message: Print fn name and type in dump_allocs.
diff: @@ -418,9 +418,9 @@ impl<'a, 'tcx> Memory<'a, 'tcx> {
  let alloc = match (self.alloc_map.get(&id), self.functions.get(&id)) {
  (Some(a), None) => a,
  - (None, Some(_)) => {
  - // FIXME: print function name
  - trace!("{} function pointer", msg);
  + (None, Some(fn_def)) => {
  + let name = ty::tls::with(|tcx| tcx.item_path_str(fn_def.def_id));
  + trace!("{} function pointer: {}: {}", msg, name, fn_def.sig);
  continue;
  },
  (None, None) => {
  