diff --git a/dd.c b/dd.c
index 5dbcf9a..1e6a3a8 100644
--- a/dd.c
+++ b/dd.c
@@ -74,6 +74,10 @@
 
 #include "dd.h"
 
+#ifndef LLONG_MAX
+#define LLONG_MAX (0x7fffffffffffffffLL)
+#endif
+
 #define NO_CONV
 
 //#include "extern.h"