[Boost-bugs] [Boost C++ Libraries] #7100: unorderd_set<shared_ptr<T> > > - insert does not increment count

Subject: [Boost-bugs] [Boost C++ Libraries] #7100: unorderd_set<shared_ptr<T> > > - insert does not increment count
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-07-07 03:59:01

#7100: unorderd_set<shared_ptr<T> > > - insert does not increment count
-----------------------------------------------+----------------------------
 Reporter:  Rich Eakin <reakinator@…>          |       Owner:  johnmaddock
     Type:  Bugs                               |      Status:  new        
Milestone:  To Be Determined                   |   Component:  TR1        
  Version:  Boost 1.51.0                       |    Severity:  Problem    
 Keywords:  unordered_set shared_ptr           |  
-----------------------------------------------+----------------------------
 It seems unordered_set::insert has stopped working for shared_ptr's
 between v 1.48 and now.  Consider the following example:

 {{{
 #include <iostream>

 #define USING_BOOST 1

 #if USING_LIBCPP

         #include <unordered_set>
         #include <memory>

 #elif USING_BOOST

         #include "boost/shared_ptr.hpp"
         #include "boost/unordered_set.hpp"

         using namespace boost;

 #endif

 using namespace std;

 int main()
 {
         unordered_set<shared_ptr<int> > mySet;
         shared_ptr<int> intSP( new int( 1 ) );

         cout << "use_count A: " << intSP.use_count() << endl;

         mySet.insert( intSP );

         cout << "use_count B: " << intSP.use_count() << endl;

     return 0;
 }

 }}}

 In boost-trunk (and release version 1.50), use_count after the insert is
 still 1.  In boost version 1.48, the use_count is incremented by the
 insert to 2.  This is also the case with libc++.

 Sorry, I don't know what the results are in 1.49.

 This was tested clang on Mac OS X:

 {{{
 $ clang --version
 Apple clang version 4.0 (tags/Apple/clang-421.10.48) (based on LLVM
 3.1svn)
 Target: x86_64-apple-darwin11.4.0
 Thread model: posix
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7100>
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