avoid breaking replay, handle MPI_OP_NULL case

diff --git a/src/smpi/smpi_mpi_dt.c b/src/smpi/smpi_mpi_dt.c
index bc03ee9..0db4d81 100644 (file)
--- a/src/smpi/smpi_mpi_dt.c
+++ b/src/smpi/smpi_mpi_dt.c
@@ -1460,7 +1460,7 @@ MPI_Op smpi_op_new(MPI_User_function * function, int commute)
 
 int smpi_op_is_commute(MPI_Op op)
 {
 
 int smpi_op_is_commute(MPI_Op op)
 {

-  return op-> is_commute;
+  return (op==MPI_OP_NULL) ? 1 : op-> is_commute;

 }
 
 void smpi_op_destroy(MPI_Op op)
 }
 
 void smpi_op_destroy(MPI_Op op)