Hi, I'm working on r21949 of the trunk.
When I run on a single node with 4 processes this simple program calling 2 times MPI_Comm_dup , the processes hang from time to time in the 2nd dup.
int main(int argc, char *argv[]) { MPI_Comm comm,comm2; MPI_Init(&argc, &argv); MPI_Comm_dup(MPI_COMM_WORLD,&comm); MPI_Comm_dup(comm,&comm2); .... } Thomas