From 871c8e6c4c2993b0e33b51103a5dad783d743e13 Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Fri, 27 Oct 2017 07:50:05 -0600
Subject: [PATCH] Add an assertion to provide a nicer error message.

---
 source/dofs/dof_renumbering.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/source/dofs/dof_renumbering.cc b/source/dofs/dof_renumbering.cc
index 2788416f46..71faad5b40 100644
--- a/source/dofs/dof_renumbering.cc
+++ b/source/dofs/dof_renumbering.cc
@@ -1512,6 +1512,11 @@ namespace DoFRenumbering
    const Tensor<1,DoFHandlerType::space_dimension> &direction,
    const bool                                       dof_wise_renumbering)
   {
+    Assert ((dynamic_cast<const parallel::Triangulation<DoFHandlerType::dimension,DoFHandlerType::space_dimension>*>
+             (&dof.get_triangulation())
+             == nullptr),
+            ExcNotImplemented());
+
     if (dof_wise_renumbering == false)
       {
         std::vector<typename DoFHandlerType::active_cell_iterator> ordered_cells;
-- 
2.39.5