Should be fine. Once MPI_Send returns, it should be safe to reuse the
buffer. In fact, the return of the call is the only way you have of
checking that the message has left the user's send buffer. The case
you're worried about is probably MPI_Isend, where you have to check
completion with an MPI_Test* or MPI_Wait* call.
On 9/19/2011 6:26 AM, Sébastien Boisvert wrote:
> Is it safe to re-use the same buffer (variable A) for MPI_Send and MPI_Recv given that MPI_Send may be eager depending on
> the MCA parameters ?