C++ 为什么此程序以“结束”结尾；未知信号；？_C++_Crash

C++ 为什么此程序以“结束”结尾；未知信号；？

c++

C++ 为什么此程序以“结束”结尾；未知信号；？,c++,crash,C++,Crash,以下代码旨在输出大小为1、2、…、N的组合，给定大小为N的输入集 #include <iostream> #include <fstream> #include <string> #include <deque> #include <cstring> #include <iomanip> #include <algorithm> #include <exception> template< t

以下代码旨在输出大小为1、2、…、N的组合，给定大小为N的输入集

#include <iostream>
#include <fstream>
#include <string>
#include <deque>
#include <cstring>
#include <iomanip>
#include <algorithm>
#include <exception>

template< typename V >
class Item
{
public:

  Item( const std::string& description,
        const V& value )
    : description_( description )
    , value_( value )
  {
  }

  std::string description() const { return description_; }

  V value() const { return value_; }

private:

  std::string description_;
  V value_;

friend std::ostream& operator<<( std::ostream& os, const Item& item )
{
  os << "{ \"" << item.description_ << "\", " << item.value_ << " }";
  return os;
}
};

template < typename T >
void addCombinationsN( const std::deque<T>& values,
                       std::deque<T>& interimResults,
                       size_t valuesStartIdx,
                       size_t n,
                       std::deque< std::deque<T> >& results )
{
  if ( valuesStartIdx >= values.size() ) { return; }
  if ( interimResults.size() >= n ) { return; }

  for ( int valuesIdx = valuesStartIdx;
        valuesIdx < values.size();
        ++valuesIdx )
  {
    interimResults.push_back( values[valuesIdx] );
    addCombinationsN( values, interimResults, valuesIdx+1, n, results );

    if ( interimResults.size() == n )
    {
      results.push_back( interimResults );
    }
    interimResults.pop_back();
  }
}

template < typename T >
std::deque< std::deque<T> > nChoose( const std::deque<T>& values )
{
  std::deque< std::deque<T> > retVal;
  std::deque<T> interimResults;

  std::cout << "adding all combinations from " << values.size() << " choices" << std::endl;

  for ( size_t n = 1; n <= values.size(); ++n )
  {
    std::cout << "# choices: " << n << std::endl;
    addCombinationsN < T > ( values, interimResults, 0, n, retVal );
  }
  std::cout << "done adding all choices" << std::endl;

  return retVal;
}

template< typename V >
class ItemDecCmp
{
public:
  bool operator()( std::deque< Item< V > >& a,
                   std::deque< Item< V > >& b ) const
  {
    return a.size() > b.size();
  }
};

template< typename V >
void populateChoices( std::deque< Item< V > >& items )
{
  for ( int i = 0; i < 28; ++i )
  {
    items.push_back( Item< V >( std::string( 1, '0' + i ), V(i) ) );
  }
}

int main( int argc, char* argv[] )
{
  std::deque< Item< double > > items;
  populateChoices<double>( items );

  std::deque< std::deque< Item< double > > > nChoices;
  nChoices = nChoose< Item< double > >( items );

  std::sort( nChoices.begin(), nChoices.end(), ItemDecCmp< double >() );
  std::cout << "done" << std::endl;

  for ( std::deque< std::deque< Item< double > > >::iterator i = nChoices.begin();
        i != nChoices.end();
        ++i )
  {
    for ( std::deque< Item< double > >::iterator j = i->begin();
          j != i->end();
          ++j )
    {
      std::cout << *j << " ";
    }
    std::cout << std::endl;
  }

  return 0;
}

输入28个元素的输出示例：

$ g++ -g main.cpp && ./a.exe
adding all combinations from 3 choices
# choices: 1
# choices: 2
# choices: 3
done adding all choices
done
{ "0", 0 } { "1", 1 } { "2", 2 }
{ "0", 0 } { "1", 1 }
{ "0", 0 } { "2", 2 }
{ "1", 1 } { "2", 2 }
{ "0", 0 }
{ "1", 1 }
{ "2", 2 }

$ g++ -g main.cpp && ./a.exe
adding all combinations from 28 choices
# choices: 1
# choices: 2
# choices: 3
# choices: 4
# choices: 5
# choices: 6
# choices: 7
# choices: 8
# choices: 9
# choices: 10
# choices: 11

我尝试解决问题的方法：
1）我怀疑由于递归算法，我可能会遇到堆栈溢出（没有双关语）。但是，增加堆栈大小并没有改变所描述的行为

$ ulimit -a core file size (blocks, -c) unlimited data seg size (kbytes, -d) unlimited file size (blocks, -f) unlimited open files (-n) 256 pipe size (512 bytes, -p) 8 stack size (kbytes, -s) 2032 cpu time (seconds, -t) unlimited max user processes (-u) 256 virtual memory (kbytes, -v) unlimited $ $ ulimit -s 65536 $ ulimit -a core file size (blocks, -c) unlimited data seg size (kbytes, -d) unlimited file size (blocks, -f) unlimited open files (-n) 256 pipe size (512 bytes, -p) 8 stack size (kbytes, -s) 65536 cpu time (seconds, -t) unlimited max user processes (-u) 256 virtual memory (kbytes, -v) unlimited $
2）此代码最初使用的是
std:：vector
，而不是
std:：deque
；我怀疑我的问题可能与随需应变的重新分配有关。我将容器切换到
std:：deque
，因为
push_-back
s和
pop_-back
s不会引起重新分配（，以及其他读取），但这也不会导致运行时行为的任何变化
3）我通过
gdb
运行了可执行文件，但无法告诉我它的堆栈跟踪告诉了我什么：

