diff --git a/unsupported/Eigen/src/IterativeSolvers/BiCGSTAB.h b/unsupported/Eigen/src/IterativeSolvers/BiCGSTAB.h
index 4f365bd96..d04158bb6 100644
--- a/unsupported/Eigen/src/IterativeSolvers/BiCGSTAB.h
+++ b/unsupported/Eigen/src/IterativeSolvers/BiCGSTAB.h
@@ -243,7 +243,7 @@ struct solve_retval<BiCGSTAB<_MatrixType, _Preconditioner>, Rhs>
 
   template<typename Dest> void evalTo(Dest& dst) const
   {
-    dst.setZero();
+    dst.setOnes();
     dec()._solve(rhs(),dst);
   }
 };