Include includes.h for compat bits.
diff --git a/regress/unittests/conversion/tests.c b/regress/unittests/conversion/tests.c
index ebb48a1..6dd77ef 100644
--- a/regress/unittests/conversion/tests.c
+++ b/regress/unittests/conversion/tests.c
@@ -5,6 +5,8 @@
  * Placed in the public domain
  */
 
+#include "includes.h"
+
 #include <sys/types.h>
 #include <sys/param.h>
 #include <stdio.h>