I can try doing that. But for now: for (unsigned int i=0;i<world.size();i++) { if (particles_to_be_sent[i].size()>0) { ghosts_to_be_sent[i].part_crossed_send()='b'; world.isend(i,20,particles_to_be_sent[i]); } } mpi::all_to_all(world,ghosts_to_be_sent,ghosts_received); //receive particles for (int recv_rank=0;recv_rank<world.size();recv_rank++) { if (ghosts_received[recv_rank].part_crossed_send()=='b') { world.recv(recv_rank,20,particles_received); //this line fails for (unsigned int i=0;i<particles_received.size();i++) { //do stuff } } for (unsigned int j=0;j<ghosts_received[recv_rank].ghosts_to_send().size();j++) { //do stuff } } From: Boost-users [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Júlio Hoffimann Sent: Friday, January 04, 2013 1:38 PM To: boost-users@lists.boost.org Subject: Re: [Boost-users] boost-mpi assertion during recv fails Hello, I am using boost-mpi and I am getting an error that I am having a hard time figuring out. I am using a recv call and an assertion in the boost code fails: void boost::mpi::binary_buffer_iprimitive::load_impl(void *, int): Assertion `position+l<=static_cast<int>(buffer_.size())' Hi Kyle, You have to provide some code if you want us to help you. It's basically impossible to conclude anything with a single assertion fail. Do a test case, reduce it to the simplest scenario you can and start pulling back the complexity of your original code. It's tedious, but always works. Regards, Júlio.