try to fix petsc FETools::interpolation_difference

git-svn-id: https://svn.dealii.org/trunk@28693 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/source/fe/fe_tools.cc b/deal.II/source/fe/fe_tools.cc
index 26ed3a42fa02dd22feb85a5f149ee4766192e3c9..dd0e3dd74c78f93fa392e9e65be82eb2fec3ef62 100644 (file)
--- a/deal.II/source/fe/fe_tools.cc
+++ b/deal.II/source/fe/fe_tools.cc
@@ -1671,10 +1671,13 @@ namespace FETools
             DoFTools::extract_locally_relevant_dofs (dof2,
                                                      dof2_locally_relevant_dofs);
 
+            PETScWrappers::MPI::Vector  u2_out (dynamic_cast<const PETScWrappers::MPI::Vector *> (&u1)->get_mpi_communicator(),
+                dof2_locally_owned_dofs);
+            interpolate(dof1, u1, dof2, constraints2, u2_out);
             PETScWrappers::MPI::Vector  u2 (dynamic_cast<const PETScWrappers::MPI::Vector *> (&u1)->get_mpi_communicator(),
                                             dof2_locally_owned_dofs,
                                             dof2_locally_relevant_dofs);
-            interpolate(dof1, u1, dof2, constraints2, u2);
+            u2 = u2_out;
             interpolate(dof2, u2, dof1, constraints1, u1_interpolated);
           }
         else