libstdc++-v3/testsuite/23_containers/unordered_set/max_load_factor/robustness.cc

   1 // { dg-options "-std=gnu++0x" }
   2
   3 // Copyright (C) 2011-2013 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10 //
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <unordered_set>
  21 #include <limits>
  22 #include <ext/throw_allocator.h>
  23 #include <testsuite_hooks.h>
  24
  25 void test01()
  26 {
  27   bool test __attribute__((unused)) = true;
  28
  29   typedef std::numeric_limits<std::size_t> nl_size_t;
  30   std::unordered_set<int, std::hash<int>, std::equal_to<int>,
  31                      __gnu_cxx::throw_allocator_limit<int> > us;
  32   int val = 0;
  33   for (; val != 100; ++val)
  34     {
  35       VERIFY( us.insert(val).second) ;
  36       VERIFY( us.load_factor() <= us.max_load_factor() );
  37     }
  38
  39   float cur_max_load_factor = us.max_load_factor();
  40   int counter = 0;
  41   std::size_t thrown_exceptions = 0;
  42   while (true)
  43     {
  44       __gnu_cxx::limit_condition::set_limit(counter++);
  45       bool do_break = false;
  46       try
  47         {
  48           us.max_load_factor(.5f);
  49           do_break = true;
  50         }
  51       catch (const __gnu_cxx::forced_error&)
  52         {
  53           VERIFY( us.max_load_factor() == cur_max_load_factor );
  54           ++thrown_exceptions;
  55         }
  56       // Lets check that unordered_set will still be correctly resized
  57       // when needed
  58       __gnu_cxx::limit_condition::set_limit(nl_size_t::max());
  59       for (;;)
  60         {
  61           VERIFY( us.load_factor() <= us.max_load_factor() );
  62           size_t nbkts = us.bucket_count();
  63           VERIFY( us.insert(val++).second );
  64           if (us.bucket_count() != nbkts)
  65             break;
  66         }
  67       if (do_break)
  68         break;
  69     }
  70   VERIFY( thrown_exceptions > 0 );
  71 }
  72
  73 int main()
  74 {
  75   test01();
  76   return 0;
  77 }