diff --git a/regress/unittests/conversion/tests.c b/regress/unittests/conversion/tests.c
index eaa96bb25..ebb48a14d 100644
--- a/regress/unittests/conversion/tests.c
+++ b/regress/unittests/conversion/tests.c
@@ -8,7 +8,9 @@
 #include <sys/types.h>
 #include <sys/param.h>
 #include <stdio.h>
+#ifdef HAVE_STDINT_H
 #include <stdint.h>
+#endif
 #include <stdlib.h>
 #include <string.h>