deprecated delete and manual memory management

[Steven Schveighoffer]

On Tue, 26 Apr 2011 19:45:21 -0400, Daniel Gibson <metalcaedes at gmail.com>  
wrote:

> I just noticed something regarding clear():
>   struct Bar { ... }
>   Bar *b = new Bar();
> This compiles without any warning, but doesn't call the destructor:
>   clear(b);
> This compiles without any warning and actually does what you'd expect,
> i.e. calls destructor:
>   clear(*b);
>
> Is this behavior expected/wanted? If not: Is it a known bug? I couldn't
> find it in the bugtracker, but maybe I searched for the wrong keywords.

Let's start with class references.  Because class references cannot be  
separated from its reference, you have to finalize the class when  
finalizing the reference, because there's no way to say "clear what this  
reference refers to" vs. "clear this reference".  So you have to give a  
way to finalize a class instance.

With pointers, however, you can specify as you say, whether you want to  
clear the pointer or the struct itself.

Now, is it much useful to clear a pointer without clearing what it points  
to?  I'd say no, clearing a pointer is as easy as doing ptr = null.  So  
I'm thinking, it should be filed as a bug.

The obvious thing to decide is, what should be done on references to  
references?  If you clear a double pointer, should it go through both  
pointers?  Or a pointer to a class reference?

I'd say no, but you have to take extra steps to ensure it is this way.

-Steve