--- /dev/null
+// ------------------------------------------------------------------------
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2005 - 2020 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
+//
+// ------------------------------------------------------------------------
+
+// Test that an assertion is thrown if output argument of FullMatrix::mmult() is
+// also an input argument
+
+#include <deal.II/lac/full_matrix.h>
+
+#include "../tests.h"
+
+int
+main()
+{
+ initlog();
+ deallog << std::setprecision(2);
+ deallog << std::fixed;
+
+ dealii::FullMatrix<double> A(2, 2);
+ dealii::FullMatrix<double> B(2, 2);
+ dealii::FullMatrix<double> C(4, 4);
+
+ A(0, 0) = 1;
+ A(0, 1) = 2;
+ A(1, 0) = 3;
+ A(1, 1) = 4;
+
+ B(0, 0) = 5;
+ B(0, 1) = 6;
+ B(1, 0) = 7;
+ B(1, 1) = 8;
+
+ C.kronecker_product(A, B);
+
+
+ std::stringstream sstring;
+ sstring << "Result" << "\n";
+ C.print_formatted(sstring, 4, true, 10, "0.");
+ deallog << sstring.str() << std::endl;
+
+ return 0;
+}