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https://issues.apache.org/jira/browse/STDCXX-612?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12556720#action_12556720
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Martin Sebor commented on STDCXX-612:
-------------------------------------

We need to be careful here. We can't change [revers.iter.opref] or any other 
function that deliberately relies on the return type of operator&() being 
[convertible to] pointer.

As for where things should be defined: _defs.h is for macro definitions only. 
There shouldn't be any other definitions (types, templates, or functions). As 
an aside, we should be using C++ casts in favor of the C-style ones.

Here's how I'd like to propose we proceed:

1) First, to simplify things, eliminate the _RWSTD_ARROW() macro. It's a 
workaround for a compiler limitation that none of our compilers suffers from 
anymore (check the generated config headers) and so this is a forward 
compatible change.

2) For standard container iterators define operator->() in terms of the pointer 
data member as opposed to in terms of operator&() and avoid having to deal with 
any conversion issues.

3) Leave reverse_iterator::operator->() unchanged (i.e., return &operator*()).

4) Change istream_iterator::operator->() to simply return &_C_val.

5) Change  __rw_debug_iter::operator->() to simply return _C_iter.

6) Discuss how to deal with the uninitialized_xxx() algorithms.

> many iterator types do not work with types that implement unary operator&
> -------------------------------------------------------------------------
>
>                 Key: STDCXX-612
>                 URL: https://issues.apache.org/jira/browse/STDCXX-612
>             Project: C++ Standard Library
>          Issue Type: Bug
>          Components: 24. Iterators
>    Affects Versions: 4.2.0
>            Reporter: Travis Vitek
>            Assignee: Farid Zaripov
>             Fix For: 4.2.1
>
>         Attachments: operator_arrow.patch
>
>
> Code that uses the macro _RWSTD_OPERATOR_ARROW will be affected by this 
> issue. Code that has '&*' is also very likely to be affected.
> #include <deque>
> #include <iterator>
> #include <list>
> #include <set>
> #include <vector>
> struct S
> {
>    void operator& () const {};
> };
> int main ()
> {
>    // this is just a compile test, it is not intended to run
>    std::reverse_iterator<S*>().operator->();
>    std::set<S>::iterator().operator->();
>    std::deque<S>::iterator().operator->();
>    std::list<S>::iterator().operator->();
>    return 0;
> }

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