--- mpqc-2.3.1/src/lib/chemistry/qc/mbptr12/transform_tbint.h.cpp11	2005-07-12 07:52:34.000000000 +0900
+++ mpqc-2.3.1/src/lib/chemistry/qc/mbptr12/transform_tbint.h	2016-04-24 18:02:54.275499008 +0900
@@ -61,7 +61,13 @@ class TwoBodyMOIntsTransform : virtual p
 protected:
   /** By default, integrals smaller than zero_integral are considered zero.
       This constant is only used in checking integrals, not computing them. */
-  static const double zero_integral = 1.0e-12;
+  static 
+#if __cplusplus >= 201103L
+  constexpr
+#else
+  const
+#endif 
+  double zero_integral = 1.0e-12;
   /// Predefined enumerated type for the MO spaces
   typedef struct {
     enum {Space1, Space2, Space3, Space4};