diff --git a/tests/mapper.c b/tests/mapper.c
index 1006a8c4..6edce711 100644
--- a/tests/mapper.c
+++ b/tests/mapper.c
@@ -36,6 +36,10 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 
 #include <sys/mman.h>
 
+#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
+# define MAP_ANONYMOUS MAP_ANON
+#endif
+
 int
 main (int argc, char **argv)
 {