headers
Emil Dotchevski | 6 Sep 03:21

possible bug introduced in boost function

I have strong suspicions that the changes in boost::function made
today introduce a serious bug in the lifetime management of the
contained object. I don't have a simple test case to demonstrate it,
but a rather complicated use of boost::function which contains
shared_ptr in a boost::bind results in incorrect refcount which leads
to a crash.

Reverting to revision 48607 makes the shared_ptr refcount correct.

Emil Dotchevski
Reverge Studios, Inc.
http://www.revergestudios.com/reblog/index.php?n=ReCode
_______________________________________________
Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
Permalink | Reply |
headers
Emil Dotchevski | 6 Sep 04:06

Re: possible bug introduced in boost function

On Fri, Sep 5, 2008 at 6:22 PM, Emil Dotchevski <emil <at> revergestudios.com> wrote:
> I have strong suspicions that the changes in boost::function made
> today introduce a serious bug in the lifetime management of the
> contained object. I don't have a simple test case to demonstrate it,
> but a rather complicated use of boost::function which contains
> shared_ptr in a boost::bind results in incorrect refcount which leads
> to a crash.
>
> Reverting to revision 48607 makes the shared_ptr refcount correct.

Here's a simple test case, I tried it with msvc 9:

#include "boost/function.hpp"

int instances=0;
struct X
{
	X() { ++instances; }
	X(X const &) { ++instances; }
	~X() { --instances; }
	void operator()() { }
};
boost::function<void()> f() { return X(); }

int main( int argc, char const * argv[] )
{
	boost::function<void()> f2;
	f2=f();
	assert(instances==1);
}
(Continue reading)

Permalink | Reply |
headers
Niels Dekker - mail address until 2008-12-31 | 6 Sep 09:41
Favicon

Re: possible bug introduced in boost function

Emil Dotchevski wrote:
> I have strong suspicions that the changes in boost::function made
> today introduce a serious bug in the lifetime management of the
> contained object.
...
> Reverting to revision 48607 makes the shared_ptr refcount correct.

Thank you, Emil! Douglas has fixed the issue just a few hours ago:
  http://svn.boost.org/trac/boost/changeset/48627

See also:
  http://svn.boost.org/trac/boost/ticket/1910#comment:6

> Here's a simple test case, I tried it with msvc 9:
> 
> #include "boost/function.hpp"
> 
> int instances=0;
> struct X
> {
>         X() { ++instances; }
>         X(X const &) { ++instances; }
>         ~X() { --instances; }
>         void operator()() { }
> };
> boost::function<void()> f() { return X(); }
> 
> int main( int argc, char const * argv[] )
> {
>         boost::function<void()> f2;
(Continue reading)

Permalink | Reply |
headers
Douglas Gregor | 6 Sep 13:42
Favicon

Re: possible bug introduced in boost function

Emil Dotchevski wrote:
> I have strong suspicions that the changes in boost::function made
> today introduce a serious bug in the lifetime management of the
> contained object. I don't have a simple test case to demonstrate it,
> but a rather complicated use of boost::function which contains
> shared_ptr in a boost::bind results in incorrect refcount which leads
> to a crash.
>   
Thanks for pointing this out! I'm surprised I'd never put such a test 
into the Boost.Function test suite before. Anyway, the error has been 
fixed and I've added such a test.

  - Doug
_______________________________________________
Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
Permalink | Reply |
headers
Peter Dimov | 6 Sep 15:10

Re: possible bug introduced in boost function

Douglas Gregor:

> Thanks for pointing this out! I'm surprised I'd never put such a test 
> into the Boost.Function test suite before. Anyway, the error has been 
> fixed and I've added such a test.

Looking at

  http://svn.boost.org/trac/boost/changeset/48627

did you intend the large functor to be, well, large?
_______________________________________________
Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
Permalink | Reply |
headers
Douglas Gregor | 6 Sep 18:31
Favicon

Re: possible bug introduced in boost function

Peter Dimov wrote:
> Douglas Gregor:
>
>> Thanks for pointing this out! I'm surprised I'd never put such a test 
>> into the Boost.Function test suite before. Anyway, the error has been 
>> fixed and I've added such a test.
>
> Looking at
>
>  http://svn.boost.org/trac/boost/changeset/48627
>
> did you intend the large functor to be, well, large?
*Sigh*, yes. Thank you.

    - Doug
_______________________________________________
Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
Permalink | Reply |

Gmane