From ad89a1cfd0e6cbd38a770fc8d48fd3cc1bc00bcf Mon Sep 17 00:00:00 2001
From: Timo Heister <timo.heister@gmail.com>
Date: Thu, 21 Nov 2013 03:07:40 +0000
Subject: [PATCH] write own rand() function for the test suite because cygwin
 has a different implementation. I hope this will not break any test.

git-svn-id: https://svn.dealii.org/trunk@31745 0785d39b-7218-0410-832d-ea1e28bc413d
---
 tests/base/symmetric_tensor_25.cc           |  2 +-
 tests/base/symmetric_tensor_26.cc           |  4 +-
 tests/bits/fe_q_constraints.cc              |  4 +-
 tests/bits/full_matrix_56.cc                |  4 +-
 tests/bits/joa_1.cc                         |  4 +-
 tests/bits/point_value_hp_01.cc             |  2 +-
 tests/bits/point_value_hp_02.cc             |  2 +-
 tests/bits/rt_2.cc                          |  2 +-
 tests/fail/abf_approximation_01.cc          |  4 +-
 tests/fe/rt_approximation_01.cc             |  4 +-
 tests/fe/rt_normal_02.cc                    |  2 +-
 tests/hp/count_dofs_per_block_01.cc         |  2 +-
 tests/hp/count_dofs_per_block_02.cc         |  2 +-
 tests/hp/crash_10.cc                        |  4 +-
 tests/hp/hp_hanging_nodes_02.cc             |  2 +-
 tests/lac/full_matrix.cc                    |  4 +-
 tests/lac/full_matrix_02.cc                 |  2 +-
 tests/lac/full_matrix_03.cc                 |  2 +-
 tests/lac/full_matrix_04.cc                 | 10 ++--
 tests/lac/sparse_ilu.cc                     |  2 +-
 tests/lac/sparse_ilu_t.cc                   |  2 +-
 tests/lac/sparse_matrix_Tmmult_01.cc        |  8 +--
 tests/lac/sparse_matrix_Tmmult_02.cc        | 10 ++--
 tests/lac/sparse_matrix_mmult_01.cc         |  8 +--
 tests/lac/sparse_matrix_mmult_02.cc         | 10 ++--
 tests/lac/sparse_mic.cc                     |  2 +-
 tests/mpi/constraint_matrix_trilinos_bug.cc |  2 +-
 tests/mpi/mg_05.cc                          |  2 +-
 tests/mpi/mg_06.cc                          |  2 +-
 tests/mpi/p4est_2d_constraintmatrix_03.cc   |  2 +-
 tests/mpi/p4est_2d_constraintmatrix_04.cc   |  6 +-
 tests/mpi/p4est_3d_constraintmatrix_01.cc   |  2 +-
 tests/mpi/p4est_3d_constraintmatrix_02.cc   |  2 +-
 tests/mpi/p4est_3d_constraintmatrix_03.cc   |  6 +-
 tests/tests.h                               | 63 +++++++++++++++++++++
 35 files changed, 127 insertions(+), 64 deletions(-)

diff --git a/tests/base/symmetric_tensor_25.cc b/tests/base/symmetric_tensor_25.cc
index 6b74730049..d61f2359e4 100644
--- a/tests/base/symmetric_tensor_25.cc
+++ b/tests/base/symmetric_tensor_25.cc
@@ -33,7 +33,7 @@ void check ()
     {
       SymmetricTensor<2,dim> S;
       for (unsigned int i=0; i<S.n_independent_components; ++i)
-        S[S.unrolled_to_component_indices (i)] = std::rand () % 10;
+        S[S.unrolled_to_component_indices (i)] = rand() % 10;
 
       deallog << "S = " << S << std::endl;
       deallog << "first invariant  = " << first_invariant(S) << std::endl;
diff --git a/tests/base/symmetric_tensor_26.cc b/tests/base/symmetric_tensor_26.cc
index 50dfd226ee..59a6b28c44 100644
--- a/tests/base/symmetric_tensor_26.cc
+++ b/tests/base/symmetric_tensor_26.cc
@@ -30,11 +30,11 @@ void check ()
 {
   SymmetricTensor<2,dim> S;
   for (unsigned int i=0; i<S.n_independent_components; ++i)
-    S[S.unrolled_to_component_indices (i)] = std::rand () % 10;
+    S[S.unrolled_to_component_indices (i)] = rand() % 10;
 
