Re: [Boost-users] boost::exception_detail::error_info_base does not have virtual destructor

-----Original Message----- From: boost-users-bounces@lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Steven Watanabe Sent: March-17-11 12:37 PM To: boost-users@lists.boost.org Subject: Re: [Boost-users] boost::exception_detail::error_info_base does not have virtual destructor

AMDG

On 03/17/2011 08:50 AM, Jens Auer wrote:

...

I am compiling a project with a more strict warning set and got the following reports: Error 29 error C4265: 'boost::exception_detail::error_info_base' : class has virtual functions, but destructor is not virtual c:\work\svn\sandbox\externals\boost\include\boost-1_45\boost\exception\detai l\error_info_impl.hpp 36

Error 30 error C4265: 'boost::error_info' : class has virtual functions, but destructor is not virtual c:\work\svn\sandbox\externals\boost\include\boost-1_45\boost\exception\detai l\error_info_impl.hpp 69

IMHO these classes should have a virtual destructor as they are intended to be used as base classes.

No they shouldn't. A virtual destructor is only needed when deleting through a base class pointer. This is explicitly forbidden by making the destructor

Hi Stevem, protected. I must respectfully disagree. There are two ways to look at this 'should'. First, there is what is required or permitted by the standard. Second, there is what is useful in managing a software development project. When I am trying to help my juniors develop good programming habits, one of the things I want them to do is always provide a virtual destructor whenever they make one or more member functions virtual. That lets a team comprised of many more junior programmers than really really old guys like me avoid a lot of subtle bugs. And I don't see a significant down side to making a destructor virtual. Hence, when I am mentoring junior programmers, I routinely advise them to make destructors virtual whenever they need one of the other member functions to be virtual, whenever the issue arises. Are you aware of a significant downside to making destructors virtual as a matter of habit? Cheers Ted