diff --git a/io/tst-posix_fallocate.c b/io/tst-posix_fallocate.c
index 35c6489fde..53f0704c34 100644
--- a/io/tst-posix_fallocate.c
+++ b/io/tst-posix_fallocate.c
@@ -1,3 +1,4 @@
+#include <fcntl.h>
 #include <sys/stat.h>
 
 static void do_prepare (void);