[mpich-devel] MPI_Reduce_scatter_block() with zero-size, NULL buffers.

[Lisandro Dalcin]

This is from a build of master updated today and configured with
--enable-g=all. AFAICT, previous versions of MPICH did not generate
this error. Was this an intentional change?

Traceback (most recent call last):
  File "/home/dalcinl/Devel/mpi4py-dev/test/test_msgzero.py", line 36,
in testReductions
    comm.Reduce_scatter_block(self.null_b, self.null_b)
  File "Comm.pyx", line 714, in mpi4py.MPI.Comm.Reduce_scatter_block
(src/mpi4py.MPI.c:93219)
Exception: Invalid buffer pointer, error stack:
PMPI_Reduce_scatter_block(1182): MPI_Reduce_scatter_block(sbuf=(nil),
rbuf=(nil), recvcount=0, MPI_INT, MPI_SUM, MPI_COMM_SELF) failed
PMPI_Reduce_scatter_block(1142): Buffers must not be aliased


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Lisandro Dalcin
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