fenics

utils::ptr_vector<T> serves a similar purpose like smart pointers from std. We should remove this implementation in favor of smart pointers from std.

I already took care of replacing utils::ptr_vector<T> with std::unique_ptr in precice/precice#1159, but there are many more places, where utils::ptr_vector<T> is used.

The actual ghostUpdate is truly needed only in very few places, for most local operations one knows the value for ghosts without communication.

This

u.vector.copy(result=u0.vector)
u0.vector.ghostUpdate(addv=PETSc.InsertMode.INSERT, mode=PETSc.ScatterMode.FORWARD)

could become

with u0.vector.localForm() as loc0, u.vector.localForm() as loc:
    loc.copy(loc0)
``

and link to Github discussions Q&A.