Re: [hash2] Formal Review Begins

From: Ivan Matek (libbooze_at_[hidden])
Date: 2024-12-07 16:27:45

On Sat, Dec 7, 2024 at 5:18 PM Vinnie Falco via Boost <boost_at_[hidden]>
wrote:

> On Sat, Dec 7, 2024 at 7:27 AM Klemens Morgenstern via Boost <
> boost_at_[hidden]> wrote:
>
> > I wonder about the usefulness of pointers.
> >
>
> A use-case for pointers is:
>
>     std::unordered_map< T*, std::weak_ptr<T> >
>
> Where the T is constructed via std::make_shared. Note:
>
>
I think this case itself can easily be handled by people casting T* to
std::uintptr_t.
I think bigger issue is that users can not do this when pointer is nested
inside  a type.
E.g.
How can user hash
std::tuple<std::string, int*, int>
?
reinterpret cast to std::tuple<std::string, std::uintptr_t,  int>

Yikes + UB.

>
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