diff --git a/src/OpenMesh/Core/Geometry/Vector11T.hh b/src/OpenMesh/Core/Geometry/Vector11T.hh
index b8382bd6..785d85bd 100644
--- a/src/OpenMesh/Core/Geometry/Vector11T.hh
+++ b/src/OpenMesh/Core/Geometry/Vector11T.hh
@@ -107,7 +107,7 @@ class VectorT {
             return DIM;
         }
 
-        static const size_t size_ = DIM;
+        static constexpr const size_t size_ = DIM;
 
         //-------------------------------------------------------------- constructors