From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Wed, 16 May 2018 23:48:26 +0000 (+0200)
Subject: Use Utilities::MPI::create_group instead of MPI_Comm_create
X-Git-Tag: v9.1.0-rc1~1127^2~1
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2bf722914fbdff144480dd90db6c930759f8103b;p=dealii.git

Use Utilities::MPI::create_group instead of MPI_Comm_create
---

diff --git a/source/base/process_grid.cc b/source/base/process_grid.cc
index 9f04655539..f75596fe17 100644
--- a/source/base/process_grid.cc
+++ b/source/base/process_grid.cc
@@ -170,9 +170,8 @@ namespace Utilities
 
       // Create the communicator based on the group
       // Note that on most cores the communicator will be MPI_COMM_NULL.
-      // FIXME: switch to MPI_Comm_create_group for MPI-3 so that only processes within the to-be subgroup call this
-      ierr = MPI_Comm_create(mpi_communicator, inactive_with_root_group,
-                             &mpi_communicator_inactive_with_root);
+      ierr = Utilities::MPI::create_group(mpi_communicator, inactive_with_root_group,
+                                          55, &mpi_communicator_inactive_with_root);
       AssertThrowMPI(ierr);
 
       ierr = MPI_Group_free(&all_group);