   Tensor<1,dim> x;
   for (unsigned int i=0; i<dim; ++i)
-    x[i] = std::rand() % 10;
+    x[i] = rand() % 10;
 
   deallog << "S = " << S << std::endl;
   deallog << "x = " << x << std::endl;
diff --git a/tests/bits/fe_q_constraints.cc b/tests/bits/fe_q_constraints.cc
index de93aa18d0..743ea9d7a3 100644
--- a/tests/bits/fe_q_constraints.cc
+++ b/tests/bits/fe_q_constraints.cc
@@ -78,7 +78,7 @@ TestFunction<dim>::TestFunction (const unsigned int p_order) :
   for (unsigned int d = 0; d < dim; ++d)
     {
       for (unsigned int c = 0; c < p_order; ++c)
-        coeff[c] = (double) rand () / (double) RAND_MAX;
+        coeff[c] = (double) rand() / (double) RAND_MAX;
       base.push_back (Polynomials::Polynomial<double> (coeff));
     }
 }
@@ -138,7 +138,7 @@ void TestFEQConstraints<dim>::refine_grid_random ()
   Vector<double> estimated_error_per_cell (n_cells);
 
   for (unsigned int i = 0; i < n_cells; ++i)
-    estimated_error_per_cell(i) = (double) rand () / (double) RAND_MAX;
+    estimated_error_per_cell(i) = (double) rand() / (double) RAND_MAX;
 
   GridRefinement::refine_and_coarsen_fixed_number (triangulation,
                                                    estimated_error_per_cell,
diff --git a/tests/bits/full_matrix_56.cc b/tests/bits/full_matrix_56.cc
index ad3e2e518e..0476ad79d2 100644
--- a/tests/bits/full_matrix_56.cc
+++ b/tests/bits/full_matrix_56.cc
@@ -45,7 +45,7 @@ void random_matrix(FullMatrix<double> &A)
   for (unsigned int i=0; i<A.m(); ++i)
     for (unsigned int j=0; j<A.n(); ++j)
       {
-        double rnd = std::rand();
+        double rnd = rand();
         rnd /= RAND_MAX;
         A(i,j) = (i==j) ? A.m()+rnd : rnd;
       }
@@ -60,7 +60,7 @@ check ()
 //  deallog.attach(logfile);
   deallog.depth_console(0);
 //  deallog.threshold_double(1.e-10);
-  std::srand(3391466);
+  srand(3391466);
 
   FullMatrix<double> T2(2,2,entries2), S2(2,2), R2(2,2);
   FullMatrix<double>T3(3,3,entries3), S3(3,3), R3(3,3);
diff --git a/tests/bits/joa_1.cc b/tests/bits/joa_1.cc
index 2348eff411..577b874706 100644
--- a/tests/bits/joa_1.cc
+++ b/tests/bits/joa_1.cc
@@ -1073,8 +1073,8 @@ void LaplaceProblem<dim>::run ()
   // points inside a radius of 0.9)
   for (int i=0; i<1000; i++)
     {
-      double r = sqrt((0.9*std::rand()/RAND_MAX));
-      double phi = 2*3.14*(1.0*std::rand()/RAND_MAX);
+      double r = sqrt((0.9*rand()/RAND_MAX));
+      double phi = 2*3.14*(1.0*rand()/RAND_MAX);
       double x = r*cos(phi);
       double y = r*sin(phi);
       Point<2> p(x,y);
diff --git a/tests/bits/point_value_hp_01.cc b/tests/bits/point_value_hp_01.cc
index d9181f645a..de877e90a8 100644
--- a/tests/bits/point_value_hp_01.cc
+++ b/tests/bits/point_value_hp_01.cc
@@ -123,7 +123,7 @@ check ()
   endc = dof_handler.end();
   for (; cell!=endc; ++cell)
     {
-      cell->set_active_fe_index (std::rand() % fe.size());
+      cell->set_active_fe_index (rand() % fe.size());
     }
 
