Thanks, Ion! Regards, Alexander. ----- Original Message ----- From: "Ion Gaztañaga" To: "Boost User List" Sent: Saturday, December 02, 2006 3:03 AM Subject: Re: [Boost-users] interprocess::list and destructors of storedobjects

alexmark wrote:

...

Hi to all!

For the container type

boost::interprocess::list I

need the destructor of stored object T be called when erase() is called for a corresponding list item. By default the T destructor is not called, memory only is deallocated. What is the correct way to force boost::interprocess::list to invoke destructors for contained objects while list item or the container itself is deleted?

TYA.

Hi,

I've reviewed the code from the list.hpp CVS and I see that erase is written as:

iterator erase(const_iterator position) { NodePtr next_node = position.get_ptr()->m_next; NodePtr prev_node = position.get_ptr()->m_prev; NodePtr node = position.get_ptr(); prev_node->m_next = next_node; next_node->m_prev = prev_node; AllocHolder::destroy_node(node); --this->m_size; return iterator(next_node); }

And

AllocHolder::destroy_node(node);

is written as:

void destroy_node(NodePtr node) { if(!node_has_trivial_destructor){ self_t::destroy(node); } NodeAlloc::deallocate(node, 1); }

in theory, if the node has trivial destructor, the destructor shouldn't be called. but this "node_has_trivial_destructor" is:

enum { node_has_trivial_destructor = boost::has_trivial_destructor<NodePtr>::value | boost::has_trivial_destructor<T>::value };

which I think is wrong since it should be

enum { node_has_trivial_destructor = boost::has_trivial_destructor<NodePtr>::value && boost::has_trivial_destructor<T>::value };

that is, the node pointer should have trivial destructor AND the value should have trivial destructor. Otherwise, the destructor is wrongly ignored.

I've uploaded the change to CVS. You can change your list.hpp code to see if this works. The same bug is present in slist.hpp. Thanks for the bug report!

Regards,

Ion _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users