Function method_exposes_self_field 

fn method_exposes_self_field(
    tcx: TyCtxt<'_>,
    method: DefId,
    self_local: Local,
    field_index: usize,
) -> bool

Whether method returns a raw-pointer-bearing value derived from the field field_index of the struct borrowed via self_local, i.e. it leaks the raw field to the caller.