   dof_handler.distribute_dofs (fe);
diff --git a/tests/bits/point_value_hp_02.cc b/tests/bits/point_value_hp_02.cc
index 2db5a74c21..75e202e5dd 100644
--- a/tests/bits/point_value_hp_02.cc
+++ b/tests/bits/point_value_hp_02.cc
@@ -132,7 +132,7 @@ check ()
   endc = dof_handler.end();
   for (; cell!=endc; ++cell)
     {
-      cell->set_active_fe_index (std::rand() % fe.size());
+      cell->set_active_fe_index (rand() % fe.size());
     }
 
   dof_handler.distribute_dofs (fe);
diff --git a/tests/bits/rt_2.cc b/tests/bits/rt_2.cc
index 161a72db68..2b2b5755ec 100644
--- a/tests/bits/rt_2.cc
+++ b/tests/bits/rt_2.cc
@@ -158,7 +158,7 @@ int main ()
   // values between 0 and 1.
   Vector<double> solution(dof_handler.n_dofs ());
   for (unsigned int i = 0; i < dof_handler.n_dofs (); ++i)
-    solution(i) = (double) rand () / (double) RAND_MAX;
+    solution(i) = (double) rand() / (double) RAND_MAX;
 
   // Now check if the function is
   // continuous in normal direction
diff --git a/tests/fail/abf_approximation_01.cc b/tests/fail/abf_approximation_01.cc
index 65640ff9f0..b4cf3d7023 100644
--- a/tests/fail/abf_approximation_01.cc
+++ b/tests/fail/abf_approximation_01.cc
@@ -293,7 +293,7 @@ public:
       {
         for (unsigned int i=0; i < deg; ++i)
           {
-            double c = ((double) rand ()) / ((double) RAND_MAX + 1);
+            double c = ((double) rand()) / ((double) RAND_MAX + 1);
             coeff[i] = c;
           }
         polys.push_back (Polynomials::Polynomial<double> (coeff));
@@ -518,7 +518,7 @@ int main ()
     // Try arbitrary deformation ...
     for (unsigned int i=0; i < deformation.size (); ++i)
       {
-        double c = ((double) rand ()) / ((double) RAND_MAX + 1);
+        double c = ((double) rand()) / ((double) RAND_MAX + 1);
         deformation (i) = 0.35 * (c - 0.5);
       }
 
diff --git a/tests/fe/rt_approximation_01.cc b/tests/fe/rt_approximation_01.cc
index 04978dbc61..829acdb2d1 100644
--- a/tests/fe/rt_approximation_01.cc
+++ b/tests/fe/rt_approximation_01.cc
@@ -293,7 +293,7 @@ public:
       {
         for (unsigned int i=0; i < deg; ++i)
           {
-            double c = ((double) rand ()) / ((double) RAND_MAX + 1);
+            double c = ((double) rand()) / ((double) RAND_MAX + 1);
             coeff[i] = c;
           }
         polys.push_back (Polynomials::Polynomial<double> (coeff));
@@ -523,7 +523,7 @@ int main ()
     // Try arbitrary deformation ...
     for (unsigned int i=0; i < deformation.size (); ++i)
       {
-        double c = ((double) rand ()) / ((double) RAND_MAX + 1);
+        double c = ((double) rand()) / ((double) RAND_MAX + 1);
         deformation (i) = 0.35 * (c - 0.5);
       }
 
diff --git a/tests/fe/rt_normal_02.cc b/tests/fe/rt_normal_02.cc
index 154aa4bc2b..643189e1a9 100644
--- a/tests/fe/rt_normal_02.cc
+++ b/tests/fe/rt_normal_02.cc
@@ -291,7 +291,7 @@ int main (int /*argc*/, char **/*argv*/)
 
   // Fill solution vector with random values between 0 and 1.
   for (unsigned int i = 0; i < dof_handler->n_dofs (); ++i)
-    solution(i) = (double) rand () / (double) RAND_MAX;
+    solution(i) = (double) rand() / (double) RAND_MAX;
 
