[Boost-bugs] [Boost C++ Libraries] #5965: indirect_iterator conflicts with forward declaration

Subject: [Boost-bugs] [Boost C++ Libraries] #5965: indirect_iterator conflicts with forward declaration
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-09-30 10:12:33

#5965: indirect_iterator conflicts with forward declaration
--------------------------------------------+-------------------------------
 Reporter:  Simon <simon.siemens@…>         |       Owner:  dave    
     Type:  Bugs                            |      Status:  new     
Milestone:  To Be Determined                |   Component:  iterator
  Version:  Boost 1.46.1                    |    Severity:  Problem 
 Keywords:                                  |  
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 indirect_iterator, or more precisely its base class indirect_base, checks
 whether it can dereference its argument twice.  This ends in an error, if
 the target type is incomplete (from a forward declaration). The error
 occurs even if the dereferencing is not used in the affected code unit.
 (It is concept checking.)

 /usr/include/boost/detail/is_incrementable.hpp:84: error: cannot increment
 a pointer to incomplete type ‘Derived’

 indirect_iterator handles pointers. Pointers and forward declaration
 should complete each other well. So indirect_iterator should never try to
 dereference if it is not forced by using code. Concept checking does not
 work here satisfactorily.

 I appended exemplary code which I compiled with GCC 4.4.3.

 Best regards,

 Simon

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5965>
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