diff --git a/src/mesh/CellType.hpp b/src/mesh/CellType.hpp
index 5864210068349ffddf18b458a0df991112efa21c..d3aa4578f769972e06f9df976df16c53737af80f 100644
--- a/src/mesh/CellType.hpp
+++ b/src/mesh/CellType.hpp
@@ -28,6 +28,7 @@ std::string_view name(const CellType& cell_type)
     case CellType::Pyramid: return "pyramid";
     case CellType::Prism: return "prism";
     case CellType::Hexahedron: return "hexahedron";
+    default: return "unknown cell type";
   }
 }