   // Now check if the function is continuous in normal
   // direction.
diff --git a/tests/hp/count_dofs_per_block_01.cc b/tests/hp/count_dofs_per_block_01.cc
index c60627beb1..98969008de 100644
--- a/tests/hp/count_dofs_per_block_01.cc
+++ b/tests/hp/count_dofs_per_block_01.cc
@@ -82,7 +82,7 @@ check ()
   cell = dof_handler.begin_active(),
   endc = dof_handler.end();
   for (; cell!=endc; ++cell)
-    cell->set_active_fe_index (std::rand() % fe.size());
+    cell->set_active_fe_index (rand() % fe.size());
 
   dof_handler.distribute_dofs (fe);
 
diff --git a/tests/hp/count_dofs_per_block_02.cc b/tests/hp/count_dofs_per_block_02.cc
index 1fee0b72fc..94649a1c01 100644
--- a/tests/hp/count_dofs_per_block_02.cc
+++ b/tests/hp/count_dofs_per_block_02.cc
@@ -82,7 +82,7 @@ check ()
   cell = dof_handler.begin_active(),
   endc = dof_handler.end();
   for (; cell!=endc; ++cell)
-    cell->set_active_fe_index (std::rand() % fe.size());
+    cell->set_active_fe_index (rand() % fe.size());
 
   dof_handler.distribute_dofs (fe);
 
diff --git a/tests/hp/crash_10.cc b/tests/hp/crash_10.cc
index 2a271e984c..6fd1c1c136 100644
--- a/tests/hp/crash_10.cc
+++ b/tests/hp/crash_10.cc
@@ -71,7 +71,7 @@ void test ()
   typename hp::DoFHandler<dim>::active_cell_iterator cell = dof_handler.begin_active (),
                                                      endc = dof_handler.end ();
   for (; cell != endc; ++cell)
-    cell->set_active_fe_index (random() % fe.size());
+    cell->set_active_fe_index (rand() % fe.size());
 
   dof_handler.distribute_dofs (fe);
 
@@ -113,7 +113,7 @@ int main ()
   // same value it has in
   // hp_hanging_nodes_02
   for (unsigned int i=0; i<64; ++i)
-    random ();
+    rand();
   test<3> ();
 
   return 0;
diff --git a/tests/hp/hp_hanging_nodes_02.cc b/tests/hp/hp_hanging_nodes_02.cc
index e9451b9f6d..f50d40925f 100644
--- a/tests/hp/hp_hanging_nodes_02.cc
+++ b/tests/hp/hp_hanging_nodes_02.cc
@@ -92,7 +92,7 @@ void run (bool random_p,
     {
       for (; cell != endc; ++cell)
         {
-          cell->set_active_fe_index ((int)(4.0 * (double) random () / (double) RAND_MAX));
+          cell->set_active_fe_index ((int)(4.0 * (double) rand() / (double) RAND_MAX));
         }
     }
   else
diff --git a/tests/lac/full_matrix.cc b/tests/lac/full_matrix.cc
index caba2e8000..a5620a12f9 100644
--- a/tests/lac/full_matrix.cc
+++ b/tests/lac/full_matrix.cc
@@ -37,7 +37,7 @@ void random_matrix(FullMatrix<double> &A)
   for (unsigned int i=0; i<A.m(); ++i)
     for (unsigned int j=0; j<A.n(); ++j)
       {
-        double rnd = std::rand();
+        double rnd = rand();
         rnd /= RAND_MAX;
         A(i,j) = (i==j) ? A.m()+rnd : rnd;
       }
@@ -52,7 +52,7 @@ main ()
   deallog.attach(logfile);
   deallog.depth_console(0);
   deallog.threshold_double(1.e-10);
-  std::srand(3391466);
+  srand(3391466);
 
   FullMatrix<double> T(3,3,entries);
   T.print_formatted(logfile, 0, false);
diff --git a/tests/lac/full_matrix_02.cc b/tests/lac/full_matrix_02.cc
index 5e8d478e0e..835e2c4723 100644
--- a/tests/lac/full_matrix_02.cc
+++ b/tests/lac/full_matrix_02.cc
@@ -44,7 +44,7 @@ main ()
   deallog.attach(logfile);
   deallog.depth_console(0);
   deallog.threshold_double(1.e-10);
-  std::srand(3391466);
+  srand(3391466);
 
