Re: BUG: compiler allows for creation of objects without destructor compiled

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From: David Olsen (qg4h9ykc5m_at_yahoo.com)
Date: 04/08/04 

Date: Thu, 08 Apr 2004 14:34:53 -0700

Maxim Yegorushkin wrote:
> David Olsen wrote:
>> According to the C++ standard (12.4/5) it is not an error to define a
>> class whose destructor cannot be defined (class "derived" in your
>> example). But it is an error to actually call the destructor of that
>> class.
>
> Does it mean that Comeau is wrong about producing the error message in
> Hendrik Schober's posting?

Yes and no. Comeau online (http://www.comeaucomputing.com/tryitout/)
seems to have it bugs in this area, which are different than VC's bugs.
  It correctly accepts:

class base { virtual ~base() { } };
class derived : public base { };

But it rejects the following, which should be valid code because the
destructor is never used:

class base { virtual ~base() { } };
class derived : public base { };
derived *f() { return new derived; }

And it accepts the following, which it should reject because the
destructor is used:

class base { virtual ~base() { } };
class derived : public base { };
void f(derived *x) { delete x; } 

-- 
David Olsen
qg4h9ykc5m@yahoo.com

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