From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Sun, 16 Oct 2016 16:08:55 +0000 (+0200)
Subject: ensure allocation of an even number of elements
X-Git-Tag: v8.5.0-rc1~561^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6557bdd83c6bb1ff8581155b7ac66358322ed2c4;p=dealii.git

ensure allocation of an even number of elements
---

diff --git a/include/deal.II/lac/vector_operations_internal.h b/include/deal.II/lac/vector_operations_internal.h
index 593256c0eb..54167ff4d6 100644
--- a/include/deal.II/lac/vector_operations_internal.h
+++ b/include/deal.II/lac/vector_operations_internal.h
@@ -1146,7 +1146,9 @@ namespace internal
 
       if (n_chunks > threshold_array_allocate)
         {
-          large_array.resize(n_chunks);
+          // make sure we allocate an even number of elements,
+          // access to the new last element is needed in do_sum()
+          large_array.resize(2*((n_chunks+1)/2));
           array_ptr = &large_array[0];
         }
       else