +329,7 @@
       ev_ref (EV_A);
       ev_io_stop (EV_A_ &iouring_tfd_w);
     }
+  return 0;
 }
 
 ecb_cold