diff --git a/dune/stuff/common/string_internal.hh b/dune/stuff/common/string_internal.hh
index 6b6a1871dfa17b85629e75f62a75f2bf1e9e00ee..689944dd2b9b0b10529f8661f32f6e77b5bded3d 100644
--- a/dune/stuff/common/string_internal.hh
+++ b/dune/stuff/common/string_internal.hh
@@ -338,7 +338,7 @@ static inline typename std::enable_if<!is_vector<T>::value && !is_matrix<T>::val
 to_string(const T& ss, const std::size_t precision)
 {
   std::ostringstream out;
-  out << std::setprecision(precision) << ss;
+  out << std::setprecision(boost::numeric_cast<int>(precision)) << ss;
   return out.str();
 }