Use MPI_COMM_WORLD as communicator if a NULL pointer was passed for the cGH

argument into PUGH's overloadable for CCTK_Barrier().
This allows CCTK_Barrier() to be called even before a grid hierarchy exists
(eg. during PARAM_CHECK).


git-svn-id: http://svn.cactuscode.org/arrangements/CactusPUGH/PUGH/trunk@488 b61c5cb5-eaca-4651-9a7a-d64986f99364

1 files changed, 2 insertions, 1 deletions

diff --git a/src/Comm.c b/src/Comm.c
index fdcde7c..68e8fa7 100644
--- a/src/Comm.c
+++ b/src/Comm.c
@@ -510,7 +510,8 @@ int PUGH_DisableGArrayGroupComm(pGH *pughGH, int first_var, pComm *groupcomm)
 int PUGH_Barrier(const cGH *GH)
 {
 #ifdef CCTK_MPI
-  CACTUS_MPI_ERROR (MPI_Barrier (PUGH_pGH (GH)->PUGH_COMM_WORLD));
+  CACTUS_MPI_ERROR (MPI_Barrier (GH ? PUGH_pGH (GH)->PUGH_COMM_WORLD :
+                                      MPI_COMM_WORLD));
 #else
   GH = GH;
 #endif