   FullMatrix<double> A(3,3,entries_A);
   FullMatrix<double> B(3,3,entries_B);
diff --git a/tests/lac/full_matrix_03.cc b/tests/lac/full_matrix_03.cc
index 7a349f31fe..3a6b7ea6fa 100644
--- a/tests/lac/full_matrix_03.cc
+++ b/tests/lac/full_matrix_03.cc
@@ -44,7 +44,7 @@ main ()
   deallog.attach(logfile);
   deallog.depth_console(0);
   deallog.threshold_double(1.e-10);
-  std::srand(3391466);
+  srand(3391466);
 
   FullMatrix<double> A(3,3,entries_A);
   FullMatrix<double> B(3,3,entries_B);
diff --git a/tests/lac/full_matrix_04.cc b/tests/lac/full_matrix_04.cc
index ea997a7db1..22083f23b3 100644
--- a/tests/lac/full_matrix_04.cc
+++ b/tests/lac/full_matrix_04.cc
@@ -52,16 +52,16 @@ void test (const unsigned int n, const unsigned int m)
   for (unsigned int i=0; i<n; ++i)
     {
       for (unsigned int j=0; j<n; ++j)
-        A(i,j) = std::rand();
+        A(i,j) = rand();
       for (unsigned int j=0; j<m; ++j)
         {
-          B(i,j) = Bt(j,i) = std::rand();
-          D(j,i) = Dt(i,j) = std::rand();
+          B(i,j) = Bt(j,i) = rand();
+          D(j,i) = Dt(i,j) = rand();
         }
     }
   for (unsigned int i=0; i<m; ++i)
     for (unsigned int j=0; j<m; ++j)
-      C(i,j) = std::rand();
+      C(i,j) = rand();
 
   // Compare first Schur complement
   // with mmult.
@@ -123,7 +123,7 @@ main ()
   std::ofstream logfile(logname.c_str());
   deallog.attach(logfile);
   deallog.depth_console(0);
-  std::srand(3391466);
+  srand(3391466);
 
   test(3,4);
   test(4,7);
diff --git a/tests/lac/sparse_ilu.cc b/tests/lac/sparse_ilu.cc
index 339cc14f86..6b17880f8c 100644
--- a/tests/lac/sparse_ilu.cc
+++ b/tests/lac/sparse_ilu.cc
@@ -103,7 +103,7 @@ int main()
           for (unsigned int i=0; i<3; ++i)
             {
               for (unsigned int j=0; j<dim; ++j)
-                v(j) = 1. * std::rand()/RAND_MAX;
+                v(j) = 1. * rand()/RAND_MAX;
 
               A.vmult (tmp1, v);
               ilu.vmult (tmp2, tmp1);
diff --git a/tests/lac/sparse_ilu_t.cc b/tests/lac/sparse_ilu_t.cc
index 5f18c4baad..9bdab5450c 100644
--- a/tests/lac/sparse_ilu_t.cc
+++ b/tests/lac/sparse_ilu_t.cc
@@ -104,7 +104,7 @@ int main()
           for (unsigned int i=0; i<3; ++i)
             {
               for (unsigned int j=0; j<dim; ++j)
-                v(j) = 1. * std::rand()/RAND_MAX;
+                v(j) = 1. * rand()/RAND_MAX;
 
               A.Tvmult (tmp1, v);
               ilu.Tvmult (tmp2, tmp1);
diff --git a/tests/lac/sparse_matrix_Tmmult_01.cc b/tests/lac/sparse_matrix_Tmmult_01.cc
index 3eca2c82d8..26a45c21ab 100644
--- a/tests/lac/sparse_matrix_Tmmult_01.cc
+++ b/tests/lac/sparse_matrix_Tmmult_01.cc
@@ -56,9 +56,9 @@ void test (const unsigned int n)
   for (unsigned int i=0; i<n; ++i)
     {
       for (unsigned int j=0; j<n; ++j)
-        A.set(i,j,std::rand());
+        A.set(i,j,rand());
       for (unsigned int j=0; j<n; ++j)
-        B.set(i,j,std::rand());
+        B.set(i,j,rand());
     }
 
   // now form the matrix-matrix product and
@@ -67,7 +67,7 @@ void test (const unsigned int n)
 
   Vector<double> x(n), y(n), z(n), tmp(n);
   for (unsigned int j=0; j<n; ++j)
-    x(j) = std::rand();
+    x(j) = rand();
 
