Boost C++ Libraries: Ticket #2951: Unwanted implicit conversion from std::auto_ptr to boost:;shared_ptr

Peter Dimov — Thu, 16 Apr 2009 22:32:25 GMT

It should only allow implicit conversions from auto_ptr _rvalues_. Is this a problem? Do you have an example?

wmtan@… — Thu, 16 Apr 2009 23:01:56 GMT

It is definitely implicitly converting from an auto_ptr lvalue. We are using gcc3.4.5 (32 bit). We will be converting to gcc4.3 shortly, so I will check if the problem exists in gcc4.3.

I will get back to you with an example shortly.

wmtan@… — Fri, 17 Apr 2009 17:15:54 GMT

The following code compiles and runs. An auto_ptr lvalue is implicitly converted to a shared_ptr. This should not happen. This happens in gcc4.3 and gcc3.4, with no compiler options other than -I to include the boost header.

#include <memory>

#include <iostream>

#include "boost/shared_ptr.hpp"

struct X {

int i;

};

void f(boost::shared_ptr<X> sp) {

std::cout << sp->i << std::endl;

}

int main() {

std::auto_ptr<X> ap(new X); ap->i = 1; f(ap);

}

Peter Dimov — Fri, 17 Apr 2009 19:51:21 GMT

(In [52454]) Bring back "explicit" on the auto_ptr rvalue constructor. Refs #2951.

status changed; resolution set

Peter Dimov — Sat, 18 Apr 2009 22:43:01 GMT

status new → closed
resolution → fixed

Merged to release in [52472].