Question

当我尝试在cygwin中运行我的程序时，我所做的以下功能导致错误“Aborted（core dumped）”。我尝试使用gdb，然后得到：

“程序接收信号SIGABRT，已中止。 0x00000000在？（）“

我先尝试过擦除你，然后我，但这会产生相同的结果，第二次擦除时会崩溃（在这种情况下擦除（我））。

CoalesceOverlaps函数的基本思想是组合自身重叠的OVERLAP，因此我对列表进行排序，检查两个相邻的（me＆amp; thee）元素是否重叠，如果它们重叠，则创建一个新元素，即组合我和我你，删除我＆amp;然后将它们替换为组合的新元素。

该功能在逻辑上有效，因为我用一个完整元素的手的硬编码列表进行测试，并且输出正确地合并，但当我尝试在我的真实程序中实现它时，它有大型列表/空列表等，它失败。

编辑（来自cnvr_check_v1.1.exe.stackdump）：

Stack trace:
Frame     Function  Args
0028A624  76E31194  (000000E8, 0000EA60, 00000000, 0028A758)
0028A638  76E31148  (000000E8, 0000EA60, 000000A4, 0028A734)
0028A758  610DC559  (00000001, 80038390, 0000001D, 610EBCCC)
0028A848  610D9913  (00000000, 0028A890, 0028A878, 61187784)
0028A8A8  610D9DEE  (0028FF14, 00000001, 0028A8E8, 00000006)
0028A958  610D9F40  (00000158, 00000006, 0053002B, 61187784)
0028A978  610D9F6C  (00000006, 00000006, 0028A9A8, 610B66D1)
0028A9A8  610DA233  (00000000, 0028A9DC, 0028A9C8, 610FD3CA)
End of stack trace

代码：

void CoalesceOverlaps(list<OVERLAP>& overlap_regions)
{
cout << "Begining of CoalesceOverlaps function\n";
overlap_regions.sort(OVERLAPStartSortPredicate);
//now coalesce
cout << "Didn't fail during sorting\n";

list<OVERLAP>::iterator me = overlap_regions.begin(),
                           end = overlap_regions.end();

if ( me != end ) // Treat empty list
    for(list<OVERLAP>::iterator thee = ++me; // Post-increment 
        thee != end; 
        me++, thee++)
    {

        cout << "just before thee-> start less than... if\n";
        //cout << me->stop << endl;
        if(thee->start <= me->stop) //hit to coalesce them
        {
            cout << "thee->ID:" << thee->id << endl;
            cout << "thee->start:" << thee->start << endl;
            cout << "made it to the thee->start less than me->stop if\n";
            long temp_start = min(thee->start,me->start),temp_stop = max(thee->stop,me->stop);
            OVERLAP temp_region;
            temp_region.start = temp_start;
            temp_region.stop = temp_stop;
            cout << "just before the first erase\n";
            //overlap_regions.push_front(temp_region);
            list<OVERLAP>::iterator temp_itr = overlap_regions.erase(me);

            cout << "thee->ID:" << thee->id << endl;
            cout << "thee->start:" << thee->start << endl;

            cout << "just before the second erase\n";
            //cout << thee->id;
            overlap_regions.erase(thee);
            cout << "past the erases\n";
            overlap_regions.insert(temp_itr,temp_region);
        }
        cout << "bottom of the for\n";
    }
cout << "End of CoalesceOverlaps function\n";

}

编辑（下面更正的功能）谢谢！：

void CoalesceOverlaps(list<OVERLAP>& overlap_regions)
{
overlap_regions.sort(OVERLAPStartSortPredicate);

//iterators for keeping track of the two nodes we are comparing
list<OVERLAP>::iterator me = overlap_regions.begin(),
                        thee = overlap_regions.begin(),
                           end = overlap_regions.end();


if ( me != end ) // Treat empty list
    thee++; //sets it to the second element
    if(thee!=end)   //Treat list with one element
        while(thee != end)  //lets keep comparing until we right the end
        {
            if(thee->start <= me->stop) //hit to coalesce them
            {
                long temp_start = min(thee->start,me->start),temp_stop = max(thee->stop,me->stop);
                OVERLAP temp_region;
                temp_region.start = temp_start;
                temp_region.stop = temp_stop;

                overlap_regions.erase(me);

                list<OVERLAP>::iterator temp_itr = overlap_regions.erase(thee);

                me = overlap_regions.insert(temp_itr,temp_region);
                thee = temp_itr;
            }
            else{
                me++;
                thee++;
            }
        }
}

Answer 1

我相信您的me删除会使您的thee迭代器无效。

for(list<OVERLAP>::iterator thee = ++me; // Post-increment

这可以保证它们与for-initializer中的节点相同。你评论说后增量。不是后增量。因此，您可以这样做：

list<OVERLAP>::iterator temp_itr = overlap_regions.erase(me);

紧接着：

cout << "thee->ID:" << thee->id << endl;
cout << "thee->start:" << thee->start << endl;

...等。擦除“我”后，thee不再有效。访问它以进行读取是未定义的行为，但可能会起作用，因为在引用的数据指针处仍然存在某些。但它是一种非常少的未定义行为，最终通过erase()调用表现出来。

中止（核心转储）C ++ Cygwin

1 个答案: