Re: [boost] change to weak_ptr.hpp to compile under Builder C++ 5, etc

From: Thomas Witt (witt_at_[hidden])
Date: 2002-05-15 04:41:40

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On Tuesday 14 May 2002 20:02, Peter Dimov wrote:
> This will no longer be necessary with 1.28.0; we've removed operator* and
> operator-> from weak_ptr as unsafe. Now the only way to do something with a
> weak_ptr is to construct a shared_ptr first, via its constructor or
> make_shared.

Peter,

can you explain why make_shared adds safety. Currently I am unable to see why.
IIUC what happens is a NULL ptr is dereferenced with or without make_shared. 
On the first look it seems as if make_shared pretends to be safe but isn't. 
When make shared is used the object might be gone already.

Thanks

Thomas

- -- 
Dipl.-Ing. Thomas Witt
Institut fuer Verkehrswesen, Eisenbahnbau und -betrieb, Universitaet Hannover
voice: [phone] - 4273, fax: [phone]
http://www.ive.uni-hannover.de
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