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From: Beman Dawes (bdawes_at_[hidden])
Date: 2002-09-09 13:46:50

At 11:13 AM 9/9/2002, Peter Dimov wrote:

>From: "Thomas Witt" <witt_at_[hidden]>
>> ptr != p should be a precondition violation.
>I agree (which is why shared_ptr's reset acts the way it does now),
>> I can't think of a good reason
>> why a scoped_ptr should be reset with a pointer that is already taken
>> by a scoped ptr.
>... the reason for the current behavior is std::auto_ptr compatibility.
>auto_ptr::reset is required to check for self-resets.
>> The current code fails if the dtor is called during a call to reset.
>> things like this can happen. The managed ptr will be deleted twice.
>If you can demonstrate this with an example, you may be able to convince
>Beman and Greg that scoped_ptr doesn't need to check for self-resets. :-)

The original code didn't check for self-reference IIRC. Someone sent in a
use case, but I can't remember what it was, and I can't remember if it
really applied to scoped_ptr.

Personally, I don't think I've ever used scoped_ptr::reset unless ptr==0.

Hum... That brings up a question. If myptr.get()==0, then shouldn't
myptr.reset() be harmless?



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