diff -Nur a/tests/regression/client/client.c b/tests/regression/client/client.c
--- a/tests/regression/client/client.c	2015-12-25 17:39:45.000000000 +0000
+++ b/tests/regression/client/client.c	2022-03-29 19:33:18.646398117 +0100
@@ -27,6 +27,7 @@
 #include <syscall.h>
 #include <sys/epoll.h>
 #include <sys/types.h>
+#include <sys/socket.h>
 #include <sys/un.h>
 #include <unistd.h>