diff --git a/configure.ac b/configure.ac
index 1ce7e52..0ffce14 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,7 +1,7 @@
 AC_PREREQ(2.50)
 AC_INIT([libnfs], [1.9.8], [ronniesahlberg@gmail.com])
 AC_CONFIG_HEADERS([config.h])
-AM_INIT_AUTOMAKE([-Wall foreign])
+AM_INIT_AUTOMAKE([-Wall foreign subdir-objects])
 AC_CANONICAL_HOST
 AC_CONFIG_MACRO_DIR([m4])
 m4_pattern_allow([AM_PROG_AR])