[boost] Re: Proposal: Efficient Pointers

From: Philippe A. Bouchard (philippeb_at_[hidden])
Date: 2002-07-17 12:20:35

"Ed Brey" <brey_at_[hidden]> wrote in message
news:ah3q5c$or7$1_at_main.gmane.org...
> "Philippe A. Bouchard" <philippeb_at_[hidden]> wrote in message
news:ah3b6t$nah$1_at_main.gmane.org...

[...]

> > Here is a draft version of what could remove copy constructors usages.
It
> > would require proper initialization from the user in this example.
Besides
> > the implicit reinterpret_cast<> in the constructor which shouldn't be
there
> > IMO, any thoughts?
>
> Looking at the code, I don't follow how it is supposed to work.  For
example, consider the code:
>
> squad_ptr<char> p(new char);
>
> In this case, squad_ptr puts its use count in memory immediately following
what was allocated for the character.  This amounts to a buffer overrun,
blowing past the block that the heap manager gave your program.

This was a too much optimized example and turned corrupted, but element_type
could also be constructed then retouched with new (element_type().m_buffer)
value_type(...) in 2 statements instead of one.

Here is another clean example using struct initiliazers which uses 1
statement and is more solid at construction time.

Philippe A. Bouchard

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`
end

begin 666 ice.cpp
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`
end