diff --git a/app/common/rational.h b/app/common/rational.h
index 951cc7305..4f3fcf27d 100644
--- a/app/common/rational.h
+++ b/app/common/rational.h
@@ -129,4 +129,7 @@ private:
   intType gcd(intType &x, intType &y);
 };
 
+#define RATIONAL_MIN rational(LONG_MIN, 1)
+#define RATIONAL_MAX rational(LONG_MAX, 1)
+
 #endif // RATIONAL_H