From 63e7c2c5289c5f4a4c13ed1d0b41822da1b2fc67 Mon Sep 17 00:00:00 2001
From: Timo Heister <timo.heister@gmail.com>
Date: Wed, 29 Aug 2012 21:27:03 +0000
Subject: [PATCH] return from ConstraintMatrix::close() in case of a cycle so
 we can test this.

git-svn-id: https://svn.dealii.org/trunk@26168 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/source/lac/constraint_matrix.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/deal.II/source/lac/constraint_matrix.cc b/deal.II/source/lac/constraint_matrix.cc
index dd99a2e504..abc67f6225 100644
--- a/deal.II/source/lac/constraint_matrix.cc
+++ b/deal.II/source/lac/constraint_matrix.cc
@@ -386,6 +386,8 @@ void ConstraintMatrix::close ()
                     // there are constraints or dofs in our system, we must have a cycle.
                     ++n_replacements;
                     Assert(n_replacements/2<largest_idx, ExcMessage("Cycle in constraints detected!"));
+                    if (n_replacements/2>=largest_idx)
+                      return; // this enables us to test for this Exception.
 #endif
                   }
                 else
-- 
2.39.5