Source: openmpi Followup-For: Bug #995599 Not so simple to make a minimal test case I think.
all_to_all is defined in cpp/dolfinx/common/MPI.h in dolfinx source, and calls MPI_Alltoall from openmpi. It's designed to use with graph::AdjacencyList<T> from graph/AdjacencyList.h, and is called from compute_nonlocal_dual_graph() in mesh/graphbuild.cpp, where T is set to std::int64_t. I tried grabbing dolfinx' all_to_all and use it with a pared down version of AdjacencyList. But it's not triggering the segfault on an i386 chroot. Possibly because I haven't populated it with an actual graph so there's nothing to send with MPI_Alltoall.
