Re: Why not reject the dynamic instantiation of a class with non-virtual destructor?

From:
"Nevin :-] Liber" <nevin@eviloverlord.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Thu, 3 Jul 2008 03:28:08 CST
Message-ID:
<nevin-AF5E08.11090702072008@chi.news.speakeasy.net>
In article <Xns9ACF5D7E82AE4AHTDHGYHVDGH463FF@195.197.54.116>,
  "Niklas B?ckman" <nikbackm@gmail.com> wrote:

Bart van Ingen Schenau <bart@ingen.ddns.info> wrote in
news:7279702.eRByVrWvqp@ingen.ddns.info:

 struct Base
 {
      ~Base(); // non-virtual
      virtual void foo() = 0;
 };

 void f(Base* p)
 {
      delete p;
 }

I would consider it a good QoI if the compiler gives a warning.


Will not C++0x fix this by automatically making the destructor virtual
as well if there are other virtual member functions in the class?


A warning for an abstract base class being deleted through a base
pointer is not the same thing as a silent change of magically adding a
virtual destructor to any class that has a virtual method. I sure don't
want the latter, as there are perfectly legal uses of this.

--
  Nevin ":-)" Liber <mailto:nevin@eviloverlord.com> 773 961-1620

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