libstdc++-v3/testsuite/26_numerics/random/independent_bits_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::independent_bits_engine<std::mt19937, 9,
  28                                           std::uint_fast32_t>(sq);
  29   return std::uniform_int_distribution<int>()(rnd);
  30 }
  31
  32 int g(int x)
  33 {
  34   std::seed_seq sq(&x, &x + 1);
  35   auto rnd = std::independent_bits_engine<std::mt19937, 9,
  36                                           std::uint_fast32_t>();
  37   rnd.seed(sq);
  38   return std::uniform_int_distribution<int>()(rnd);
  39 }
  40
  41 void test01()
  42 {
  43   bool test __attribute__((unused)) = true;
  44
  45   const int f1 = f(0);
  46   const int f2 = f(0);
  47
  48   const int g1 = g(0);
  49   const int g2 = g(0);
  50
  51   VERIFY( f1 == f2 );
  52   VERIFY( g1 == g2 );
  53   VERIFY( f1 == g1 );
  54 }
  55
  56 int main()
  57 {
  58   test01();
  59   return 0;
  60 }