opal_unpack_general_function might upack too much data #2535
Description
@bosilca can you please take care of that ?
the following program works fine if both task run on homogeneous nodes, but fail otherwise.
i strongly suspect the root cause is opal_unpack_general_function that does not exit when the unpacked data reaches *max_data
#include <assert.h> #include <mpi.h> /* simple bug reproducer * task 0 MPI_Recv 2 MPI_INT but task 1 only MPI_Send 1 MPI_INT * ok on homogeneous node(s), ko on heterogeneous nodes */ int main(int argc, char *argv[]) { int b[2]; int rank; MPI_Status status; int count; int err; MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &rank); if (0 == rank) { b[0] = -1; b[1] = -1; err = MPI_Recv(b, 2, MPI_INT, 1, 0, MPI_COMM_WORLD, &status); assert(MPI_SUCCESS == err); err = MPI_Get_elements(&status, MPI_INT, &count); assert(MPI_SUCCESS == err); assert(1 == count); assert(0 == b[0]); assert(-1 == b[1]); // currently fails on heterogeneous nodes } else if (1 == rank) { b[0] = 0; b[1] = 2; MPI_Send(b, 1, MPI_INT, 0, 0, MPI_COMM_WORLD); } MPI_Finalize(); return 0; }