(gdb) r Starting program: /path/to/code/a.exe [New Thread 11212.0x1884] [New Thread 11212.0x18cc] adding all combinations from 28 choices # choices: 1 # choices: 2 # choices: 3 # choices: 4 # choices: 5 # choices: 6 [New Thread 11212.0x1eb4] # choices: 7 # choices: 8 # choices: 9 # choices: 10 [New Thread 11212.0x2a5c] [New Thread 11212.0xfa0] # choices: 11 gdb: unknown target exception 0x20474343 at 0x7ffccb2754d8 Thread 1 "a" received signal ?, Unknown signal. 0x00007ffccb2754d8 in RaiseException () from /cygdrive/c/WINDOWS/System32/KERNELBASE.dll (gdb) bt #0 0x00007ffccb2754d8 in RaiseException () from /cygdrive/c/WINDOWS/System32/KERNELBASE.dll #1 0x00000003e8ddcbf1 in cyggcc_s-seh-1!_Unwind_RaiseException () from /usr/bin/cyggcc_s-seh-1.dll #2 0x00000003e8ddccc0 in cyggcc_s-seh-1!_Unwind_Resume_or_Rethrow () from /usr/bin/cyggcc_s-seh-1.dll #3 0x00000003d0c57fcd in cygstdc++-6!.cxa_rethrow () from /usr/bin/cygstdc++-6.dll #4 0x0000000100402ef7 in std::_Deque_base<Item<double>, std::allocator<Item<double> > >::_M_initialize_map (this=0x6fff5d6f7a0, __num_elements=11) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/bits/stl_deque.h:707 #5 0x000000010040307a in std::_Deque_base<Item<double>, std::allocator<Item<double> > >::_Deque_base (this=0x6fff5d6f7a0, __a=..., __num_elements=11) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/bits/stl_deque.h:500 #6 0x0000000100405209 in std::deque<Item<double>, std::allocator<Item<double> > >::deque (this=0x6fff5d6f7a0, __x=...) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/bits/stl_deque.h:949 #7 0x000000010040213f in __gnu_cxx::new_allocator<std::deque<Item<double>, std::allocator<Item<double> > > >::construct<std::deque<Item<double>, std::allocator<Item<double> > >, std::deque<Item<double>, std::allocator<Item<double> > > const&> (this=0xffffcb20, __p=0x6fff5d6f7a0, __args#0=...) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/ext/new_allocator.h:136 #8 0x0000000100404506 in std::allocator_traits<std::allocator<std::deque<Item<double>, std::allocator<Item<double> > > > >::construct<std::deque<Item<double>, std::allocator<Item<double> > >, std::deque<Item<double>, std::allocator<Item<double> > > const&> (__a=..., __p=0x6fff5d6f7a0, __args#0=...) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/bits/alloc_traits.h:475 #9 0x0000000100405b04 in std::deque<std::deque<Item<double>, std::allocator<Item<double> > >, std::allocator<std::deque<Item<double>, std::allocator<Item<double> > > > >::push_back (this=0xffffcb20, __x=...) at /usr/lib/gcc/x86_64-pc-cygwin/7.3.0/include/c++/bits/stl_deque.h:1547 #10 0x0000000100401b08 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=20, n=11, results=...) at main.cpp:58 #11 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=17, n=11, results=...) at main.cpp:54 #12 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=15, n=11, results=...) at main.cpp:54 #13 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=12, n=11, results=...) at main.cpp:54 #14 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=10, n=11, results=...) at main.cpp:54 #15 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=9, n=11, results=...) at main.cpp:54 #16 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=6, n=11, results=...) at main.cpp:54 #17 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=5, n=11, results=...) at main.cpp:54 #18 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=4, n=11, results=...) at main.cpp:54 #19 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=2, n=11, results=...) at main.cpp:54 #20 0x0000000100401ae1 in addCombinationsN<Item<double> > (values=..., interimResults=..., valuesStartIdx=0, n=11, results=...) at main.cpp:54 #21 0x0000000100401c1f in nChoose<Item<double> > (values=...) at main.cpp:75 #22 0x00000001004010d7 in main (argc=1, argv=0xffffcc20) at main.cpp:108

PS-我很抱歉问一个“帮助我调试”的问题，但在这种情况下，因为我不知道如何理解
gdb
告诉我的内容，我真的遇到了如何识别具体错误的思想障碍。我在Meta上问过这个问题是否最适合在另一个Stack Exchange站点上使用，并且在这里和代码审查之间存在分歧。
根据堆栈跟踪，异常在调用中抛出

results.push_back( interimResults );
并且很可能是类型
std:：bad_alloc
的异常，表明无法为
std:：deque
分配新元素的内存，可能是因为没有足够的内存可用
因为
interimResults
总是从另一个位置快速返回
pop_
ed，所以它的大小不会太大。但是，
结果
将变得非常大，并将消耗所有可用内存

您根本无法存储那么多数据。你需要释放你不需要的东西。
检查你的内存消耗。是的，这看起来像是一个
坏的\u alloc
异常，我的系统也会产生它。您的程序在我的系统上使用了大约12个选项后使用了很多GB。Top是不可能的，但应该可以帮助您使用Windows。这意味着无法分配动态内存，是的。在本例中，由
deque:：push_back
抛出，这意味着无法分配新元素的内存。你根本无法在你的容器里储存那么多东西。摆脱你不再需要的东西。
addCombinationsN
做了大量的递归添加。有趣的是，将std:：cout放在反射上，高内存消耗是有意义的：给定N个选择，并且需要找到大小为1、2、…、N的所有组合，这些组合的总数是（2^N）-1，这在讨论~30个元素的输入大小时是巨大的。
results.push_back( interimResults );