   // then test for correctness
   C.vmult (y, x);
@@ -90,7 +90,7 @@ main ()
   std::ofstream logfile(logname.c_str());
   deallog.attach(logfile);
   deallog.depth_console(0);
-  std::srand(3391466);
+  srand(3391466);
 
   test(3);
   test(7);
diff --git a/tests/lac/sparse_matrix_Tmmult_02.cc b/tests/lac/sparse_matrix_Tmmult_02.cc
index 0d5df1743e..8d5fe44018 100644
--- a/tests/lac/sparse_matrix_Tmmult_02.cc
+++ b/tests/lac/sparse_matrix_Tmmult_02.cc
@@ -56,14 +56,14 @@ void test (const unsigned int n)
   for (unsigned int i=0; i<n; ++i)
     {
       for (unsigned int j=0; j<n; ++j)
-        A.set(i,j,std::rand());
+        A.set(i,j,rand());
       for (unsigned int j=0; j<n; ++j)
-        B.set(i,j,std::rand());
+        B.set(i,j,rand());
     }
 
   Vector<double> v(n);
   for (unsigned int j=0; j<n; ++j)
-    v(j) = std::rand();
+    v(j) = rand();
 
   // now form the matrix-matrix product and
   // initialize a test rhs
@@ -71,7 +71,7 @@ void test (const unsigned int n)
 
   Vector<double> x(n), y(n), z(n), tmp(n);
   for (unsigned int j=0; j<n; ++j)
-    x(j) = std::rand();
+    x(j) = rand();
 
   // then test for correctness
   C.vmult (y, x);
@@ -95,7 +95,7 @@ main ()
   std::ofstream logfile(logname.c_str());
   deallog.attach(logfile);
   deallog.depth_console(0);
-  std::srand(3391466);
+  srand(3391466);
 
   test(3);
   test(7);
diff --git a/tests/lac/sparse_matrix_mmult_01.cc b/tests/lac/sparse_matrix_mmult_01.cc
index bc825f9832..1a4f952443 100644
--- a/tests/lac/sparse_matrix_mmult_01.cc
+++ b/tests/lac/sparse_matrix_mmult_01.cc
@@ -56,9 +56,9 @@ void test (const unsigned int n)
   for (unsigned int i=0; i<n; ++i)
     {
       for (unsigned int j=0; j<n; ++j)
-        A.set(i,j,std::rand());
+        A.set(i,j,rand());
       for (unsigned int j=0; j<n; ++j)
-        B.set(i,j,std::rand());
+        B.set(i,j,rand());
     }
 
   // now form the matrix-matrix product and
@@ -67,7 +67,7 @@ void test (const unsigned int n)
 
   Vector<double> x(n), y(n), z(n), tmp(n);
   for (unsigned int j=0; j<n; ++j)
-    x(j) = std::rand();
+    x(j) = rand();
 
   // then test for correctness
   C.vmult (y, x);
@@ -90,7 +90,7 @@ main ()
   std::ofstream logfile(logname.c_str());
   deallog.attach(logfile);
   deallog.depth_console(0);
-  std::srand(3391466);
+  srand(3391466);
 
   test(3);
   test(7);
diff --git a/tests/lac/sparse_matrix_mmult_02.cc b/tests/lac/sparse_matrix_mmult_02.cc
index 1e6f9ade5c..ea7f74a9ae 100644
--- a/tests/lac/sparse_matrix_mmult_02.cc
+++ b/tests/lac/sparse_matrix_mmult_02.cc
@@ -56,14 +56,14 @@ void test (const unsigned int n)
   for (unsigned int i=0; i<n; ++i)
     {
       for (unsigned int j=0; j<n; ++j)
-        A.set(i,j,std::rand());
+        A.set(i,j,rand());
       for (unsigned int j=0; j<n; ++j)
-        B.set(i,j,std::rand());
+        B.set(i,j,rand());
     }
 
   Vector<double> v(n);
   for (unsigned int j=0; j<n; ++j)
-    v(j) = std::rand();
+    v(j) = rand();
 
   // now form the matrix-matrix product and
   // initialize a test rhs
@@ -71,7 +71,7 @@ void test (const unsigned int n)
 
   Vector<double> x(n), y(n), z(n), tmp(n);
   for (unsigned int j=0; j<n; ++j)
-    x(j) = std::rand();
+    x(j) = rand();
 
   // then test for correctness
   C.vmult (y, x);
@@ -95,7 +95,7 @@ main ()
   std::ofstream logfile(logname.c_str());
   deallog.attach(logfile);
   deallog.depth_console(0);
-  std::srand(3391466);
+  srand(3391466);
 
   test(3);
   test(7);
diff --git a/tests/lac/sparse_mic.cc b/tests/lac/sparse_mic.cc
index c7986cfd47..f71321fd7f 100644
--- a/tests/lac/sparse_mic.cc
+++ b/tests/lac/sparse_mic.cc
@@ -105,7 +105,7 @@ int main()
           for (unsigned int i=0; i<3; ++i)
             {
               for (unsigned int j=0; j<dim; ++j)
-                v(j) = 1. * std::rand()/RAND_MAX;
+                v(j) = 1. * rand()/RAND_MAX;
 
               A.vmult (tmp1, v);
               mic.vmult (tmp2, tmp1);
diff --git a/tests/mpi/constraint_matrix_trilinos_bug.cc b/tests/mpi/constraint_matrix_trilinos_bug.cc
index 20f6b418d7..4dd55b0105 100644
--- a/tests/mpi/constraint_matrix_trilinos_bug.cc
+++ b/tests/mpi/constraint_matrix_trilinos_bug.cc
@@ -68,7 +68,7 @@ void test()
       endc = tr.end();
 
       for (; cell!=endc; ++cell)
-        if (std::rand()%42==1)
+        if (rand()%42==1)
           cell->set_refine_flag ();
 
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/mg_05.cc b/tests/mpi/mg_05.cc
index a2c66e45c9..2e95297318 100644
--- a/tests/mpi/mg_05.cc
+++ b/tests/mpi/mg_05.cc
@@ -101,7 +101,7 @@ void test()
         endc = tr.end();
       
       for (; cell!=endc; ++cell)
-	if (std::rand()%42==1)
+	if (rand()%42==1)
 	  cell->set_refine_flag ();
       
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/mg_06.cc b/tests/mpi/mg_06.cc
index 285c28d933..9d38193161 100644
--- a/tests/mpi/mg_06.cc
+++ b/tests/mpi/mg_06.cc
@@ -103,7 +103,7 @@ void test()
         endc = tr.end();
       
       for (; cell!=endc; ++cell)
-	if (std::rand()%42==1)
+	if (rand()%42==1)
 	  cell->set_refine_flag ();
       
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/p4est_2d_constraintmatrix_03.cc b/tests/mpi/p4est_2d_constraintmatrix_03.cc
index c7bab7f9a3..c8ccf8c3f5 100644
--- a/tests/mpi/p4est_2d_constraintmatrix_03.cc
+++ b/tests/mpi/p4est_2d_constraintmatrix_03.cc
@@ -123,7 +123,7 @@ void test()
       endc = tr.end();
 
       for (; cell!=endc; ++cell)
-        if (std::rand()%42==1)
+        if (rand()%42==1)
           cell->set_refine_flag ();
 
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/p4est_2d_constraintmatrix_04.cc b/tests/mpi/p4est_2d_constraintmatrix_04.cc
index d5940f956f..d256954daa 100644
--- a/tests/mpi/p4est_2d_constraintmatrix_04.cc
+++ b/tests/mpi/p4est_2d_constraintmatrix_04.cc
@@ -160,7 +160,7 @@ void test()
         endc = tr.end();
 
         for (; cell!=endc; ++cell)
-          if (std::rand()%42==1)
+          if (rand()%42==1)
             cell->set_refine_flag ();
 
         tr.execute_coarsening_and_refinement ();
@@ -200,9 +200,9 @@ void test()
         for (; cell!=endc; ++cell)
           if (!cell->is_artificial() && !cell->is_ghost())
             {
-              if (std::rand()%12==1)
+              if (rand()%12==1)
                 cell->set_refine_flag ();
-              else if (std::rand()%7==1)
+              else if (rand()%7==1)
                 cell->set_coarsen_flag ();
             }
       }
diff --git a/tests/mpi/p4est_3d_constraintmatrix_01.cc b/tests/mpi/p4est_3d_constraintmatrix_01.cc
index 57dc4fbc4d..e35d11ca0e 100644
--- a/tests/mpi/p4est_3d_constraintmatrix_01.cc
+++ b/tests/mpi/p4est_3d_constraintmatrix_01.cc
@@ -60,7 +60,7 @@ void test()
       endc = tr.end();
 
       for (; cell!=endc; ++cell)
-        if (std::rand()%42==1)
+        if (rand()%42==1)
           cell->set_refine_flag ();
 
