message: Fixed bug where possibly uninitialized vector was used
diff: @@ -435,6 +435,7 @@ class MultigridSolver : public Solver
  {
  // Safe const_cast, since x at the finest level will never be modified
  X.Last() = const_cast<Vector *>(&x);
  + y = 0.0;
  Y.Last() = &y;
  Cycle(opr->NumLevels() - 1);
  X.Last() = nullptr;
  