libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/55215.cc

   1 // { dg-options "-std=gnu++11" }
   2 // { dg-require-cstdint "" }
   3 //
   4 // Copyright (C) 2012-2013 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11 //
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <random>
  22 #include <testsuite_hooks.h>
  23
  24 int f(int x)
  25 {
  26   std::seed_seq sq(&x, &x + 1);
  27   auto rnd = std::knuth_b(sq);
  28   return std::uniform_int_distribution<int>()(rnd);
  29 }
  30
  31 int g(int x)
  32 {
  33   std::seed_seq sq(&x, &x + 1);
  34   auto rnd = std::knuth_b();
  35   rnd.seed(sq);
  36   return std::uniform_int_distribution<int>()(rnd);
  37 }
  38
  39 void test01()
  40 {
  41   bool test __attribute__((unused)) = true;
  42
  43   const int f1 = f(0);
  44   const int f2 = f(0);
  45
  46   const int g1 = g(0);
  47   const int g2 = g(0);
  48
  49   VERIFY( f1 == f2 );
  50   VERIFY( g1 == g2 );
  51   VERIFY( f1 == g1 );
  52 }
  53
  54 int main()
  55 {
  56   test01();
  57   return 0;
  58 }