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/p4est_3d_constraintmatrix_02.cc b/tests/mpi/p4est_3d_constraintmatrix_02.cc
index 46d10f0563..6d0d656f50 100644
--- a/tests/mpi/p4est_3d_constraintmatrix_02.cc
+++ b/tests/mpi/p4est_3d_constraintmatrix_02.cc
@@ -60,7 +60,7 @@ void test()
       endc = tr.end();
 
       for (; cell!=endc; ++cell)
-        if (std::rand()%42==1)
+        if (rand()%42==1)
           cell->set_refine_flag ();
 
       tr.execute_coarsening_and_refinement ();
diff --git a/tests/mpi/p4est_3d_constraintmatrix_03.cc b/tests/mpi/p4est_3d_constraintmatrix_03.cc
index b30e4008e3..6366dbae46 100644
--- a/tests/mpi/p4est_3d_constraintmatrix_03.cc
+++ b/tests/mpi/p4est_3d_constraintmatrix_03.cc
@@ -159,7 +159,7 @@ void test()
         endc = tr.end();
 
         for (; cell!=endc; ++cell)
-          if (std::rand()%42==1)
+          if (rand()%42==1)
             cell->set_refine_flag ();
 
         tr.execute_coarsening_and_refinement ();
@@ -199,9 +199,9 @@ void test()
         for (; cell!=endc; ++cell)
           if (!cell->is_artificial() && !cell->is_ghost())
             {
-              if (std::rand()%12==1)
+              if (rand()%12==1)
                 cell->set_refine_flag ();
-              else if (std::rand()%7==1)
+              else if (rand()%7==1)
                 cell->set_coarsen_flag ();
             }
       }
diff --git a/tests/tests.h b/tests/tests.h
index fadd4b7fc6..c7cf65ac83 100644
--- a/tests/tests.h
+++ b/tests/tests.h
@@ -33,6 +33,69 @@
 #include <iomanip>
 
 
+// Cygwin has a different implementation for rand() which causes many tests to fail.
+// This here is a reimplementation that gives the same sequence of numbers as a program
+// that uses rand() on a typical linux machine.
+int myrand(bool reseed=false, int seed=1)
+{
+  static int r[32];
+  static int k;
+  static bool inited=false;
+  if (!inited || reseed)
+    {
+      //srand treats a seed 0 as 1 for some reason
+      r[0]=(seed==0)?1:seed;
+
+      for (int i=1; i<31; i++)
+        {
+          r[i] = (16807LL * r[i-1]) % 2147483647;
+          if (r[i] < 0)
+            r[i] += 2147483647;
+        }
+      k=31;
+      for (int i=31; i<34; i++)
+        {
+          r[k%32] = r[(k+32-31)%32];
+          k=(k+1)%32;
+        }
+
+      for (int i=34; i<344; i++)
+        {
+          r[k%32] = r[(k+32-31)%32] + r[(k+32-3)%32];
+          k=(k+1)%32;
+        }
+      inited=true;
+      if (reseed==true)
+        return 0;// do not generate new no
+    }
+
+  r[k%32] = r[(k+32-31)%32] + r[(k+32-3)%32];
+  int ret = r[k%32];
+  k=(k+1)%32;
+  return (unsigned int)ret >> 1;
+}
+
+// reseed our random number generator
+void mysrand(int seed)
+{
+  myrand(true, seed);
+}
+
+
+// I hope this is safe to just override the standard
+// rand() functions here.
+int rand()
+{
+  return myrand();
+}
+
+void srand(int seed)
+{
+  mysrand(seed);
+}
+
+
+
 // given the name of a file, copy it to deallog
 // and then delete it
 inline void cat_file(const char *filename)
-- 
2.39.5