Re: compile error about auto_ptr

From:
Abhishek Padmanabh <abhishek.padmanabh@gmail.com>
Newsgroups:
microsoft.public.vc.language
Date:
Sat, 23 Feb 2008 06:26:51 -0800 (PST)
Message-ID:
<a4129f0b-7839-45ee-82a2-39b3a2e5816f@s8g2000prg.googlegroups.com>
On Feb 23, 7:11 pm, George <Geo...@discussions.microsoft.com> wrote:

I am confused to read what the compiler says. Could anyone explain what it=

means?

[Code]
#include <memory>
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main( )
{
        int i = 0;

        vector<auto_ptr<int>> vc;
        for (i = 0; i < 5; i ++) // 0 1 2 3 4
        {
                auto_ptr<int> pi (new int(i));
                vc.push_back (pi);
        }

        return 0;}

[/Code]

1>Compiling...
1>main.cpp
1>d:\program files\microsoft visual studio 9.0\vc\include\vector(1209) :
error C2558: class 'std::auto_ptr<_Ty>' : no copy constructor available or=

copy constructor is declared 'explicit'
1> with
1> [
1> _Ty=int
1> ]
1> d:\program files\microsoft visual studio
9.0\vc\include\vector(1158) : while compiling class template member functi=

on

'void
std::vector<_Ty>::_Insert_n(std::_Vector_const_iterator<_Ty,_Alloc>,unsign=

e=ADd

int,const _Ty &)'
1> with
1> [
1> _Ty=std::auto_ptr<int>,
1> _Alloc=std::allocator<std::auto_ptr<int>>
1> ]
1> d:\visual studio
2008\projects\test_autoptr1\test_autoptr1\main.cpp(11) : see reference to
class template instantiation 'std::vector<_Ty>' being compiled
1> with
1> [
1> _Ty=std::auto_ptr<int>
1> ]
1>d:\program files\microsoft visual studio 9.0\vc\include\vector(1233) :
error C2558: class 'std::auto_ptr<_Ty>' : no copy constructor available or=

copy constructor is declared 'explicit'
1> with
1> [
1> _Ty=int
1> ]


What are you confused about? The compiler error says that there is a
problem related to copy constructor of auto_ptr. See <memory> header
for your compiler (code for auto_ptr should be there) about how the
copy constructor is written and why it is a problem with your code.

Basically, you cannot use auto_ptr with standard containers. See this
for more details : http://www.gotw.ca/publications/using_auto_ptr_effectivel=
y.htm

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