Ticket #7471: unordered_bug.cxx

// unordered_bug.cxx  
// Crash with unordered_multimap::erase(iterator, iterator)

// g++ -m64 unordered_bug.cxx -O3 -o unordered_bug -I/wrk/hdstaff/stevenl/p4/work_tmp/HEAD/src/ext/Boost/boost_1_51_0


#include <iostream>
#include "boost/unordered_map.hpp"

double
msec(clock_t start, clock_t end)
{
  return ((end - start) * 1000/CLOCKS_PER_SEC);
}

void
fill_unordered(int items)
{
  boost::unordered_multimap<int, int> hashmap;

  for (int i=0,j=items-1; i<j; ++i,--j)
  {
    hashmap.insert(boost::unordered_multimap<int, int>::value_type(i, i));
    hashmap.insert(boost::unordered_multimap<int, int>::value_type(i, i+1));

    if (i > 2) {
#if 1
      // crash
      std::pair<boost::unordered_multimap<int, int>::iterator, boost::unordered_multimap<int, int>::iterator> p = hashmap.equal_range(i - 2);

      hashmap.erase(p.first, p.second);
#else
      // fine
      hashmap.erase(i-2);
#endif
    }
  }
}


void
fill (int items)
{
  {
    std::cout << "filling unordered\n";
    clock_t start = clock();

    fill_unordered(items);

    clock_t end = clock();
    std::cout << "elapsed time: " << msec(start,end) << "ms\n";
  }
}

int main(int argc, char* argv[])
{
  if (argc < 2) {
    std::cout << "usage: fill <int>\n";
    return 1;
  }

  int items = std::atoi(argv[1]);
  std::cout << "items: " << items << "\n";
  fill(items);
  return 0;
}