Please see attached source file.
According to my understanding of MPI_Comm_spawn(), the intercommunicator
returned is the same as it is returned by MPI_Comm_get_parent() in the
spawned processes. I am assuming that there is one intercommunicator which
contains all the (spawned) child processes as well as the parent process. If
this is the case, then why does an MPI_Bcast() using such an
intercommunicator wait indefinately?