clear header node hooks upon intrusive container destruction

[Matei David <matei@…>]

In intrusive containers, the safe_link and auto_unlink hook types cause boost to reset the hooks to their default constructed state (usually NULL) upon removing an element from a container. That suggests a user could double check that nodes are indeed removed from all containers upon destruction, by checking that the hooks are set to NULL. Unfortunately, the check fails because, unlike all other regular nodes, the hooks of the container header nodes are not reset upon destruction of the container.

I will create a pull request which rectifies this in list, slist, and bstree. I will drop it on top of the develop branch, which has the recent fix to bug #9940.

I believe the change should have no negative impact.

[Matei David <matei@…>]

demonstrates the issue

[Matei David <matei@…>]

Pull request ​here.

[Ion Gaztañaga]

Fixed in commit SHA-1: fc6d3cca5fd7e122c4b608df3e659c1120552975

• Reverted wrong commit SHA-1: 62367b52e197b1dbca5ec8ba423a2ce3bfc89790 and removed include to recently deleted "detail/clear_on_destructor_base.hpp" file.