var p parser
	hdr.Size = p.parseNumeric(blk.toGNU().realSize())
	if p.err != nil {
		return nil, p.err
	}
	s := blk.toGNU().sparse()
	spd := make(sparseDatas, 0, s.maxEntries())
	for {
		for i := 0; i < s.maxEntries(); i++ {
			// This termination condition is identical to GNU and BSD tar.
			if s.entry(i).offset()[0] == 0x00 {
				break // Don't return, need to process extended headers (even if empty)
			}

		}
	}
}

func TestReadOldGNUSparseMap(t *testing.T) {
	populateSparseMap := func(sa sparseArray, sps []string) []string {
		for i := 0; len(sps) > 0 && i < sa.maxEntries(); i++ {
			copy(sa.entry(i), sps[0])
			sps = sps[1:]
		}
		if len(sps) > 0 {
			copy(sa.isExtended(), "\x80")
		}
		return sps
	}

      }
      Collection<Map.Entry<K, ImmutableCollection.Builder<V>>> mapEntries = builderMap.entrySet();
      if (keyComparator != null) {
        mapEntries = Ordering.from(keyComparator).<K>onKeys().immutableSortedCopy(mapEntries);
      }
      return ImmutableListMultimap.fromMapBuilderEntries(mapEntries, valueComparator);
    }
  }

  /**

      }
      Collection<Map.Entry<K, ImmutableCollection.Builder<V>>> mapEntries = builderMap.entrySet();
      if (keyComparator != null) {
        mapEntries = Ordering.from(keyComparator).<K>onKeys().immutableSortedCopy(mapEntries);
      }
      return ImmutableListMultimap.fromMapBuilderEntries(mapEntries, valueComparator);
    }
  }

  /**

          private final Iterator<Map.Entry<E, AtomicInteger>> mapEntries =
              countMap.entrySet().iterator();

          @Override
          protected @Nullable Entry<E> computeNext() {
            while (true) {
              if (!mapEntries.hasNext()) {
                return endOfData();
              }
              Map.Entry<E, AtomicInteger> mapEntry = mapEntries.next();
              int count = mapEntry.getValue().get();