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Date: Sun, 06 Feb 2011 23:01:00 -0000
Message-ID: <AANLkTi=geKqxML4bOgErAauweMXJSuXDJnPgerZStoc2@mail.gmail.com>
Subject: Re: C++ and garbage collection
From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: weigelt@metux.de, gcc-help@gcc.gnu.org
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On 5 February 2011 14:46, Enrico Weigelt wrote:
>> >
>> >> One viable approach is to modify the uses of pointers into shared_ptr
>> >> (from TR1 or boost) and then add the Boehm collector. =A0This process
>> >> takes work, because changing all pointers won't work and changing
>> >> none won't buy you anything.
>> >
>> > Guess this would take a lot of work and add more dependencies
>> > (than just the relatively small boehm-gc lib) ...
>>
>> GCC includes a tr1::shared_ptr so there's no extra dependency if you
>> are only planning to use g++, and std::shared_ptr is part of C++0x.
>
> How does that one actually work and what do I have to do to use it ?

#include <tr1/memory>

int main()
{
  using std::tr1::shared_ptr;

  shared_ptr<int> p(new int);
  *p =3D 5;
  assert( *p =3D=3D 5 );
  shared_ptr<int> p2(p);
  assert( p =3D=3D p2 );
  assert( p.use_count() =3D=3D 2 );
  p.reset();
  assert( p.use_count() =3D=3D 0 );
  assert( p2.use_count() =3D=3D 1 );
} // int deleted here

for more info read the docs for boost::shared_ptr (where the class
originated) or search the web, there is plenty of info on shared_ptr.