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test/boostmultiprec.cpp

@@ -72,6 +72,7 @@ namespace Eigen {
   template<>
   Real test_precision<Real>() { return 1e-50; }
 
+  // needed in C++93 mode where number does not support explicit cast.
   namespace internal {
     template<typename NewType>
     struct cast_impl<Real,NewType>