voloctree: fix _recoverPartition method

src/voloctree/voloctree_mapper.cpp

@@ -1237,13 +1237,21 @@ bool VolOctreeMapper::_recoverPartition()
     for (int reference_rank : toreference_rank[m_rank]) {
         uint64_t reference_first_morton = partitionFDReference[reference_rank];
         uint64_t reference_last_morton = partitionLDReference[reference_rank];
+        // Initialize idx position in mapped tree to the first mapped
+        // octant inside the overlapping region
         while (morton < reference_first_morton) {
             idx++;
             if (idx == mappedPatch->getTree().getNumOctants()) {
                 break;
             }
             morton = mappedPatch->getTree().getLastDescMorton(idx);
         }
+        if (idx == mappedPatch->getTree().getNumOctants()) {
+            continue;
+        }
+        // Fill partitioning info structure with mapped octants in the
+        // overlapping region
+        morton = mappedPatch->getTree().getMorton(idx);
         while (morton < reference_last_morton) {
             Octant oct = *mappedPatch->getTree().getOctant(idx);
             list_octant[reference_rank].push_back(oct);