Re: [Boost-users] boost MPI issue on windows

On 26 Oct 2010, at 15:52, Nick Collier wrote:

I winnowed my own code down to a simple scatter call. I get the error under release mode but not under debug. Here's the code:

namespace mpi = boost::mpi; int main(int argc, char **argv) { mpi::environment env(argc, argv); mpi::communicator world;

vector<int> out; vector in; if (world.rank() == 0) { for (int i = 0; i < world.size(); ++i) { vector<int> vec(10, 12); in.push_back(vec); } }

try { mpi::scatter(world, in, out, 0); } catch (std::exception& ex) { std::cerr << ex.what() << std::endl; throw ex; }

cout << world.rank() << " : " << out.size() << endl; }

And the error is:

ar size: 4293462132 MPI_Send: Invalid count, error stack: MPI_Send(176): MPI_Send(buf=0x0016F78C, count=-1505164, MPI_PACKED, dest=1, tag= 2147483647, MPI_COMM_WORLD) failed MPI_Send(101): Negative count, value is -1505164

This seems to happen in line 73 of boost/mpi/collectives/scatter.hpp . To see where exactly this optimization issue arises, could you please add a print statement std::cerr << oa.size() << std::endl; before line 73 to print the size of the archive there. Matthias