communications: do not use MPI_REQUEST_NULL as sentinel value #73
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On some MPI implementaiotns (i.e., MPICH), the function MPI_Ibarrier can return a MPI_REQUEST_NULL if the communicator size is 1. Thus, it is not possible to use MPI_REQUEST_NULL as a sentinel value. A separate boolean is introduced to track if the local exchange has completed.
marcocisternino
approved these changes
Jun 30, 2020
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On some MPI implementaiotns (i.e., MPICH), the function MPI_Ibarrier can return a MPI_REQUEST_NULL if the communicator size is 1. Thus, it is not possible to use MPI_REQUEST_NULL as a sentinel value.
A separate boolean is introduced to track if the local exchange has completed.