From: Denis Davydov <davydden@gmail.com>
Date: Mon, 19 Mar 2018 14:10:51 +0000 (+0100)
Subject: check that size of ArrayView in internal::all_reduce() is the same across the given... 
X-Git-Tag: v9.0.0-rc1~303^2~1
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c3adda46fa269b5ee0b0ae744e425b7192f9dec4;p=dealii.git

check that size of ArrayView in internal::all_reduce() is the same across the given communicator
---

diff --git a/include/deal.II/base/mpi.templates.h b/include/deal.II/base/mpi.templates.h
index 8302d7cdc9..09473cf03d 100644
--- a/include/deal.II/base/mpi.templates.h
+++ b/include/deal.II/base/mpi.templates.h
@@ -120,6 +120,21 @@ namespace Utilities
 #ifdef DEAL_II_WITH_MPI
         if (job_supports_mpi())
           {
+#ifdef DEBUG
+            {
+              const unsigned int rank = this_mpi_process(mpi_communicator);
+              const int size = values.size();
+              int size_min = 0;
+              int size_max = 0;
+              int ierr2 = 0;
+              ierr2 = MPI_Reduce(&size, &size_min, 1, MPI_INT, MPI_MIN, 0, mpi_communicator);
+              AssertThrowMPI(ierr2);
+              ierr2 = MPI_Reduce(&size, &size_max, 1, MPI_INT, MPI_MAX, 0, mpi_communicator);
+              AssertThrowMPI(ierr2);
+              if (rank==0)
+                Assert (size_min == size_max, ExcMessage("values has different size across MPI processes."));
+            }
+#endif
             const int ierr = MPI_Allreduce
                              (values != output
                               ?