https://gitweb.dealii.org/ - dealii.git/commit

author	Wolfgang Bangerth <bangerth@colostate.edu>
	Sun, 9 Jan 2022 18:03:16 +0000 (11:03 -0700)
committer	Wolfgang Bangerth <bangerth@colostate.edu>
	Sun, 9 Jan 2022 18:09:31 +0000 (11:09 -0700)
commit	b3b2b973adcc15259e32f932a583a9fed09b2195
tree	88bfaa6eb4c9f5b1edf3ac5fbd98f84ae97344c2	tree \| snapshot
parent	25fdbf15b10cd1a861e73c799ab6334de5907ae5	commit \| diff

Fix a bug: Don't reuse buffers for MPI_Isend.

The intention of the code was clearly to cycle through the existing buffers,
but we never incremented the iterator, and so accidentally reused a send buffer over and
over. This works only because MPI_Isend is specified in the MPI standard as
'standard mode', which means that it may or may not copy the data to be sent
into an MPI-internal buffer before the function returns. Apparently it does in all
implementations we use, but we shouldn't rely on this.

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